What role for insecticides in vector control programs?
ABSTRACT Vector-borne diseases including dengue, yellow fever, Japanese encephalitis, malaria, leishmaniasis, and filariasis remain severe public health problems in most of the countries in which they are endemic. In some cases, their incidence is increasing and they are spreading to new geographic areas. For a number of the infections, the most effective manner of controlling their transmission is through control of their vectors. However, in some instances, such as dengue and Chagas' disease, there is no alternative. Most countries that are endemic for vector-borne diseases maintain vector control services, and most large tropical and semitropical cities also have pest control programs, mainly against pest mosquitoes. Virtually all of the vector and pest control programs depend on the use of insecticides formulated as larvicides, adulticides, baits, or insecticide impregnated bed nets. For many years, the development of new insecticides for use in public health programs was encouraged and supported by multilateral and bilateral health agencies, including the implementation of field trials in endemic areas. Due to the development of insecticide resistance, toxicologic and environmental considerations, and the cost of development and of registration, the number of compounds available for use has declined while the number of new insecticides submitted for laboratory and field trials to the World Health Organization has dwindled even more. The recrudescence of vector-borne diseases, the rapid pace of urbanization, lagging development of environmental services in many tropical cities, and difficulties encountered in ensuring the community's cooperation in its own protection through environmental measures make imperative the continued availability of pesticides for public health use. Since only the pesticide manufacturing industry has the combination of technical and financial resources to promulgate the research and development of new pesticides and pesticide groups, it is suggested that governments, bilateral, and multilateral organizations explore the manner in which they can assist industry in the development of new compounds and guarantee the continued availability of effective and safe pesticides for vector-control programs.
- SourceAvailable from: Karunamoorthi Kaliyaperumal[show abstract] [hide abstract]
ABSTRACT: Context: Arthropod-borne diseases are remaining as a major public health issue in the resource-constrained settings. Mosquitoes are closely associated with mankind since time immemorial and play an important role in the transmission of many dreadful diseases like malaria, filariasis, Japanese encephalitis, dengue and yellow fever. Over the decades, vector control is an important element to minimize the vector-borne disease burden worldwide and in fact, it heavily relies upon synthetic insecticides as a mainstay. However the overuse and misuse of insecticides have led to the emergence of resistance, which undermines the potentiality of vector control. Evidence Acquisition: In order to pursue effective research pertained to this issue, a detailed search on Scopus, Medline, Google Scholar and academic premier databases has been conducted between the time periods of 1955 and 2012. Results: Over the past six decades, insecticides are serving as one of the important arsenals in the fight against vector-borne diseases to save hundreds of millions of lives. Consequently, in the last decade we have attained a remarkable success to combat with many diseases particularly malaria due to the combined effect of indoor residual spraying (IRS) and long-lasting insecticidal nets (LLINs). Currently, malaria mortality rates have drastically fallen by more than 25% globally, 33% in sub-Saharan Africa and over a million lives have been saved attributable to massive scale-up of LLINs and IRS. Since, both LLINs and IRS are cost-effective and robust form of interventions; they are serving as a central pillar in the National Malaria Control Programmes (NMCPs) of malaria endemic countries. Nevertheless, LLINs are easy-to-deliver, most economical and practical even in the resource-poor settings, where implementation of IRS is not feasible. The heavy reliance, recurrent and inappropriate insecticide applications are key sources for resistance which is a potential threat to the global public health. Therefore, it has to be addressed immediately to sustain the recent success of vector control, unless otherwise it would become uncertain. Conclusions: Though, development of resistance is an evolutionary phenomenon, it can be tackled judiciously by implementing appropriate and comprehensive resistance monitoring and management strategies within the framework of integrated vector management. This scrutiny recommends the following measures; (i) identification of effective novel tools for monitoring and evaluation, (ii) searching for alternative interventions to minimize the further resistance evolution as well as to preserve the efficiency of existing insecticides, (iii) exploration of next generation vector control tools in terms of nets and new classes of non-pyrethroid insecticide formulation with new mode of action, (iv) building partnership by bringing together the people actively engaged in the vector control, like public health experts, policy-makers, researchers, medical entomologists and insecticide manufacturers, could ideally pave the way to collectively address the current debacle in the near future.Health Scope. 01/2013; 2(1):4-18.
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ABSTRACT: Recent development of 3-dimensional analysis of eye movement enabled to detect the eye rotation axis, which is used to determine the responsible semicircular canal(s) in dizzy patients. Therefore, the knowledge of anatomical orientation of bilateral semicircular canals is essential, as all 6 canals influence the eye movements. Employing the new head coordinate system suitable for MR imaging, we calculated the angles of semicircular canal planes of both ears in 11 dizzy patients who had normal caloric response in both ears. The angles between adjacent canal pairs were nearly perpendicular in both ears. The angle between the posterior canal planes and head sagittal plane was 51° and significantly larger the angle between the anterior canal planes and head sagittal plane, which was 35°. The angle between the horizontal canal plane and head sagittal plane was almost orthogonal. Pairs of contralateral synergistic canal planes were not parallel, forming 10° between right and left horizontal canal planes, 17° between right anterior and left posterior canal planes and 19° between the right posterior and left anterior canal planes. Our measurement of the angles of adjacent canal pairs and the angle between each semicircular canal and head sagittal plane coincided with those of previous reports obtained from CT images and skull specimens. However, the angles between contralateral synergistic canal planes were more parallel than those of previous reports.Auris, nasus, larynx 11/2011; 39(5):451-4. · 0.58 Impact Factor
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ABSTRACT: Background: Occupational insecticidal poisoning (OIP) is a global phenomenon, which is even more prevalent among indoor residual spray-workers and this can pose a serious threat to their health. Objectives: This study aimed to assess spray-workers' management of insecticide risk indicators and occupational insecticidal poisoning. Materials and Methods: An analytical cross-sectional survey was adopted, that involved all of the professional indoor residual spray-workers serving in the Omo-Nada woreda (district), Ethiopia. The survey was conducted between January and April 2011 by administering a pre-tested questionnaire. All statistical analyses were performed by using SPSS v.19.0. A two-sided Fisher's exact test was performed to determine associations between the variables. Results: Overall, 52.4% of the study participants had an awareness of the usage of personal protective equipment (PPE), whereas 41.9% were unable to read the pesticide labels. About 75.3% of spray-workers never drink or eat or smoke, while spraying. Statistical analysis (two-sided Fisher's exact test) confirmed that there is no statistically significant association between safe insecticide practice with the spray-worker's gender (P = 0.332), whereas, there were strong correlations found with age (P = 0.001), educational status (P = 0.001) and years of work experience (P = 0.001). Conclusions: Despite adequate awareness of safe insecticide management, most of the spray-workers were observed to be reluctant to put this knowledge into practice, either due to the inadequacy of PPE or negligence. Furthermore, a sizable faction of these workers still had limited knowledge and erroneous risk perceptions, thus increasing their risk of OIP. Therefore, appropriate communication strategies and training could reduce the occupational risk of insecticide exposure, which would ultimately minimize the related health hazards of insecticidal poisoning.; DOI: 10.5812/jhs.8344 Implication for health policy/practice/research/medical education: The content and results of the present communication has identified the risk indicators and it is useful for the policy/decision mak-ers to reduce the occupational insecticidal poisoning.