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Empirical “integrated disease management” in Ferrara during the Italian plague (1629–1631)
Abstract
Plague, a highly infective disease caused by Yersinia pestis (Proteobacteria: Enterobacteriales), ravaged Europe from 1347 over the course of more than 450 years. During the Italian Plague (1629–1631), the disease was rampaging in the entire Northern Italy down to Tuscany, but the city of Ferrara was relatively spared, in spite that the economic activities were maintained with highly affected cities, such as Milan, through the relevant salt commerce.
The aim of the study is to evaluate the hygiene rules that were effective in preventing the spread of the plague in Ferrara in 1630, by examining historical documents and reports. According to these documents, a kind of empirical “integrated disease management” was carried out, using remedies including compounds with bactericidal, anti-parasite and repellent activity, and by technical strategies including avoidance of possible plague carriers. The anti-plague remedies and technical strategies used in ancient Ferrara are critically analysed using a multidisciplinary approach (pharmaceutic, medical, epidemiologic and entomological) and compared to current prevention protocols.
... [9]. In Ferrara, according to documentation from the Diocesan Historical Archives, the mortality rate in that period was 20 deaths per week [10], absolutely regular for 32,000 inhabitants ( Figure 1). ...
... From a preliminary study of Ferrara's documents, it emerged that Ferrara, already in the 16th century, had already understood that the spread of the plague contagion could occur through domestic animals including cats, pigs, chickens, dogs that carry the plague from one house to another [10]. These animals can host vectors such as human flea P. irritans (which may colonize short haired mammals such as pigs), Ctenocephalides felis (the fleas of cats), C. canis (dogs) and Synopsyllus fonquerniei (chickens). ...
... In Ferrara city, a sort of "integrated empirical management of the disease" was carried out, using remedies that included compounds with antiparasitic and repellent activity (galenic), and technical strategies that included the prevention of possible plague carriers [10]. Sanitization of the house, exposure to fire and sun, ventilation, temperature and humidity, are in fact effective in vector control [17,18]. ...
The plague caused by the bacterium Yersinia pestis, provides one of the best historical examples of pandemic infection. It can therefore be considered the first "globalized" disease, thanks also to the crowds that favoured the rebalancing of infectious agents between Europe and the Middle East. In this paper we analyse all the official documents of the time, highlighting the most effective prevention measures implemented in the city of Ferrara during the Italian plague. Historical mortality data for the 1630 Italian plague in northern Italy are first analysed. In contrast to the high rates recorded throughout the area from Milan to Florence, the mortality rate in Ferrara remained normal over the period. From the city's documents it emerged that the authorities, from the 16th century onwards, had already understood that the spread of the contagion could also occur through domestic animals, although rats are never mentioned. The strength of Ferrara's response to the "plague emergency" stems from an efficient and emergency-ready health control system, financed and supported by the "permanent surveillance team of the city and the Pontifical Legation of Ferrara - Azienda Sanitaria Pubblica" even in times of great economic difficulty for the State. Among the various measures that the city of Ferrara adopted to deal with the plague the following should be mentioned: guards at the city gates, lazarettos, safety of doctors, self-isolation and treatment of every suspicious case as if it were a real case of plague, measures to support the poorer classes of the population, veterinary and hygiene standards for the city and for housing, management of Catholic religious functions and the precepts of the Legation of Ferrara, which was under papal control, closure of churches to avoid mass gatherings, and limitations of all kinds of social and economic relations within and outside the population. The broad regimen, laid down in the 16th century, contains extremely modern health rules which are very much in line with those recommended by the WHO and the health authorities of each individual state in the current COVID-19 pandemic, even starting with hand-washing. The fight against epidemics of the past, especially the history of the plague in the 17th century, anticipates very important and valid concepts, and represents a wake-up call for the recent epidemics of emerging pathogens.
... the study of the Black Death plague had a major impact on mainland europe as it killed at least one-third to two-thirds of the european population (Belich, 2016). in historical records, the Black Death plague is said to be a multiregional pandemic, this situation evidenced by the Black Death also occurring in most of asia and the Middle east (carmichael, 2006). as a result of the Black Death pandemic situation in the 1700s, there were several outbreaks in most parts of europe (cohn, 2008), namely the great plague of Milan (1629-1631) (Vicentini et al., 2020), the great plague of london (1665-1666) (Zell & Davies, 2022), the great plague of Vienna (1679) (laifle, 1937), and the great plague of Marseille (1720-1723) (Devaux, 2013). ...
This study examines the transmission of infectious diseases through historical studies, focusing on colonialization, slave trade, religion spread, and transcontinental and island trade. Emerging diseases like leprosy, Black Death, syphilis, malaria, Spanish flu, and COVID-19 have become significant contributors to global health crises. The study uses four stages: heuristics, critique, interpretation, and historiography. It focuses on migration, pandemics, and global health crises, using relevant literature. The findings suggest that many diseases have reached pandemic proportions due to their rapid dissemination and the influence of migration caused by historical factors such as ancient travel culture, colonialism, and modern times. The evolution of contemporary language also facilitates international mobility. The research examines the issue of disease distribution resulting from the long-standing global migration process, focusing on how migration has played a significant role in the occurrence of pandemics, outbreaks, and global health crises throughout history. The migration of Homo Sapiens from East Africa to regions outside Africa led to the development of language, culture, and disease transmission. The domestication of animals resulted in the emergence and transmission of disease mutations, leading to the worldwide dissemination of infectious diseases like leprosy, Black Death, syphilis, malaria, and COVID-19.
... The few cases, owing to strict laws and the rule of considering every suspected case as a plague and immediate isolation, enabled only the Lazaret of San Luca south of the city to be used. On the border of the Legation of Ferrara to the north and south Pontelagoscuro, Cento and Lugo (due to the relaxation of the measures) had numerous cases in the lazarets [7,1]. ...
... The curiosity of analysing the data, albeit limited to deaths, as there are no records of contagions, was to see if even in the case of the Spanish plague, although the city of Ferrara was not spared, it was less affected than other areas of the country. In our previous research, Ferrara was partially spared by the plague in the late 1500s and 1630s [32,33]. Today, it seems that COVID-19 during the first wave struck less violently in this city. ...
The “Spanish” flu has often been described as the “Greatest Medical Holocaust in History” and most vic- tims were young and healthy. In Italy, as elsewhere, this pandemic influenza struck in three successive and close waves with incredible speed in a very short time. The virus first arrived in a few Italian regions and gripped the country in an epidemic clamp. When the flu hit Ferrara, the health authorities began to claim that it was no more or less like the same disease that Ferrara had also experienced in the 19th century, al- though the population was not very willing to believe them. Moreover, the control measures were considered by all to be extremely mild, varying only the opening hours of cinemas and pharmacies and forbidding spit- ting on the ground; there was no disinfection of stores and streets and the dead were left at home for three days, unlike in larger cities. In 1918-19, Ferrara did much to contain the devastating effects of the war, es- pecially in terms of saving lives. The largest Red Cross unit in Italy, later called Ospedale Nuovo, was built. Moreover, since Ferrara was the first hospital evacua- tion zone, it was necessary to build other hospitals in the city’s schools in addition to the already existing ones, including the famous Ospedale Militare Neurologi- co di Villa Seminario, which was the first Italian neuro-
logical hospital of the Great War for veterans of the front line, intended for the specialised treatment of nervous disorders and psychosis caused by the war or by bombs.
We have extracted the cases of death from the Register of Deaths of the Municipality of Ferrara. During the pe- riod January 1918 - June 1919, in addition to the num- ber of deaths due to influenza, grippe or Spanish flu we also considered influenza-related complications affect- ing mortality and identified seven main groups of dis- eases by grouping them according to morbid forms and anatomical location. According to these criteria, 1,059 deaths were attributable to influenza or related causes during January-December 1918. This partly reflects the excess of deaths in the year 1918 of 1,279 over the aver- age for the years 1916-1919, and 1920. The largest num- ber of deaths was attributable to bronchopneumonia and pneumonia. However, an increase in mortality from other infectious diseases such as typhoid ileus, tuberculosis, malaria and smallpox was observed dur- ing the same period until January 2019, making up the shortfall in the total number of deaths recorded.
Keywords: Spanish flu, Ferrara, COVID-19, Pandemic, 1st World War, Prophylaxis, Register of death.
... Around 1629-1631 AD, the Italian Plague erupted, believed to originate from Yersinia Pestis bacteria in rats/fleas. It claimed up to 1 million lives [15][16]. ...
Juniper (Juniperus L., Cupressaceae Bartlett) trees are of high commercial value, as their essential oils are widely applied in the food and cosmetic industries due to their bioactivities. The genus Juniperus comprises eight species in Greece, and in the current work, we report the chemical analyses of their volatiles (GC-MS) obtained from the leaves and cones of all indigenous species found in the country, as well as their antimicrobial properties. The studied species were J. oxycedrus L., J. excelsa M. Bieb., J. foetidissima Willd., J. communis L., J. macrocarpa Sibth. & Sm., J. turbinata Guss., J. sabina L. and J. drupacea Labill., and a total of 164 constituents were identified. Monoterpenes, followed by sesquiterpenes, appeared as the dominant compounds in all investigated species. Most of the studied essential oils belonged to the α-pinene chemotype, with amounts of α-cedrol, sabinene, limonene and myrcene among the abundant metabolites, except for J. sabina, which belonged to the sabinene chemotype. Through antimicrobial tests, it was observed that the essential oils of most of the cones showed better activity compared with the respective leaves. The essential oils of the cones of J. foetidissima, J. communis and J. turbinata showed the strongest activity against the tested microorganisms. Additionally, in these three species, the content of thujone, which is a toxic metabolite found in essential oils of many Juniperus species, was considerably low. Taking into consideration the chemical profile, safety and antimicrobial activity, these three Greek Juniperus species seemed to provide the most promising essential oils for further exploitation in the food and cosmetics industries.
In early October 1347, 12 ships sailing from the Black Sea docked at Messina, Sicily. Most of the sailors were already deceased or critically ill at arrival. By January 1348, the Black Death had landed in Venice and Genova. A few weeks later, it appeared in Pisa, and from this foothold, it moved rapidly inland, east through Tuscany and south to Rome. By the winter of 1348, more than a third of Italy’s population had perished. While wealthy families were able to afford funerals, followed by only a handful of people. Ordinary people could not therefore, corposes of the deceased were left abandone in mass graves and other incinerated. Priests leading the procession, on arriving at the church, would find three or four additional biers in their wake. In contrast, the poor would leave their deceased family members in the streets to be carried off on plain boards, two or three at a time, to be buried in communal pits. Within 5 years AD, the black death (BD) disseminated all over the EU causing ~200 million deaths (30–50%) of the EU population (~1/3). Between 2010 and 2015, the WHO reported 3248 cases worldwide, including 584 deaths.KeywordsJustinian plagueJustinianic plague
Yersinia pestis
Managing crises in real time places a distinctive burden on public managers as they encounter a gap between cognition of risk and action taken to reduce that risk. The uncertainty implicit in risk that has not yet occurred impedes actions that would reduce the risk when it does occur. In practice, actions not taken in time accelerate losses when the hazard does occur. This recurring dilemma in public management is observed acutely in the context of the rapidly escalating threat of COVID-19. This article briefly compares response operations to COVID-19 in four countries—South Korea, Italy, United States, Mexico—and documents different operational responses and different consequences in the number of confirmed cases and deaths from COVID-19 among the countries. The differences in outcomes are linked to the concept of complex time, where the threat of COVID-19 is perceived with different degrees of experience, knowledge, and urgency among the countries. The article concludes that resistance to uncertainty and failure to act is reduced by creating a structured reasoning process for consistent inquiry into unknown conditions, and timely, credible reporting of the changing threat status. Findings are documented with data from Johns Hopkins University Coronavirus Research Center, Baltimore, MD, 2020–2021.
This brief survey article examines the strategies to cope with plague in early modern Italy, often hailed at the time and by historians as the country that provided the model for public health policies in other parts of Europe and even formed the basis for policies in subsequent centuries. The study is organised according to three mains themes that are familiar today, containment, mitigation, quarantine, which also lay at the heart of plague strategies in early modern Europe. The starting point will be to determine which measures contemporaries believed were particularly efficacious, through the lens of their own understanding of disease. Then, by juxtaposing recent historical and demographic studies, I examine the application and effectiveness of public health measures in a country that was comprised of a series of larger and smaller states. In the process, I seek to raise wider questions about whether it was human intervention or non‐human factors, in particular regional ecology, that determined the impact of plague in particular areas.
On 3 August 1900, bubonic plague (Yersinia pestis) broke out in Glasgow for the first time during the Third Pandemic. The local sanitary authorities rigorously tracked the spread of the disease and they found that nearly all of the 35 cases could be linked by contact with a previous case. Despite trapping hundreds of rats in the area, there was no evidence of a rat epizootic and the investigators speculated that the outbreak could be due to human-to-human transmission of bubonic plague. Here we use a likelihood-based method to reconstruct transmission trees for the outbreak. From the description of the outbreak and the reconstructed trees, we infer several epidemiological parameters. We found that the estimated mean serial interval was 7.4–9.2 days and the mean effective reproduction number dropped below 1 after implementation of control measures. We also found a high rate of secondary transmissions within households and observations of transmissions from individuals who were not terminally septicaemic. Our results provide important insights into the epidemiology of a bubonic plague outbreak during the Third Pandemic in Europe.
Aedes aegypti is the vector responsible for transmitting pathogens that cause various infectious diseases, such as dengue, Zika, yellow fever, and chikungunya, worrying health authorities in the tropics. Due to resistance of mosquitoes to synthetic insecticides, the search for more effective insecticidal agents becomes crucial. The aim of this study was to verify the larvicidal, adulticidal, and anticholinesterase activities of the essential oils of the Illicium verum (EOIV), Pimenta dioica (EOPD), and Myristica fragrans (EOMF) against Ae. aegypti. The essential oils (EOs) were obtained by hydrodistillation and analyzed by gas chromatography-mass spectrometry (GC-MS). The larvicidal and adulticidal activities of EOs were evaluated against third instar larvae and Ae. aegypti adult females, respectively, using the procedures of the World Health Organization (WHO) and the anticholinesterase activity of the EOs by the modified Ellman method. The following major components were identified: (E)-anethole (90.1%) for EOIV, methyl eugenol (55.0%) for EOPD, and sabinene (52.1%) for EOMF. All EOs exhibited larvicidal and adulticidal activity against Ae. aegypti. The highest larval mortality was observed in EOMF with LC50 = 28.2 μg mL⁻¹. Adult mortality was observed after 1 (knockdown) and 24 h exposure, with the highest potential established by the EOIV, KC50 = 7.3 μg mg female⁻¹ and LC50 = 10.3 μg mg female⁻¹. EOIV (IC50 = 4800 μg mL⁻¹), EOMF (IC50 = 4510 μg mL⁻¹), and EOPD (IC50 = 1320 μg mL⁻¹) inhibited AChE. EOMF (4130 μg mL⁻¹) and EOPD (IC50 = 3340 μg mL⁻¹) inhibited BChE whereas EOIV showed no inhibition. The EOs were toxic to larvae and adults of Ae. aegypti, as well as being less toxic to humans than the currently used insecticides, opening the possibility of elaboration of a natural, safe, and ecological bioinsecticide for vector control.
Researchers have published several articles using historical data sets on plague epidemics using impressive digital databases that contain thousands of recorded outbreaks across Europe over the past several centuries. Through the digitization of preexisting data sets, scholars have unprecedented access to the historical record of plague occurrences. However, although these databases offer new research opportunities, noncritical use and reproduction of preexisting data sets can also limit our understanding of how infectious diseases evolved. Many scholars have performed investigations using Jean-Noël Biraben’s data, which contains information on mentions of plague from various kinds of sources, many of which were not cited. When scholars fail to apply source criticism or do not reflect on the content of the data they use, the reliability of their results becomes highly questionable. Researchers using these databases going forward need to verify and restrict content spatially and temporally, and historians should be encouraged to compile the work.
Essential oils of aromatic and medicinal plants generally have a diverse range of activities because they possess several active constituents that work through several modes of action. The genus Artemisia includes the largest genus of family Asteraceae has several medicinal uses in human and plant diseases aliments. Extensive investigations on essential oil composition, antimicrobial, insecticidal and antioxidant studies have been conducted for various species of this genus. In this review, we have compiled data of recent literature (2012–2017) on essential oil composition, antimicrobial, insecticidal and antioxidant activities of different species of the genus Artemisia. Regarding the antimicrobial and insecticidal properties we have only described here efficacy of essential oils against plant pathogens and insect pests. The literature revealed that 1, 8-cineole, beta-pinene, thujone, artemisia ketone, camphor, caryophyllene, camphene and germacrene D are the major components in most of the essential oils of this plant species. Oils from different species of genus Artemisia exhibited strong antimicrobial activity against plant pathogens and insecticidal activity against insect pests. However, only few species have been explored for antioxidant activity.
Background
Fleas are important vectors of human and animal disease, and control measures for protection against their bites and flea-borne diseases are necessary.
Methods
The essential oils (EOs) of four native medicinal plants, Ziziphora tenuiore, Myrtus communis, Achillea wilhelmsii and Mentha piperita were isolated by hydrodistillation technique and analyzed by GC-MC. The repellent activity of EOs and synthetic compounds, DEET and permethrin, were assayed on human subjects against field collected fleas. The effective doses of 50% and 90% of EOs and synthetic compounds were estimated by probit analysis of dose and response regression line.
Results
Analysis of EOs revealed about 19 major components. All oils were found to be more repellent (ED50 range= 208–955μg cm⁻²) than DEET and permethrin (ED50 range= 27–182 × 10³μg cm⁻²). Thyme and myrtle oils showed high repellent activities and among the total detected terpenes, thymol (36.26%) and α-pinene (32.5%) were the major components of those oils respectively.
Conclusion
Low repellent potency of DEET and permethrin against fleas might be related to flea olfactory system and further molecular and electrophysiological studies are required to conceive new ideas for the discovery and development of the next generation of repellents. Based on high repellent activity of thyme and myrtle essential oils against Pulex irritans further studies should be staged to develop their appropriate effective formulations. Likewise, field trials should be carried out to evaluate the operational feasibility and dermal toxicity over a long period.
The poultry red mite, Dermanyssus gallinae, represents a key threat for the poultry industry worldwide. The control of D. gallinae is mainly achieved by continuous applications of acaricides. However, the fast-growing development of resistance, and the strict laws concerning chemicals admitted for treatments on food animals, highlighted the importance of alternative control tools. Here, we explored the potential of Artemisia sieberi essential oil against D. gallinae. In this study, the A. sieberi essential oil was analyzed using GC and GC-MS. The oil toxicity through contact and fumigant assays on adult mites was evaluated. The oil repellent activity was assessed on adult mites over different time intervals. Lastly, the residual toxicity of various doses of the oil was evaluated on D. gallinae until 14 days post treatment. GC and GC-MS showed that the oil was rich in α-thujone (31.5%), β-thujone (11.92%), camphor (12.3%), and 1,8-cineole (10.09%). Contact toxicity on adult mites showed 50% lethal concentration (LC50), LC90, and LC99 of 15.85, 26.63, and 35.42 μg/cm(3), respectively. In fumigant assays, the oil was toxic on D. gallinae, and mortality was significantly higher in open containers over closed ones, underlining the key role of highly volatile constituents. Repellent assays showed that after 24 h from the treatment, all doses of the A. sieberi essential oil led to significant repellent activity over the control, except for 2 μg/cm(3). After 48 h, A. sieberi essential oil tested at all doses led to significant repellent activity, if compared to the control. Residual toxicity assays showed that time exposure and concentration tested had a significant impact on mite mortality after 1, 2, 5, and 7 days from the treatment. Notably, mortality remained significantly higher over the control for 7 days after spraying with oil at 2%. Further field assays with selected molecules from the A. sieberi essential oil are ongoing, testing them in synergistic blends, as well as in microencapsulated formulations.
Citrus medica cv. ‘liscia’ and C. medica cv. ‘rugosa’ are two taxa of citron, belonging to the biodiversity of South Italy, in particular of Amalfi Coast, in the Campania region. The chemical composition of the essential oils (EOs) from fruit peels of both C. medica cultivars was studied by gas chromatography (GC) and gas chromatography-mass spectrometry (GC-MS) analyses. In all, 100 compounds were identified, 82 for C. medica cv. ‘liscia’, accounting for 91.4% of the total oil, and 88 for C. medica cv. ‘rugosa’, accounting for 92.0% of the total oil. Monoterpene hydrocarbons are the main constituents in both oils of C. medica cv. ‘liscia’ (79.1%) and C. medica cv. ‘rugosa’ (80.2%). In both oils, limonene (67.2%–62.8%) and camphene (8.5%–10.9%) are the main constituents. The antimicrobial activity of the EOs was assayed against some bacterial strains: Bacillus cereus (DSM 4313), Bacillus cereus (DSM 4384), Staphylococcus aureus (DSM 25693), Pseudomonas aeruginosa (ATCC 50071), and Escherichia coli (DSM 8579). Low concentrations of C. medica cv. ‘rugosa’ EO showed an inhibitory effect on P. aeruginosa and higher concentrations inhibited more B. cereus (4384) and E. coli than S. aureus. The cytotoxicity of the EO was evaluated against SH-SY5Y cell line. The influence of the EO on the expression of adenylate cyclase 1 (ADCY1) was also studied. The antimicrobial activity registered confirm their traditional uses as food preserving agents and led us to hypothesize the possible use of these oils as antimicrobials. The alterations in ADCY1 expression suggested a role for limonene in effects on the central nervous system.
Interest in essential oils with pesticidal activity against insects and pests is growing. In this study, essential oils from different parts (leaves, twigs and seeds) of Cinnamomum camphora L. Presl were investigated for their chemical composition, and insecticidal and repellent activities against the cotton aphid. The essential oils, obtained by hydrodistillation, were analyzed by GC×GC-TOFMS. A total of 96 components were identified in the essential oils and the main constituents found in the leaves and twigs were camphor, eucalyptol, linalool and 3,7-dimethyl-1,3,7-octatriene. The major components found in the seeds were eucalyptol (20.90%), methyleugenol (19.98%), linalool (14.66%) and camphor (5.5%). In the contact toxicity assay, the three essential oils of leaves, twigs and seeds exhibited a strong insecticidal activity against cotton aphids with LC50 values of 245.79, 274.99 and 146.78 mg/L (after 48 h of treatment), respectively. In the repellent assay, the highest repellent rate (89.86%) was found in the seed essential oil at the concentration of 20 μL/mL after 24 h of treatment. Linalool was found to be a significant contributor to the insecticidal and repellent activities. The results indicate that the essential oils of C. camphora might have the potential to be developed into a natural insecticide or repellent for controlling cotton aphids.
In Europe, there is a long history of administrative attempts, initially at the local and then later at the national level, to prevent, control and limit the violence of epidemics. In assessing the relative contribution of local and national management of disease, this article suggest that a distinction between the external and internal sources of epidemics ought to be drawn. When this is done, a role for the local measure, all too often ignored or disparaged, can be established. In particular, it is in the containment of endemic disease that the local response becomes crucial and finds its place in the defeat of epidemics.
Background
Plague, a zoonosis caused by Yersinia pestis, is found in Asia, the Americas but mainly in Africa, with the island of Madagascar reporting almost one third of human cases worldwide. In the highlands of Madagascar, plague is transmitted predominantly by two flea species which coexist on the island, but differ in their distribution. The endemic flea, Synopsyllus fonquerniei, dominates flea communities on rats caught outdoors, while the cosmopolitan flea, Xenopsylla cheopis, is found mostly on rats caught in houses. Additionally S. fonquerniei seems restricted to areas above 800 m. Climatic constraints on the development of the two main vectors of plague could explain the differences in their distribution and the seasonal changes in their abundance. Here we present the first study on effects of temperature and relative humidity on the immature stages of both vector species.
Methods
We examined the two species’ temperature and humidity requirements under experimental conditions at five different temperatures and two relative humidities. By employing multivariate and survival analysis we established the impact of temperature and relative humidity on development times and survival for both species. Using degree-day analysis we then predicted the average developmental threshold for larvae to reach pupation and for pupae to complete development under each treatment. This analysis was undertaken separately for the two relative humidities and for the two species.
Results
Development times and time to death differed significantly, with the endemic S. fonquerniei taking on average 1.79 times longer to complete development and having a shorter time to death than X. cheopis under adverse conditions with high temperature and low humidity. Temperature had a significant effect on the development times of flea larvae and pupae. While humidity did not affect the development times of either species, it did influence the time of death of S. fonquerniei. Using degree-day analysis we estimated an average developmental threshold of 9 °C for S. fonquerniei, and 12.5 °C for X. cheopis.
Conclusions
While many vector-borne diseases are limited to warm, low-lying regions, plague in Madagascar is unusual in being most prevalent in the cool, highland regions of the country. Our results point towards the possibility that this is because the endemic flea vector, S. fonquerniei, is better adapted to cool temperatures than the exotic flea vector, X. cheopis. Future warming caused by climate change might reduce the area suitable for S. fonquerniei and may thus reduce the incidence of plague in Madagascar.
The control of body lice is an important issue for human health and welfare because lice act as vectors of disease such as typhus, relapsing fever, and trench fever. Body lice exhibit avoidance behavior to some essential oils, including clove essential oil. Therefore, odorants containing clove essential oil components may potentially be useful in the development of repellents to body lice. However, such odorants that induce avoidance behavior in body lice have not yet been identified from clove essential oil. Here, we established an analysis method to evaluate the avoidance behavior of body lice to specific odorants. The behavioral analysis of the body lice in response to clove essential oil and its constituents revealed that eugenol, a major component of clove essential oil, has strong repellent effect on body lice, whereas the other components failed to induce obvious avoidance behavior. A comparison of the repellent effects of eugenol with those of other structurally related odorants revealed possible moieties that are important for the avoidance effects to body lice. The repellent effect of eugenol to body lice was enhanced by combining it with the other major component of clove essential oil, β-caryophyllene. We conclude that a synthetic blend of eugenol and β-caryophyllene is the most effective repellent to body lice. This finding will be valuable as the potential use of eugenol as body lice repellent.
Context: Insects can be the cause of major ecological problems; they can transmit microbes and parasites that affect humans, and damage food crops, trees, and homes. The total economic cost of insect-related damage and disease is immeasurable. In traditional Iranian medicine (TIM), several medicinal plants have been identified as insecticides or insect repellents, but many of them are still unknown. Therefore, the aim of this study was to review the insecticidal or insect repellent activity of certain medicinal plants described in TIM.
Evidence Acquisition: Information about medicinal plants proposed as insecticides and insect repellents in the TIM was collected from the TIM literature, and searched in modern medical databases to find studies that confirmed their efficacy.
Results: Modern investigations have supported the claims of the insecticidal activity of several plants, including Allium sativum, Artemisia absinthium, Citrullus colocynthis, Laurus nobilis, Mentha pulegium, Myrtus communis, Nerium oleander, Ocimum basilicum, and Origanum majorana. However, in the cases of plants like Iris florentina and Malva sylvestris, there is not enough evidence in modern medicine to prove their effectiveness with regard to their insecticidal and insect repellent activities.
Conclusions: This study confirmed the Iranian traditional medicine claims of the insecticidal and insect repellent activity of certain plants. Further pharmacological and clinical studies are recommended to evaluate the overall efficacy and possible mechanisms underlying these herbs.
Human plague remains a public health concern in Tanzania despite its quiescence in most foci for years, considering the recurrence nature of the disease. Despite the long-standing history of this problem, there have not been recent reviews of the current knowledge on plague in Tanzania. This work aimed at providing a current overview of plague in Tanzania in terms of its introduction, potential reservoirs, possible causes of plague persistence and repeated outbreaks in the country. Plague is believed to have been introduced to Tanzania from the Middle East through Uganda with the first authentication in 1886. Xenopsylla brasiliensis, X. cheopis, Dinopsyllus lypusus, and Pulex irritans are among potential vectors while Lophuromys spp, Praomys delectorum, Graphiurus murinus, Lemniscomys striatus, Mastomys natalensis, and Rattus rattus may be the potential reservoirs. Plague persistence and repeated outbreaks in Tanzania are likely to be attributable to a complexity of factors including cultural, socio-economical, environmental and biological. Minimizing or preventing people’s proximity to rodents is probably the most effective means of preventing plague outbreaks in humans in the future. In conclusion, much has been done on plague diagnosis in Tanzania. However, in order to achieve new insights into the features of plague epidemiology in the country, and to reorganize an effective control strategy, we recommend broader studies that will include the ecology of the pathogen, vectors and potential hosts, identifying the reservoirs, dynamics of infection and landscape ecology.
Herbs and spices have been used since ancient times, because of their antimicrobial properties increasing the safety and shelf life of food products by acting against foodborne pathogens and spoilage bacteria. Plants have historically been used in traditional medicine as sources of natural antimicrobial substances for the treatment of infectious disease. Therefore, much attention has been paid to medicinal plants as a source of alternative antimicrobial strategies. Moreover, due to the growing demand for preservative-free cosmetics, herbal extracts with antimicrobial activity have recently been used in the cosmetic industry to reduce the risk of allergies connected to the presence of methylparabens. Some species belonging to the genus Cinnamomum, commonly used as spices, contain many antibacterial compounds. This paper reviews the literature published over the last five years regarding the antibacterial effects of cinnamon. In addition, a brief summary of the history, traditional uses, phytochemical constituents, and clinical impact of cinnamon is provided.
Topography of the Po-Delta in Roman Times, roads and archaeological sites.
Introduction:
The aim of our study was to determine the antibacterial activity of cinnamon bark oil against Gram-positive and Gram-negative isolates belonging to Staphylococcus, Enterococcus, Enterobacter and Acinetobacter genera come from different clinical specimens.
Methods:
The microdilution method was used to determine the minimum inhibitory concentration--MIC for cinnamon bark oil. Susceptibility testing to antibiotics was carried out using disc-diffusion method.
Results:
Our investigations showed that the tested cinnamon bark oil was inhibiting activity against all isolates. The MIC for Gram-positive bacteria were between 01.25 and 1.5 μl/ml and for Gram-negative between 1.0 and 1.75 μl/ml. The tested bacteria come from Staphylococcus, Enterococcus, Enterobacter and Acinetobacter genera were susceptible to essential oil obtained from Cinnamomum zeylanicum Ness in low concentrations, despite the fact that the bacteria characterized the high resistance to recommended antibiotics. No correlation was found between the antibiotic resistance of the bacterial strains and their sensitivity to essential oil.
Conclusions:
The cinnamon bark oil due to the strong activity can be used as alternative antibacterial agents in cosmetics, toiletries and disinfectants applied in hospital environment.
Repellent activity of essential oils derived from 10 Thai native plants, belonging to three families were evaluated against female Aedes aegypti and Culex quinquefasciatus and to compare them with a commercial chemical repellents (DEET; N,N-diethyl-3-methylbenzamide 20 % w/w; Sketolene Shield®). Each test repellent was applied at 1, 5, and 10 % concentrations for testing by arm in cage method. The results showed significant differences in repellency among the repellents by mosquito species. The protection time of the essential oils against Ae. aegypti ranged from 3 to 30 min. According to the Culex mosquito, it showed the protection time ranged from 3 to 260 min. 10 % Boesenbergia rotunda essential oil provided the best efficiency, in which protection time was 4.3 h as equal as DEET. The essential oils which exhibited protection time more than 2 h were those of 10 % Zingiber zerumbet, Litsea petiolata, Curcuma zedoaria, and Zingiber cassumunar essential oils (3.1, 2.8, 2.6, and 2.3 h, respectively). The biting percentage ranged from 0.9 to 18.0 % and 0.8 to 3.6 % against Ae. aegypti and Cx. quinquefasciatus, respectively. The results revealed that the potential of essential oil extracted from B. rotunda, Z. zerumbet, L. petiolata, C. zedoaria, and Z. cassumunar had attributes of good repellent and deterred biting. We recommend the five essential oils for further study to develop as commercial repellents.
Effective and economical mycobactericidal disinfectants are needed to kill both Mycobacterium tuberculosis and non-M. tuberculosis mycobacteria. We found that acetic acid (vinegar) efficiently kills M. tuberculosis after 30 min of exposure to a 6% acetic acid solution. The activity is not due to pH alone, and propionic acid also appears to be bactericidal. M. bolletii and M. massiliense nontuberculous mycobacteria were more resistant, although a 30-min exposure to 10% acetic acid resulted in at least a 6-log10 reduction of viable bacteria. Acetic acid (vinegar) is an effective mycobactericidal disinfectant that should also be active against most other bacteria. These findings are consistent with and extend the results of studies performed in the early and mid-20th century on the disinfectant capacity of organic acids.
IMPORTANCE Mycobacteria are best known for causing tuberculosis and leprosy, but infections with nontuberculous mycobacteria are an increasing problem after surgical or cosmetic procedures or in the lungs of cystic fibrosis and immunosuppressed patients. Killing mycobacteria is important because Mycobacterium tuberculosis strains can be multidrug resistant and therefore potentially fatal biohazards, and environmental mycobacteria must be thoroughly eliminated from surgical implements and respiratory equipment. Currently used mycobactericidal disinfectants can be toxic, unstable, and expensive. We fortuitously found that acetic acid kills mycobacteria and then showed that it is an effective mycobactericidal agent, even against the very resistant, clinically important Mycobacterium abscessus complex. Vinegar has been used for thousands of years as a common disinfectant, and if it can kill mycobacteria, the most disinfectant-resistant bacteria, it may prove to be a broadly effective, economical biocide with potential usefulness in health care settings and laboratories, especially in resource-poor countries.
Plague, a zoonotic disease caused by the bacterium Yersinia pestis, has been responsible for at least 3 pandemics. During 1582-1583, a plague outbreak devastated the seaport of Alghero in Sardinia. By analyzing contemporary medical texts and local documentation, we uncovered the pivotal role played by the Protomedicus of Alghero, Quinto Tiberio Angelerio (1532-1617), in controlling the epidemic. Angelerio imposed rules and antiepidemic measures new to the 16th-century sanitary system of Sardinia. Those measures undoubtedly spared the surrounding districts from the spread of the contagion. Angelerio seems to have been an extremely successful public health officer in the history of plague epidemics in Sardinia.
This article compares the impact of plague across Europe during the seventeenth century. It shows that the disease affected
southern Europe much more severely than the north. Italy was by far the area worst struck. Using a new database, the article
introduces an epidemiological variable that has not been considered in the literature: territorial pervasiveness of the contagion.
This variable is much more relevant than local mortality rates in accounting for the different regional impact of plague.
Epidemics, and not economic hardship, generated a severe demographic crisis in Italy during the seventeenth century. Plague
caused a shock to the economy of the Italian peninsula that might have been key in starting its relative decline compared
with the emerging northern European countries.
In the new millennium, the centuries-old strategy of quarantine is becoming a powerful component of the public health response to emerging and reemerging infectious diseases. During the 2003 pandemic of severe acute respiratory syndrome, the use of quarantine, border controls, contact tracing, and surveillance proved effective in containing the global threat in just over 3 months. For centuries, these practices have been the cornerstone of organized responses to infectious disease outbreaks. However, the use of quarantine and other measures for controlling epidemic diseases has always been controversial because such strategies raise political, ethical, and socioeconomic issues and require a careful balance between public interest and individual rights. In a globalized world that is becoming ever more vulnerable to communicable diseases, a historical perspective can help clarify the use and implications of a still-valid public health strategy.
Myristica fragrans Houtt is mostly cultivated for spices in Penang Island, Malaysia. The ethyl acetate and ethanol extracts of flesh, mace and seed of Myristica fragrans was evaluated the bactericidal potential against three Gram-positive cariogenic bacteria (Streptococcus mutans ATCC 25175, Streptococcus mitis ATCC 6249, and Streptococcus salivarius ATCC 13419) and three Gram-negative periodontopathic bacteria (Aggregatibacter actinomycetemcomitans ATCC 29522, Porphyromonas gingivalis ATCC 33277, and Fusobacterium nucleatum ATCC 25586). Antibacterial activities of the extracts was determined by twofold serial microdilution, with minimum inhibitory concentrations (MIC) ranging from 1.25 to 640 mg/mL and 0.075 to 40 mg/mL. The minimum bactericidal concentration (MBC) was obtained by subculturing method. Among all extracts tested, ethyl acetate extract of flesh has the highest significant inhibitory effects against Gram-positive and Gram-negative bacteria with mean MIC value ranging from 0.625 to 1.25 ± 0.00 (SD) mg/mL; P = 0.017) and highest bactericidal effects at mean MBC value ranging from 0.625 mg/mL to 20 ± 0.00 (SD) mg/mL. While for seed and mace of Myristica fragrans, their ethanol extracts exhibited good antibacterial activity against both groups of test pathogens compared to its ethyl acetate extracts. All of the extracts of Myristica fragrans did not show any antibacterial activities against Fusobacterium nucleatum ATCC 25586. Thus, our study showed the potential effect of ethyl acetate and ethanol extracts from flesh, seed and mace of Myristica fragrans to be new natural agent that can be incorporated in oral care products.
Carlinae radix is an herbal drug, commonly used by the locals in southeastern Serbia for the treatment of respiratory and urogenital diseases and, externally, for various skin conditions. There still seems to be no detailed studies correlating the chemical composition of this drug and its ethnopharmacological uses.
Chemical composition, antimicrobial activity and mode of action of C. radix essential oil, isolated from commercial samples (confirmation of whose true biological identity was also the aim of this work) were analyzed. Antimicrobial potential of decoctions (extracts prepared by boiling plant material in a given solvent), used in ethnomedicine preferentially to the pure essential oil, was also investigated.
The essential oil obtained by hydrodistillation was screened for antimicrobial activity by disc diffusion and broth microdilution methods. Effects of the oil on the growth of Staphylococcus aureus cells were investigated using turbidimetric measurements and visualized using scanning electron microscopy. Analyses of the chemical composition of the oils were done using gas chromatography and gas chromatography/mass spectrometry.
Both the essential oil and the decocts exhibited a very high antimicrobial activity against all tested strains, with S. aureus as the most sensitive one [e.g., for the oil sample the values for minimal inhibitory concentration (MIC) and minimal bactericidal concentration (MBC) were 0.02, 0.04 µL/mL, respectively]. Growth curves of S. aureus demonstrated a significant decrease in turbidity (for the MIC concentration this amounted to ca. 70%) showing a concentration-dependent lysis of the cells, confirmed by scanning electron microscopy. Chemical composition, anatomical and morphological features of the sample pointed to Carlina acanthifolia L. (Asteraceae) instead of Carlina acaulis L. (Asteraceae).
The results showed significant antimicrobial effect of the essential oil and the decoctions and support the use of this plant in ethnomedicine for the treatment of various human infections, especially those caused by S. aureus. Adulteration of the drug would not cause significant differences in its biological activity, since chemical composition of the sample showed high similarity with those containing C. acaulis roots.
Alcoholic extracts of Goat's Rue (Galega officinalis L.; Papilionaceae) were tested on Gram +ve and Gram −ve bacteria as the plant was claimed to hasten skin healing after surgery. Ethanolic (60%) extract exhibited significant inhibition on growth of both Gram +ve and Gram −ve bacteria.
Juniperus communis leaf oil, J. chinensis wood oil, and Cupressus funebris wood oil (Cupressaceae) from China were analyzed by gas chromatography and gas chromatography-mass spectrometry. We identified 104 compounds, representing 66.8-95.5% of the oils. The major components were: α-pinene (27.0%), α-terpinene (14.0%), and linalool (10.9%) for J. communis; cuparene (11.3%) and δ-cadinene (7.8%) for J. chinensis; and α-cedrene (16.9%), cedrol (7.6%), and β-cedrene (5.7%) for C. funebris. The essential oils of C. funebris, J. chinensis, and J. communis were evaluated for repellency against adult yellow fever mosquitoes, Aedes aegypti (L.), host-seeking nymphs of the lone star tick, Amblyomma americanum (L.), and the blacklegged tick, Ixodes scapularis Say, and for toxicity against Ae. aegypti larvae and adults, all in laboratory bioassays. All the oils were repellent to both species of ticks. The EC(95) values of C. funebris, J. communis, and J. chinensis against A. americanum were 0.426, 0.508, and 0.917 mg oil/cm(2) filter paper, respectively, compared to 0.683 mg deet/cm(2) filter paper. All I. scapularis nymphs were repelled by 0.103 mg oil/cm(2) filter paper of C. funebris oil. At 4 h after application, 0.827 mg oil/cm(2) filter paper, C. funebris and J. chinensis oils repelled ≥80% of A. americanum nymphs. The oils of C. funebris and J. chinensis did not prevent female Ae. aegypti from biting at the highest dosage tested (1.500 mg/cm(2) ). However, the oil of J. communis had a Minimum Effective Dosage (estimate of ED(99) ) for repellency of 0.029 ± 0.018 mg/cm(2) ; this oil was nearly as potent as deet. The oil of J. chinensis showed a mild ability to kill Ae. aegypti larvae, at 80 and 100% at 125 and 250 ppm, respectively.
The essential oils from rhizomes of Alpinia conchigera Griff, Zingiber zerumbet Smitt, Curcuma zedoaria (Berg.) Roscoe; their major compounds (camphene, camphor, 1,8-cineole, alpha-humulene, isoborneol, alpha-pinene, beta-pinene and terpinen-4-ol); and synthetic essential oils comprised of mixtures of major pure compounds in the same ratios as the extracted essential oils were tested for contact, feeding reduction, and repellency against Sitophilus zeamais Motschulsky and Tribolium castaneum (Herbst) adults. Via topical applications, the three extracted oils had similar toxicity against S. zeamais (LD50 fiducial limits: 18-24 microg oil/mg insect). T. castaneum had similar sensitivity to all three oils (35-58 microg/mg), and it was less sensitive than S. zeamais. The LD50 values of synthetic A. conchigera and synthetic Z. zerumbet oils were similar to those of their corresponding extracted essential oils. The synthetic C. zedoaria oils showed lower contact toxicity than the extracted C. zedoaria oils to both insects. Sitophilus zeamais and T. castaneum were sensitive to terpinen-4-ol and isoborneol in contact toxicity tests. In antifeedant tests, the three extracted oils were able to decrease the consumption of flour disks, especially Z. zerumbet oils, whereas both insect species could feed on the flour disks treated with three synthetic essential oils. Only terpinen-4-ol deterred feeding in both insects. In repellency tests, A. conchigera oils at highest concentration repelled S. zeamais and T. castaneum. None of the synthetic essential oils repelled S. zeamais (315 microl/cm2) and T. castaneum (31 microl/cm2) Only terpinen-4-ol showed repellent activity against both insects.
The increased incidence of Multidrug-Resistant Mycobacterium tuberculosis (MDR-MT) requires the search for alternative antimycobacterial drugs. The main aim of this study was to evaluate the dichloromethane extract from Aristolochia brevipes (Rhizoma) and the compounds isolated from this extract against several mycobacterial strains, sensitive, resistant (monoresistant), and clinical isolates (multidrug-resistant), using the alamarBlue™ microassay. The extract was fractionated by column chromatography, yielding the following eight major compounds: (1) 6α-7-dehydro-N-formylnornantenine; (2) E/Z-N-formylnornantenine; (3) 7,9-dimethoxytariacuripyrone; (4) 9-methoxy-tariacuripyrone; (5) aristololactam I; (6) β-sitosterol; (7) stigmasterol; and (8) 3-hydroxy-α-terpineol. The structures of these compounds were elucidated by ¹H- and ¹³C- (1D and 2D) Nuclear Magnetic Resonance (NMR) spectroscopy. This study demonstrates that the dichloromethane extract (rhizome) of A. brevipes possesses strong in vitro antimycobacterial activity against Mycobacterium tuberculosis H37Rv (Minimum Inhibitory Concentration value [MIC], 12.5 µg/mL). The most active compound against all mycobacterial strains tested was the compound aristolactam I (5), with MIC values ranging between 12.5 and 25 µg/mL. To our knowledge, this the first report of antimycobacterial activity in this plant.
Methanolic extracts of flowers and leaves of Gentiana lutea L., together with the isolated compounds mangiferin, isogentisin and gentiopicrin, were used to investigate the antimicrobial activity of the plant. A variety of Gram-positive and Gram-negative bacteria as well as the yeast Candida albicans has been included in this study. Both extracts and isolated compounds showed antimicrobial activity with MIC values ranging from 0.12-0.31 mg/ml. Our study indicated that the synergistic activity of the pure compounds may be responsible for the good antimicrobial effect of the extracts. Quantification of the secondary metabolites was performed using HPLC.
The bacteriostatic and bactericidal actions of vinegar on food-borne pathogenic bacteria including enterohemorrhagic E. coli (EHEC) O157:H7 were examined. The growth of all strains evaluated was inhibited with a 0.1% concentration of acetic acid in the vinegar. This inhibition was generally increased in the presence of sodium chloride or glucose. There was almost no difference in sensitivity to the bacteriostatic action of vinegar among the strains of pathogenic E. coli. Vinegar had a bactericidal effect on food-borne pathogenic bacteria including EHEC O157:H7. This action against EHEC O157:H7 was synergically enhanced by sodium chloride but was attenuated with glucose. For EHEC strains (O157:H7, O26:H11, O111:HNM) the difference in the inactivation rate due to vinegar among strains used was small, although an enteropathogenic E. coli (EPEC) O111:K58:H- strain was more sensitive, being more quickly killed compared with EHEC strains. The inactivation rate due to vinegar was constant irrespective of inoculum size. However, it differed greatly depending on growth phase of the cells, where logarithmic growth phase cells were more sensitive and easily killed than stationary phase cells. The bactericidal activity of vinegar increased with the temperature. Various conditions for bactericidal effects on EHEC O157:H7 were examined by the multiparametric analysis of five factors: acetic acid concentration in the vinegar, sodium chloride concentration, temperature, incubation time, and viable cell number. The combined use of vinegar and sodium chloride, with use of an appropriate treatment temperature, was found to be markedly effective for the prevention of bacterial food poisoning.
Domestic fleas were collected in 12 villages in the western Usambara Mountains in Tanzania. Of these, 7 are considered villages with high plague frequency, where human plague was recorded during at least 6 of the 17 plague seasons between 1986 and 2004. In the remaining 5 villages with low plague frequency, plague was either rare or unrecorded. Pulex irritans, known as the human flea, was the predominant flea species (72.4%) in houses. The density of P. irritans, but not of other domestic fleas, was significantly higher in villages with a higher plague frequency or incidence. Moreover, the P. irritans index was strongly positively correlated with plague frequency and with the logarithmically transformed plague incidence. These observations suggest that in Lushoto District human fleas may play a role in plague epidemiology. These findings are of immediate public health relevance because they provide an indicator that can be surveyed to assess the risk for plague.
This article aims to analyse the effects of plague on the long‐term development of Italian cities, with particular attention to the 1629–30 epidemic. By using a new dataset on plague mortality rates in 56 cities covering the period c. 1575–1700, an economic geography model verifying the existence of multiple equilibria is estimated. It is found that cities severely affected by the 1629–30 plague were displaced to a lower growth path. It is also found that plague caused long‐lasting damage to the size of Italian urban populations and to urbanization rates. These findings support the hypothesis that seventeenth‐century plagues played a fundamental role in triggering the process of relative decline of the Italian economies.
Mung bean sprouts were implicated in several foodborne outbreaks worldwide in recent years. The objectives of this study were to (i) assess the efficacy of individual (mild heat) and combined treatments (mild heat followed by acetic acid or/and hydrogen peroxide) for the inactivation of enteric bacterial pathogens on mung bean intended for sprout production and (ii) determine the impact of the treatments and storage conditions on germination. Mung bean was co-inoculated with Escherichia coli O157:H7, Salmonella enterica and Listeria monocytogenes to achieve initial populations of approximately 5–6 log CFU of each species/g bean. The inoculated bean was then subjected to eight different treatments immediately after inoculation and after four weeks of storage at 22 °C. Selective media were used to estimate residual populations of each pathogen after treatment and subsequent to germination. The results showed that all combined treatments achieved a minimum 3-log CFU/g reduction in E. coli O157:H7, S. enterica and L. monocytogenes on freshly inoculated bean. The combined treatment with hot water followed by exposure to H2O2 and acetic acid resulted in a > 3-log reduction on mung bean stored for four weeks. The bactericidal effect of the combined treatments was significantly (P < 0.05) impacted by the duration of treatment and bean storage time. These data suggest that the combined use of mild heat, acetic acid and H2O2 may serve as a choice for organic sprouts industry in the disinfection of mung bean.
Fleas are a monophyletic group that has evolutionary ties with the mecopteroid insect orders—namely, Mecoptera and Diptera. They are morphologically unique ectoparasites. There are approximately 2500 species and subspecies of fleas that are currently placed in 15 families and 220 genera. Flea classification is based almost exclusively on the chitinous morphology of cleared adult specimens. Adult fleas are small (1─8 mm), wingless, almost invariably, bilaterally compressed, and heavily chitinized. Fleas are holometabolous insects, with an egg, larval (typically consisting of three instars), and pupal stage. Fleas have evolved a plethora of specialized behaviors and ecologies to locate and exploit their hosts. Mating behavior in most fleas follows a distinct sequence of events. There are many fleas that are of medical-veterinary importance such as human flea, oriental rat flea, cat flea, European rabbit flea, and many more. Many species are annoying biters that can cause considerable discomfort, sometimes leading to secondary infections of bite wounds. The bites of some species can cause dermatitis or allergic reactions. Various methodologies are used to control fleas or to protect humans and other animals from flea bites that are frequent during vacuuming in homes, steam cleaning of carpets, treatment of flea-infested premises with various insecticides, personal protectants, and the use of ultrasonic repellent devices.
Crocus sativus L. is known in herbal medicine for the various pharmacological effects of its components, but no data are found in literature about its biological properties toward Helicobacter pylori, Plasmodium spp. and Leishmania spp. In this work, the potential anti-bacterial and anti-parasitic effects of crocin and safranal, two important bioactive components in C. sativus, were explored, and also some semi-synthetic derivatives of safranal were tested in order to establish which modifications in the chemical structure could improve the biological activity. According to our promising results, we virtually screened our compounds by means of molecular modeling studies against the main H. pylori enzymes in order to unravel their putative mechanism of action.
In this paper, the chemical composition and biological activity of the essential oil of Artemisia absinthium was studied. The aim of this study was to investigate the potential of ethnopharmacological uses of this plant species in the treatment of gastrointestinal diseases and wounds, and as an insect repellent. The aerial part of the plant was hydrodistilled, and the chemical composition of the essential oil was analyzed by gas chromatography and gas chromatography/mass spectrometry. Forty-seven compounds, corresponding to 94.65 % of the total oil, were identified, with the main constituents being sabinene (24.49 %), sabinyl acetate (13.64 %), and α-phellandrene (10.29 %). The oil yield was 0.23 % (v/w). The antimicrobial activity of the oil was investigated against ten bacterial isolates (from patients wounds and stools) and seven American Type Culture Collection strains using a microwell dilution assay. The minimal inhibitory/bactericidal concentration of the oil ranged from < 0.08 to 2.43 mg/mL and from 0.08 to 38.80 mg/mL, respectively. The antioxidant activity of the essential oil was evaluated using 2,2-diphenyl-1-picrylhydrazil and 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) radical-scavenging methods and assessed as significant. Skin irritation potential and acute toxicity of the oil were also investigated. Results of the skin irritant reaction showed that none of the 30 volunteers developed a positive skin irritant reaction to undiluted A. absinthium essential oil. Acute oral exposure to the essential oil did not cause mortality in the treated mice, but it did cause neurological, muscle, and gastrointestinal problems. A subchronic toxicity test on Drosophila melanogaster showed that the essential oil of A. absinthium is toxic for developing insect larvae. Starting with the concentration of 0.38 % of essential oil in medium, significant mortality of larvae exposed to the oil was noted when compared to the control. Probit analysis revealed that the LC50 value of A. absinthium essential oil for D. melanogaster larvae after 15 days of exposure was 6.31 % (49 mg/mL). The essential oil also affected the development of D. melanogaster larvae and significantly delayed achievement of the pupa stadium.
The need for new antimicrobial agents is becoming one of the most urgent requirements in modern medicine. The venoms of many different species are rich sources of biologically active components and various therapeutic agents have been characterized successfully including antimicrobial peptides (AMPs). Due to their potent activity, low resistance rates and unique mode of action, AMPs have recently received much attention. This review focuses on AMPs from the venoms of scorpions and examines all classes of AMPs found to date. It gives details of their biological activities with reference to peptide structure. The review examines the mechanism of action of AMPs and with this information, suggests possible mechanisms of action of less well characterised peptides. Finally, the review examines current and future trends of scorpion AMP research, by discussing recent successes obtained through proteomic and transcriptomic approaches.
The search for more eco-friendly acaricides has prompted testing of medicinal plants from botanical sources.
To evaluate the eradication of house dust mites (HDM), Dermatophagoides pteronyssinus, by direct contact using the essential clove oil (Eugenia caryophyllus).
A pilot study was initiated to determine the killing power of clove oil. Synthetic fibers were immersed in 2% clove oil for 30 min, dried in a hot air oven at 60°C for 2 hrs after which 0.5 gm of HDMs were exposed to these coated fibers placed in the Siriraj Chamber (SC). Two additional long-term methods were employed. Ten mites were placed in the SC and 10 μl of clove oil was pipetted or sprayed onto them. These latter two procedures were each carried out for 3 consecutive days at 0, 1, 3 and 6 months. The solutions antimicrobial and antifungal properties were evaluated by exposing common bacteria and fungi to sterile filter disks impregnated with the mixture, and after overnight incubation, the disc diffusion method on nutrient agar was used. Ethyl alcohol served as the placebo. 99% and 81%, respectively, while the placebo mortality was <5%. The zone of inhibition indicated significant clearance for all the bacteria and fungi indicating greater biocidal activity when compared to the controls.
SEMs revealed dead mites on the fibers. The effectiveness of pipetting and spraying was 99% and 81%, respectively, while the placebo mortality was <5%. The zone of inhibition indicated significant clearance for all the bacteria and fungi indicating greater biocidal activity when compared to the controls.
Clove oil is a promising agent for killing dust mites with a potential use in dust-mite laden mattresses. Spraying diminishes in efficiency after 3 months.
Unlabelled:
Insect-resistant films containing a microencapsulated insect-repelling agent were developed to protect food products from the Indian meal moth (Plodia interpunctella). Cinnamon oil (CO), an insect repelling agent, was encapsulated with gum arabic, whey protein isolate (WPI)/maltodextrin (MD), or poly(vinyl alcohol) (PVA). A low-density polyethylene (LDPE) film was coated with an ink or a polypropylene (PP) solution that incorporated the microcapsules. The encapsulation efficiency values obtained with gum arabic, WPI/MD, and PVA were 90.4%, 94.6%, and 80.7%, respectively. The films containing a microcapsule emulsion of PVA and CO or incorporating a microcapsule powder of WPI/MD and CO were the most effective (P < 0.05) at repelling moth larvae. The release rate of cinnamaldehyde, an active repellent of cinnamaldehyde, in the PP was 23 times lower when cinnamaldehyde was microencapsulated. Coating with the microcapsules did not alter the tensile properties of the films. The invasion of larvae into cookies was prevented by the insect-repellent films, demonstrating potential for the films in insect-resistant packaging for food products.
Practical application:
The insect-repelling effect of cinnamon oil incorporated into LDPE films was more effective with microencapsulation. The system developed in this research with LDPE film may also be extended to other food-packaging films where the same coating platform can be used. This platform is interchangeable and easy to use for the delivery of insect-repelling agents. The films can protect a wide variety of food products from invasion by the Indian meal moth.
Unlabelled:
Sandalwood oil has been found in numerous therapeutic applications in traditional medicines such as Chinese traditional medicine and Ayurveda. However, there are no comparative accounts available in the literature that focused on in vitro and in vivo tree sample-derived extracts. Combined dichloromethane and methanol extracts were obtained from in vitro samples, that is, callus, somatic embryo and seedlings, and in vivo from leaves of non-oil-yielding young and oil-yielding matured trees. Phytochemical evaluation of the extracts reveals that the tree is rich in terpenoids, saponin, phenolics and tannins. The antibacterial properties of the five extracts were compared with sandalwood oil by screening against nine Gram-negative and five Gram-positive bacterial strains by disc diffusion, agar spot and TLC bioautography methods. Minimum inhibitory concentration (MIC) for sandalwood oil was determined to be in the range of 0·078-5 μg ml(-1) for most of the test micro-organisms screened. Bioautography results indicated the presence of potential antimicrobial constituents in somatic embryo extracts and sandalwood oil. Among the extracts screened, the somatic embryo extracts showed the strongest antibacterial activity comparable only with sandalwood oil and matured tree leaves' extract. The findings presented here also suggest that apart from sandalwood oil, other parts of this tree across developmental stages are also enriched with antibacterial principles.
Significance and impact of study:
This study constitutes the first systematic investigation on phytochemical composition and antimicrobial efficacy of sandalwood tree across in vitro and in vivo developmental stages screened against thirteen bacterial strains by four methods. Using a battery of antimicrobial assay techniques, it is possible to follow the differential bioactive metabolic richness of plant parts, to decipher, for example comparable efficacy of somatic embryo extracts and sandalwood oil.
In this study, the effects of Benzoinum and Styrax on Escherichia coli (E. coli) growth were investigated by microcalorimetry. Using a TAM Air Isothermal Calorimeter, ampoule method, the power-time curves of E. coli growth at 37°C affected by Benzoinum and Styrax were measured. By analysing some quantitative thermokinetic parameters, such as growth rate constants k, the maximum heat-out power Pm, the time of the maximum heat-out power tm, the total heat production Qt and inhibitory ratio I, one could find that low concentrations (0-3.9 mg mL(-1)) of Benzoinum and Styrax had stimulation effects on E. coli growth, and high concentrations (7.8-125.0 mg mL(-1)) of these two drugs would inhibit the growth of the bacteria. The antibacterial effects of Benzoinum and Styrax can also be expressed as half inhibitory concentration IC50. The IC50 values for Benzoinum and Styrax are 78.5 and 88.0 mg mL(-1), respectively, which suggests that the antibacterial effect of Benzoinum on E. coli was much stronger than that of Styrax. This study provides a useful method to investigate the effects of herbal medicines on microbes. It also supplies some references for the application of Benzoinum and Styrax in clinical treatment.
Phospholipase A(2) (PLA(2)), a common toxic component of snake venom, has been implicated in various pharmacological effects. In this study, a basic myotoxic PLA(2), named EcTx-I was isolated from Echis carinatus snake venom by using gel filtration on Superdex G-75, and reverse phase HPLC on C18 and C8 Sepharose columns. PLA(2), EcTx-I was 13,861.72 molecular weight as estimated by MALDI-TOF (15 kD by SDS-PAGE), and consisted of 121 amino acid residues cross-linked by seven disulfide bonds. The N-terminal sequences revealed significant homology with basic myotoxic PLA(2)s from other snake venoms. The purified PLA(2) EcTx-I was evaluated (250 μg/ml) for bactericidal activity of a wide variety of human pathogens against Burkholderia pseudomallei (KHW&TES), Enterobacter aerogenes, Escherichia coli, Proteus vulgaris, Proteus mirabilis, Pseudomonas aeruginosa and Staphylococcus aureus. EcTx-I showed strong antibacterial activity against B. pseudomallei (KHW) and E. aerogenes among the tested bacteria. Other Gram-negative and Gram-positive bacteria showed only a moderate effect. However, the Gram-positive bacterium E. aerogenes failed to show any effect on EcTx-I protein at tested doses. The most significant bacteriostatic and bactericidal effect of EcTx-I was observed at MICs of >15 μg/ml against (B. pseudomallei, KHW) and MICs >30 μg/ml against E. aerogenes. Mechanisms of bactericidal and membrane damaging effects were proved by ultra-structural analysis. EcTx-I was able to induce cytotoxicity on THP-1 cells in vitro as well as lethality in BALB/c mice. EcTx-I also induced mild myotoxic effects on mouse skin, but was devoid of hemolytic effects on human erythrocytes up to 500 μg/ml. It is shown that the toxic effect induced by E. carinatus venom is due to the presence of myotoxic PLA(2) (EcTx-I). The result also corroborates the hypothesis of an association between toxic and enzymatic domains. In conclusion, EcTx-I displays a heparin binding C-terminal region, which is probably responsible for the cytotoxic and bactericidal effects.
Acetic acid has been commonly used in medicine for more than 6000 years for the disinfection of wounds and especially as an antiseptic agent in the treatment and prophylaxis of the plague. The main goal of this study was to prove the suitability of acetic acid, in low concentration of 3%, as a local antiseptic agent, especially for use in salvage procedures in problematic infections caused by organisms such as Proteus vulgaris, Acinetobacter baumannii or Pseudomonas aeruginosa. This study was designed to compare the in vitro antimicrobial effect of acetic acid with those of common local antiseptics such as povidone-iodine 11% (Betaisodona), polyhexanide 0.04% (Lavasept), mafenide 5% and chlohexidine gluconate 1.5% cetrimide 15% (Hibicet). Former studies suggest the bactericidal effect of acetic acid, but these data are very heterogeneous; therefore, a standardised in vitro study was conducted. To cover the typical bacterial spectrum of a burn unit, the following Gram-negative and Gram-positive bacterial strains were tested: Escherichia coli, P. vulgaris, P. aeruginosa, A. baumannii, Enterococcus faecalis, Staphylococcus epidermidis, methicillin-resistant Staphylococcus aureus (MRSA) and beta-haemolytic Streptococcus group A and B. The tests showed excellent bactericidal effect of acetic acid, particularly with problematic Gram-negative bacteria such as P. vulgaris, P. aeruginosa and A. baumannii. The microbiological spectrum of acetic acid is wide, even when tested at a low concentration of 3%. In comparison to our currently used antiseptic solutions, it showed similar - in some bacteria, even better - bactericidal properties. An evaluation of the clinical value of topical application of acetic acid is currently underway. It can be concluded that acetic acid in a concentration of 3% has excellent bactericidal effect and, therefore, seems to be suitable as a local antiseptic agent, but further clinical studies are necessary.
The antimicrobial activity of extracts of Curcuma zedoaria and Curcuma malabarica tubers was tested against six bacterial and two fungal strains using the agar well diffusion and broth dilution methods. Petroleum ether, hexane, chloroform, acetone and ethanol extracts exhibited antibacterial as well as antifungal activity. Acetone and hexane extracts of both tubers showed comparable antimicrobial activity as indicated by minimum inhibitory concentration (MIC) values, but other extracts of Curcuma malabarica showed significantly lower activity than those of Curcuma zedoaria. The MIC values for different strains and extracts ranged from 0.01 to 0.15 mg/ml in Curcuma zedoaria and from 0.01 to 0.94 mg/ml in Curcuma malabarica. Staphylococcus aureus (Gram positive) was inhibited by Curcuma malabarica but not by Curcuma zedoaria. This study is the first report of the antimicrobial properties of Curcuma malabarica. The findings also support the use of Curcuma zedoaria tubers in traditional medicine for the treatment of bacterial and fungal infections.
Nutmeg (Myristica fragrans) is used in food preparations for its aromatic flavor. The present investigation was undertaken to evaluate the antibacterial activity of constituents of M. fragrans seeds. Seeds of M. fragrans were powdered and extracted with chloroform to obtain trimyristin, which on saponification yielded myristic acid. The mother liquor remaining after separation of trimyristin was concentrated and column-chromatographed with petroleum ether to separate myristicin. Antibacterial activity of these isolated constituents was evaluated by determination of minimum inhibitory concentration against selected Gram-positive and Gram-negative organisms. All the constituents isolated from nutmeg exhibited good antibacterial activity. This study shows the potential of natural compounds in replacement of synthetic preservatives.
Seasonal fluctuations of small mammal and flea communities in a Ugandan plague focus: evidence to implicate Arvicanthis niloticus and Crocidura spp. as key hosts in Yersinia pestis transmission
- Moore
Ferrara dei Censimenti, Servizio statistico nazionale
- A A Vv
Excursus sull'organizzazione dell'assistenza in tempi di pestilenza
- Sabbatani
Rodent reservoirs and flea vectors of natural foci of plague
- Gratz