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Infectious diseases in the aftermath of monsoon flooding in Pakistan

January 2012
Asian Pacific Journal of Tropical Biomedicine 2(1):76-9

DOI:10.1016/S2221-1691(11)60194-9

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PubMed

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CC BY-NC-ND 4.0

Authors:

Maryam Baqir

Aga Khan University Hospital, Karachi

Zain Sobani

Augusta University

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Pakistan is ranked 9th in terms of flood-affected countries worldwide. In the summer of 2010, the northern province of Khyber-Pakhtunkhwa received more than 312 mm of rain in a 56 hour period. This resulted in over 1 600 deaths across the region. In addition, over 14 million people were directly affected by this record-breaking deluge. Flood affected regions serve as ideal breeding grounds for pathogens, leading to the spread of diseases. The poor standards of hygiene in camps set up for individuals displaced by the floods also contribute to this. It is essential that those involved in relief efforts are aware of the epidemiology of diseases that have historically seen a sudden upsurge after natural disasters. Keeping this in mind, we conducted a simple review of literature. An extensive literature search was conducted using the PubMed data base and online search engines. Articles published in the last 20 years were considered along with some historical articles where a background was required. Seven major diseases were identified to increase substantially in the aftermath of natural disasters. They were then classified into acute and sub-acute settings. Diarrhea, skin & eye infections and leptospirosis were identified in the acute setting while malaria, leishmaniasis, respiratory infections and hepatitis were identified in the sub-acute setting.

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Infectious diseases in the aftermath of monsoon flooding in Pakistan

Maryam Baqir1, Zain A Sobani1, Amyn Bhamani2, Nida Shahab Bham1, Sidra Abid3, Javeria Farook3, M Asim Beg4*

1Aga Khan University, Karachi, Pakistan

2Barts and The London School of Medicine and Dentistry, London, England

3Dow University of Health Sciences, Karachi, Pakistan

4Department of Pathology and Microbiology, Aga Khan University, Karachi, Pakistan

Asian Pac J Trop Biomed 2012; 2(1): 76-79

Asian Pacific Journal of Tropical Biomedicine

journal homepage:www.elsevier.com/locate/apjtb

*Corresponding author: M Asim Beg, Associate Professor, Department of Pathology

and Microbiology, Aga Khan University, Karachi 74800, Pakistan.

Fax: # (92 21) 34934294

E-mail: masim.beg@aku.edu

1. Introduction

Rainfall in Pakistan varies radically from year to year.

The 3-month period from July to September is usually

marked by heavy rainfall across the country. Along with

depressions arising from the Bay of Bengal, this affects the

upper catchments of the major rivers, leading to extremely

high flood peaks and generalized flooding. An average of

579 732 people are adversely affected by this phenomenon

each year, putting Pakistan 9th in terms of flood-affected

countries worldwide[1].

This year, the northern province of Khyber Pakhtunkwa

received the highest recorded rainfall in the last 80 years.

According to estimates, over 1 600 people lost their lives in

the resulting floods, with 14 million people across the region

adversely affected[2,3]. Despite extensive relief and rescue

operations, the death toll is expected to rise as thousands

of people are still cut off from the rest of the country. The

army has predicted that rebuilding the infrastructure and

providing the people with basic necessities will take up

to 6 months[4]. During this time, it is anticipated that a

significant percentage of those affected will remain in relief

camps across the country.

Stagnant pools of flood water serve as ideal breeding

grounds for pathogens that result in diarrhea and other

waterborne infections. Cases of diarrhea, cholera and

scabies have already been reported and an outbreak of

cholera has been confirmed in Swat[2].

In this paper, we would like to review major infectious

diseases that see an upsurge in the weeks and months after

natural disasters, especially floods. For the convenience

of the reader, these have been divided into two categories:

acute and sub-acute phases. It must be emphasized,

however, that these time lines are not absolute and some

overlap exists among the phases.

2. Acute phase

2.1. Diarrhea

Flooding has been shown to cause epidemics of water and

ART ICLE INFO ABS TRACT

Article history:

Received 18 May 2011

Received in revised form 7 June 2011

Accepted 28 June 2011

Available online 28 January 2012

Keywords:

Infectious diseases

Moosoon flooding

Pakistan

Epidemiology

Natural disaster

Acute setting

Sub-acute setting

Malaria

Pakistan is ranked 9th in terms of flood-affected countries worldwide. In the summer of 2010,

the northern province of Khyber-Pakhtunkhwa received more than 312 mm of rain in a 56 hour

period. This resulted in over 1 600 deaths across the region. In addition, over 14 million people

were directly affected by this record-breaking deluge. Flood affected regions serve as ideal

breeding grounds for pathogens, leading to the spread of diseases. The poor standards of hygiene

in camps set up for individuals displaced by the floods also contribute to this. It is essential that

those involved in relief efforts are aware of the epidemiology of diseases that have historically

seen a sudden upsurge after natural disasters. Keeping this in mind, we conducted a simple

review of literature. An extensive literature search was conducted using the PubMed data base

and online search engines. Articles published in the last 20 years were considered along with

some historical articles where a background was required. Seven major diseases were identified

to increase substantially in the aftermath of natural disasters. They were then classified into acute

and sub-acute settings. Diarrhea, skin & eye infections and leptospirosis were identified in the

acute setting while malaria, leishmaniasis, respiratory infections and hepatitis were identified in

the sub-acute setting.

Contents lists available at ScienceDirect

Maryam Baqir et al./Asian Pac J Trop Biomed 2012; 2(1): 76-79 77

vector borne diseases[5]. Water-borne outbreaks of diarrheal

illness after floods are thought to result primarily from the

contamination of water. This occurs due to the disruption

of purification and sewage disposal systems. However,

secondary effects of flooding, including crowding and

subsequent fecal-oral spread of gastrointestinal pathogens,

may also contribute to the spread of diarrheal diseases[6,7].

During the July, 2004 floods in Bangladesh, outbreaks of

diarrheal diseases occurred throughout Dhaka, with more

than 17 000 patients seen at a single centre[8]. Additionally,

compared with non-flood periods, patients who presented

during the 1988, 1998 and 2004 floods due to diarrhoea

were found to be more severely dehydrated and of lower

socioeconomic status[9]. When considering embankment

structures, it was found that the crude child mortality

was significantly decreased and death rates outside the

embankment were higher[10]. However, another study showed

that the construction of flood control structures such as dams

was associated with an increase in cholera cases among

the residents protected in the long run[11]. Such a finding

requires attention from the health community, governments

and non-governmental organizations involved in ongoing

water management schemes.

The floods in Pakistan have resulted in a similar situation.

115 922 cases of acute diarrhoea had been reported in fixed

and outreach medical centres before the 12th of August.

In Khyber Pakhtunkhwa, the province worst affected,

acute diarrhoea was reported as a leading cause of illness,

accounting for 17% of medical consultations[12].

Medical teams in the region fear that cholera could spread

rapidly in the aftermath of these floods. It is thought that

the full picture will only be revealed once access to affected

areas is improved.

2.2. Skin and eye infections

Skin and eye infections often occur as a result of direct

contact with polluted water. These include wound infections,

dermatitis and conjunctivitis. However, in general, these

diseases are not known to be major causes of epidemics[13].

Extensive water damage after major hurricanes and

floods increases the likelihood of mould contamination

in buildings, exposure to which can cause adverse health

effects. Skin conditions related to this are particularly

common, regardless of the type of mould or the extent of

contamination[14]. In one study conducted in Thailand, it

was found that eczema is the most common dermatosis

during floods[15]. Topical medications that combine

antiinflammatory, antibacterial and antifungal properties are

the most suitable medications to combat this.

During the current floods, approximately 143 870 skin

infections have been reported in fixed and outreach medical

centres across the southern province of Sindh. As a group,

these are the third most common cause of illness, after

respiratory infections and acute diarrhea[12].

The risk of eye infections also mounts as torrential rains

occur. In the aftermath of floods in 1993, the University of

Iowa saw a record number of eye infections related to water-

borne pathogens[16]. The contamination of the water supply

by sewage and the prevailing high temperatures were cited

as potential reasons for this.

2.3. Leptospirosis

Leptospirosis is a common zoonotic infection in the

world[17]. Primary sources of this condition are infected

rodents and other wild animals who excrete leptospires in

their urine[18]. Once excreted, bacteria can live for a long

time in fresh water, damp soil, vegetation, and mud.

Environmental changes, including increased vector

population, facilitate the transmission during floods[13].

Human infection results from contact with carrier animals or

their environment. Additionally, contact with contaminated

water bodies is a potential cause of acquiring this

condition[19]. Drainage material contaminated with rodent

urine may also collect on roads after floods. This creates

a potential source of infection for those walking bare foot.

Children, who are attracted by puddles of rain water, are

therefore at risk.

The majority of leptospiral infections are either sub

clinical or result in very mild illness. Most patients recover

without any complications. However, a small proportion

develop complications due to the involvement of multiple

organ systems. In this case, the clinical presentation

depends upon the organs involved and the case fatality ratio

could be as high as 40%[18].

3. Sub-acute phase

3.1. Malaria

Both Plasmodium falciparum and Plasmodium vivax

are widely distributed across Pakistan due to extensive

agricultural practices, vast irrigation networks and monsoon

rains. In most parts of the country, the transmission season

is post-monsoon, occurring from July to November, with an

estimated 1.5 million cases of malaria infection occuring

annually[20].

Malaria epidemics in the wake of flooding are a well-

known phenomenon in endemic areas worldwide. These

have been seen after flooding in Costa Rica (1991), The

Dominican Republic (2004), Mandla, Benin (Annual) and

northern Peru (periodic)[13,21,22]. There is also substantial

evidence of increased malaria transmission in urban areas

of Asia as a consequence of the clogging of storm water

drains[23,24].

Locally, when torrential rain and floodwater inundated

large swathes of land in Karachi in 2006, the incidence of

malaria saw a sharp spike. It was also reported that the

prevalence of cerebral malaria had increased. Particularly

worrying was the fact that it subsequently began appearing

in resistant forms that did not respond to the conventional

therapy, enabling it to pose an even geater threat[25].

Similarly, in January, 2009, suspected malaria was

reported as the primary diagnosis in 18% of total medical

consultations in flood affected districts of Balochistan. This

made it the second leading cause of consultations[26].

Maryam Baqir et al./Asian Pac J Trop Biomed 2012; 2(1): 76-79

Interestingly, the onset of floods initially reduces mosquito

breeding. However, as the floods recede, stagnant pools

of water left behind serve as a perfect breeding ground for

malaria-causing mosquitoes. In most cases, the lag time

is usually around 6-8 weeks before the onset of a malaria

epidemic[7].

3.2. Leishmaniasis

Leishmaniasis is caused by Leishmania spp transmitted by

the sand fly. It can lead to deep, disfiguring sores at the site

of the bite, which are more likely on the exposed parts of

the body. Systemic or visceral leishmaniasis which is rarer

in Pakistan affects the internal body organs, particularly the

spleen and liver. The situation is further complicated by the

fact that very few local physicians can differentiate between

leishmaniasis and other skin diseases.

The disease is endemic in Pakistan and Afghanistan, and

its incidence has been rising[27-30]. Outbreaks have been

seen in refugee settlements along the north-western border

of Pakistan during the Afghani crisis[31]. Poor sanitation and

malnutrition also help spread the disease by providing a

habitat for the sand fly and lowering the general health of the

population, making them more susceptible. Leishmaniasis

is hence common in overcrowded, poverty stricken and

underprivileged areas with restricted access to healthcare.

Floods can potentially increase the transmission of

leishmaniasis. Bihar, a region in India endemic to floods,

has seen a surge in the disease since 1977[32]. As the relief

efforts in flood-hit Pakistan intensify, officials should brace

themselves for an outbreak of leishmaniasis among the

millions affected by the country’s worst deluge in 80 years.

To control the spread of leishmaniasis, preventive

measures similar to those used against malaria should be

implemented. Residual insecticide spray and impregnated

bed nets are effective. Even more important, however, is

improving environmental and sanitation living conditions.

3.3. Respiratory infections

In the aftermath of floods, infections of the respiratory tract

are usually amongst the most common causes of morbidity

and mortality in survivors. When devastating floods affected

millions of people in Bangladesh in 1988, it was found that

respiratory tract infections accounted for about 17.4% of all

illnesses and 13% of all reported deaths[33]. Similarly, it has

been reported that 30 new cases of tuberculosis developed

amongst 30 000 survivors of floods caused by the overflowing

Kosi River in Bihar, India in 2008. Moreover, since symptoms

of this condition may take several weeks to develop, it is

possible that these cases were just the tip of the iceberg[34].

The increased risk of respiratory tract infections is due to

the loss of shelter and exposure to flood waters and rain. In

the flood-affected communities of Pakistan, 113 981 cases of

respiratory tract infections have been reported[12]. Patients

are suffering from allergic bronchitis, asthma, chronic

obstructive pulmonary airway disease (COPD), pneumonia

and viral flu. Additionally, without proper precautions, most

of them are at risk of catching secondary infections.

Furthermore, even though there is no evidence to suggest

that corpses play a role in the development of disease

epidemics after natural disasters, workers who routinely

handle corpses may be at risk of contracting tuberculosis.

Studies suggest mycobacteria can be aerosolized when the

residual air in the lungs is exhaled during handling of the

corpse[13]. This indicates that relief workers handling corpses

may require prophylaxis.

3.4. Hepatitis

Pakistan’s already failing water and sanitation supply is

further taxed in times of natural disaster. In such situations,

water often gets contaminated by human and animal waste

carrying microorganisms with feco-oral transmission cycles.

These are capable of producing diarrhea, dysentery, and

viral hepatitis. Previous experience has shown how badly

affected the water supply in the country can be at such

times. The outbreak of acute watery diarrhea involving more

than 750 cases in the aftermath of the devastating earthquake

of 2005 is particularly relevant in this regard[35].

The potential for hepatitis A outbreaks after flood-

related sewage contamination of potable water sources has

been recognized. Increases in the incidence of hepatitis A

have been noted in association with natural disasters and

attributed to disruptions in water and sanitation facilities.

Overcrowding may also contribute[6]. Shears et al noted a

marked increase in the number of hepatitis A cases after

the Khartoum floods in 1988[36]. Similarly, after the 2005

earthquake in Pakistan, clusters of hepatitis E were common

in areas with poor access to safe water. In all, over 1 200

cases of acute jaundice, many confirmed as hepatitis E,

occurred among the displaced.

It is essential that adequate sanitary and hygienic

provisions are made in flood affected regions. This would

significantly reduce the morbidity and mortality associated

with viral hepatitis. It is also worth mentioning that Watson,

in his review, states that although hepatitis A may be

an issue during floods, most of the adult population in

developing countries will possess a degree of immunity to it.

This is due to the endemic nature of the disease[40].

4. Conclusion

Despite great advances in medicine over the past few

decades, medical complications arising from natural

disasters are still extremely common. These are particularly

problematic for developing countries like Pakistan where

resources are limited and the infrastructure weak. The recent

floods that have inundated vast portions of the country have

only served to highlight the inadequacies within the health

system. With public health spending currently standing

at 2% of the country’s GDP, it is obvious that more can be

done in order to protect those affected by these disasters

from the adverse effects of the conditions described above.

Unfortunately, awareness of these conditions is something

that is lacking in the general population. It is, therefore,

imperative that this is promptly addressed in order to

Maryam Baqir et al./Asian Pac J Trop Biomed 2012; 2(1): 76-79 79

prevent a repeat of the humanitarian crisis currently being

witnessed in much of the country.

Conflict of interest statement

We declare that we have no conflict of interest.

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May 2024

Introduction Infectious diarrhea, a significant global health challenge, is exacerbated by flooding, a consequence of climate change and environmental disruption. This comprehensive study aims to quantify the association between flooding events and the incidence of infectious diarrhea, considering diverse demographic, environmental, and pathogen-specific factors. Methods In this systematic review and meta-analysis, adhering to PROSPERO protocol (CRD42024498899), we evaluated observational studies from January 2000 to December 2023. The analysis incorporated global data from PubMed, Scopus, Embase, Web of Science, and ProQuest, focusing on the relative risk (RR) of diarrhea post-flooding. The study encompassed diverse variables like age, sex, pathogen type, environmental context, and statistical modeling approaches. Results The meta-analysis, involving 42 high-quality studies, revealed a substantial increase (RR = 1.40, 95% CI [1.29–1.52]) in the incidence of diarrhea following floods. Notably, bacterial and parasitic diarrheas demonstrated higher RRs (1.82 and 1.35, respectively) compared to viral etiologies (RR = 1.15). A significant sex disparity was observed, with women exhibiting a higher susceptibility (RR = 1.55) than men (RR = 1.35). Adults (over 15 years) faced a greater risk than younger individuals, highlighting age-dependent vulnerability. Conclusion This extensive analysis confirms a significant correlation between flood events and increased infectious diarrhea risk, varying across pathogens and demographic groups. The findings highlight an urgent need for tailored public health interventions in flood-prone areas, focusing on enhanced sanitation, disease surveillance, and targeted education to mitigate this elevated risk. Our study underscores the critical importance of integrating flood-related health risks into global public health planning and climate change adaptation strategies.

Profile of dermatoses in extreme weather events: case series during floods in the state of Rio Grande do Sul, Brazil

Article

Feb 2025

Impact of Ayurveda Pre-monsoon Prophylaxis on Episodes and Severity of Fever, Cough and Cold in North Karnataka - A Cross-sectional Survey Study

Article

Full-text available

Jun 2024

Background: Though monsoons are a real gift of nature, it is a meteorological phenomenon which brings in lots of losses in terms of money and life through the upsurge of various infectious diseases in India. According to Ayurveda, immunity is comparatively lower during the monsoon season. So, it is in practice in our institute to provide pre-monsoon prophylaxis to all interested staff and students to boost immunity. Objective: The present retrospective cross-sectional study was planned to assess the impact of Ayurveda Pre-monsoon Prophylaxis on the severity and frequency of episodes of fever, cough and cold in healthy volunteers. Methods: After obtaining ethical clearance for the cross-sectional study, a survey using Google Forms was conducted. A Google form was created to assess the health condition as well as the frequency and severity of cough, cold and fever in the study subjects before and after prophylaxis. Detailed scrutiny of the respondents was carried out by the investigators. The Google forms of people who participated in the prophylaxis and visited for follow-up six months after receiving monsoon prophylaxis were included in the analysis. The data was analyzed using paired t-test. Results: A total of 591 participants out of 806 met the inclusion criteria and participated in the study. A highly significant (p<0.001) reduction in the frequency of episodes and severity of fever, cold, and cough was found in the study subjects after prophylaxis. Conclusion: So, it may be inferred that Ayurveda Pre-monsoon prophylaxis is an effective practice to enhance overall health and thereby boost the immunity of individuals.

Exploring the Association Between Floods and Diarrhea among Under-five Children in Rural India

Article

Full-text available

Oct 2024

Objective: Flood is one of the major public health concerns increasing the risk of childhood diarrhea. This study aims to explore the association of floods with diarrhea among under-five children in rural India. Methods:Across-sectional study was carried out using large-scale nationally representative data from the National Family Health Survey-5. The Central Water Commission reports between the years 2018 and 2020 were used to group all the districts as non-flood-affected districts or floodaffected districts. Bivariate and multivariate logistic regression models were employed to assess the association of floods with childhood diarrhea. Results: The prevalence of diarrhea was higher among children exposed to three consecutive floods during the year 2019-21 than those children not exposed to flood. Children exposed to flood three times between the year 2018-19 to 2020-21 were associated with a 34% higher likelihood of developing diarrhea than those children exposed to flood one or two times. Conclusions: Our study suggests that community health workers should target mothers belonging to the poor wealth quintile, young mothers, and mothers with young infants and more children to receive child health related counseling in flood-prone areas.

A global attribution analysis of increasing risk of successive runoff-heat extreme events driven by anthropogenic forcing

Article

Aug 2024
J HYDROL

The successive runoff-heat extreme (SRHE) events, defined as the occurrence of an extreme runoff event followed by a heatwave event, have become more frequent under recent global warming. However, the impact of anthropogenic climate change (ACC) on global changes in SRHE characteristics during the past decades remains unclear. Here, we evaluate the impact of ACC on SRHE frequency and characteristics during 1950–2014, based on the daily maximum and minimum temperature and total runoff data simulated by five global climate models (GCMs) from the Coupled Model Intercomparison Project Phase 6 (CMIP6) under the “anthropogenic and natural both (ALL)” and “natural only (NAT)” experiments. Attribution of SRHE changes with different durations and intervals between extreme runoff and heatwave (IRHs) is achieved by using the fraction attributable risk (FAR) method. Results indicate that ACC exacerbates SRHE occurrence for most global regions, especially in the Southern Hemisphere (>60 % increase in probability), but the spatial variability of this impact decreases over time. The globally-average probability of SRHE occurrence due to ACC has increased significantly by 40 % during 1971–2014 (∼10 %/decade), and the probability of SRHE with the short IRHs and long duration tends to be larger than other types of SRHE. ACC also prolongs the duration of SRHE in most global regions, with an increase of 1–4.5 folds in northern South America, central Africa, and southeast Asia during 1950–2014. Partial correlation analysis indicates that the intensification of heatwave due to ACC contributes more than that of extreme runoff to SRHE occurrence in nearly all global regions, particularly in the Southern Hemisphere.

Protection from annual flooding is correlated with increased cholera prevalence in Bangladesh: A zero-inflated regression analysis

Article

Full-text available

Mar 2010
ENVIRON HEALTH-GLOB

Alteration of natural or historical aquatic flows can have unintended consequences for regions where waterborne diseases are endemic and where the epidemiologic implications of such change are poorly understood. The implementation of flood protection measures for a portion of an intensely monitored population in Matlab, Bangladesh, allows us to examine whether cholera outcomes respond positively or negatively to measures designed to control river flooding. Using a zero inflated negative binomial model, we examine how selected covariates can simultaneously account for household clusters reporting no cholera from those with positive counts as well as distinguishing residential areas with low counts from areas with high cholera counts. Our goal is to examine how residence within or outside a flood protected area interacts with the probability of cholera presence and the effect of flood protection on the magnitude of cholera prevalence. In Matlab, living in a household that is protected from annual monsoon flooding appears to have no significant effect on whether the household experiences cholera, net of other covariates. However, counter-intuitively, among households where cholera is reported, living within the flood protected region significantly increases the number of cholera cases. The construction of dams or other water impoundment strategies for economic or social motives can have profound and unanticipated consequences for waterborne disease. Our results indicate that the construction of a flood control structure in rural Bangladesh is correlated with an increase in cholera cases for residents protected from annual monsoon flooding. Such a finding requires attention from both the health community and from governments and non-governmental organizations involved in ongoing water management schemes.

Flood control embankments contribute to the improvements of health status of children in rural Bangladesh

Article

Full-text available

Jan 1997
B WORLD HEALTH ORGAN

Every year, Bangladesh experiences major floods that inundate about one-third of the country. Therefore, flood control projects that comprise earthen dikes and irrigation/drainage systems are built along the major rivers to protect the people living in low-lying areas, stabilize the river banks and improve agricultural productivity. However, the adverse effects of these projects are regularly emphasized, such as environmental degradation and reduction of fishing supplies. The Demographic Surveillance System of the International Centre for Diarrhoeal Diseases Research, Bangladesh (ICDDR,B) was used to assess the effect of a flood control programme on the mortality of 0-4-year-old children residing in the Matlab study area. Adjusted mortality rates were used in comparing four adjacent child populations residing either inside or outside a flood-control embankment and according to the type of health services provided in this area. Between the periods 1983-86 and 1989-92, the crude child mortality in the total study area decreased by 37%, from 185.9 per 1000 live births to 117.9 per 1000 live births. Following the construction of the embankment, death rates outside were up to 29% higher in 1-4-year-old children and 9% higher for 0-4-year age group compared to the flood-protected area (P < 0.001). Simultaneously, in the same study area, health interventions contributed to a 40% reduction in mortality among children less than 5 years of age in all causes of deaths (P < 0.001). Migration patterns and the effect of distances to the hospital are discussed.

1988 floods in Bangladesh: Pattern of illness and causes of death

Article

Full-text available

Jan 1992
J Diarrhoeal Dis Res

The worst flood in the history of Bangladesh affected millions of people in 1988. To determine morbidity and mortality during the flood, we investigated the causes of illness in 46,740 patients and causes of death in 154 persons while providing medical relief services in 72 flood affected upazilas (sub-districts). Diarrhoea was the most common illness (34.7%), followed by respiratory tract infections (17.4%). Watery diarrhoea was the most common type (47%) of diarrhoea and the most common cause of death for all age groups except those above 45-years of age. Respiratory disease was responsible for 13% of all reported deaths; only 7% of these were associated with acute respiratory tract infections. Accidental deaths accounted for 9.7% of the reported deaths: 5.8% of those were due to drowning, a figure twice as high as that reported previously. Our study suggests that floods have influenced the distribution of disease and death among the affected population.

Storage logistic stocking flow desgin based on RFID technology[J]

Article

Jan 2006

Outbreak of falciparum malaria in submerged villages of Narayanganj PHC, district Mandla due to Narmada Irrigation Project, Central India (Madhya Pradesh)

Article

Oct 1997
CURR SCI INDIA

On receipt of a report about high prevalence of malaria and deaths in submerged villages of Narayanganj Primary Health Centre (PHC) of district Mandla, Central India (Madhya Pradesh) due to Bargidam in October-November 1996, an investigation into the causes was carried out in 20 villages. Blood smears from fever cases and contacts of deceased patients were collected. Slide positivity rate was over 70%, of which more than 90% was Plasmodium falciparum. Mass blood surveys of infant and pregnant women revealed 39% and 62% parasite prevalence rate respectively. More than 80% children (2-9 yrs) had enlarged spleen. Such high malaria prevalence appeared to be maintained by Anopheles culicifacies and An. fluviatilis which could not be suppressed by intensive surveillance, prompt radical treatment with 1500 mg chloroquine and 45 mg primaquine and two rounds of special focal spray with DDT in October 1996 and January 1997. There is, therefore, an urgent need to develop suitable malaria control strategy by replacement of insecticides in conjunction with prompt and effective radical treatment.

The impact on health and risk factors of the diarrhoea epidemics in the 1998 Bangladesh floods

Article

Mar 2002
PUBLIC HEALTH

Osamu Kunii

The 1998 flood in Bangladesh ravaged approximately 60% of the land and affected over 30 million people. The aim of this study is to examine the impact of the flood on the health of the communities affected and to explore factors associated with episodes of diarrhoea.We conducted structured interviews with 517 people in two districts that had been affected in October 1998, when the flood water level was at its peak. Of the 517 respondents, 98.3% developed health problems or found that existing health problems were exacerbated. Many perceived that their general health condition was ‘much worse’ (16.9%) or ‘worse’ (64.3%). The most prevalent condition was fever (63.6%), followed by respiratory problems (46.8%), diarrhoea (44.3%), and skin problems (41.0%). Only 1.0% and 6.7% of the respondents treated water before drinking, by boiling and chlorination, respectively, although water collected from tube-wells (93.2%) and rivers (6.0%) was perceived by 75.0% of the respondents to be contaminated.Factors associated with developing or worsening diarrhoea were as follows; the number of family members, poor economic status, a lack of distribution of water purification tablets, the type of water storage vessels, not putting a lid on the vessel, no use of latrines, perceived change of drinking water, food scarcity, and worries about the future. In logistic regression analysis, men, poor economic status, lack of distribution of water purification tablets, and the type of water storage vessels had a significant association with diarrhoea.The 1998 Bangladesh flood had a substantial impact on the health of communities. Diarrhoea was associated with socioeconomic status, water handling and household sanitation. There ought to be more emphasis on health education in the pre-disaster period in order to empower communities against floods. Public Health (2002) 116, 68–74

Leptospirosis: An emerging global public health problem

Article

Dec 2008

Leptospirosis has been recognized as an emerging global public health problem because of its increasing incidence in both developing and developed countries.A number of leptospirosis outbreaks have occurred in the past few years in various places such as Nicaragua, Brazil and India.Some of these resulted due to natural calamities such as cyclone and floods. It is a direct zoonotic disease caused by spirochetes belonging to different pathogenic species of the genus Leptospira. Large number of animals acts as carriers or vectors.Human infection results from accidental contact with carrier animals or environment contaminated with leptospires. The primary source of leptospires is the excretor animal, from whose renal tubules leptospires are excreted into the environment with the animal urine. Majority of leptospiral infections are either sub clinical or result in very mild illness and recover without any complications.However,a small proportion develops various complications due to involvement of multiple organ systems. In such patients, the clinical presentation depends upon the predominant organs involved and the case fatality ratio could be about 40% or more. Febrile illness with icterus, splenomegaly and nephritis (known as Weil's disease), acute febrile illness with severe muscle pain,febrile illness with pulmonary haemorrhages in the form of haemoptysis, jaundice with pulmonary haemorrhages, jaundice with heamaturea, meningitis with haemorrhages including sub conjunctival haemorrhage or febrile illness with cardiac arrhythmias with or without haemorrhages are some of the syndromes. Because of the protean manifestations of leptospirosis it is often misdiagnosed and under-reported. Although the basic principles of prevention such as source reduction,environmental sanitation, more hygienic work-related and personal practices etc., are same everywhere, there is no universal control method applicable to all epidemiological settings. Comprehensive understanding of the eco-epidemiological and cultural characteristics of a community that faces the problem of leptospirosis is an essential prerequisite for evolving an effective and acceptable control measure.

Epidemic of malaria in Barmer District (Thar desert) of Rajasthan during 1990

Article

Apr 1992
Indian J Malariol

Barmer district of Rajasthan in Thar desert and hitherto a hypoendemic area for malaria came in the grip of a severe malaria epidemic during 1990. The epidemic occurred as an aftermath of floods, preceded by normal rains during 1988 and 1989 after a prolonged drought phase. The epidemic was spread over the whole district including Barmer town. Annual Parasite Incidence (API) and Annual falciparum Incidence (AFI) for the district touched record figures of 17.20 and 5.83 respectively while for the Barmer town they were 36.5 and 14.0 respectively. Out of the eight PHCs, Baitu PHC was the worst affected where the two indices touched all-time high figures of 55.3 and 19.6 per cent respectively. A total of 122 infants were reported positive for malaria, of which 103 were contributed by Baitu PHC alone. Eighty per cent infant positivity was spread over September and November, indicating a high rate of transmission. A total of 47 deaths due to cerebral malaria were reported. However, in view of the high infectivity among infants and paediatric groups there was a strong possibility of deaths among these groups which could not be verified. Entomological findings revealed that a sudden increase in An. culicifacies densities due to extensive breeding potential, as a sequel to floods, activated the transmission, which was maintained at a low level by An. stephensi, predominant in this desert region. Other factors which contributed to the intensity and extent of epidemic were the return of drought-migrated population from malarious areas, low cattle density, malaria non-immune population, inadequate and poor spray coverage and delayed radical treatment. Insecticide adult susceptibility tests revealed a high degree of resistance in An. stephensi against DDT and dieldrin.

Infectious disease following major disasters

Article

May 1992
ANN EMERG MED

A recent surge in the general awareness of the extent of disasters has increased concern over the adequacy of our state of preparedness for these events. Outbreaks of infectious disease after a disaster may have significant societal impacts. In preparation, rescuers must anticipate and identify infectious risks, isolate and treat the individuals with infections, and institute measures that will prevent the further spread of infectious diseases. Epidemiological factors may contribute to the spread of infectious disease after a given disaster. A simple microbiological laboratory in the field may be helpful in attempting to direct therapy at specific infectious etiologies. Prior post-disaster experience suggests that mass immunization may not always be valuable in protecting against disease spread acutely, although immunizations may be considered in a limited number of situations. Disaster medical personnel should prepare themselves with appropriate vaccinations and remain in good health; new pathogens must not be brought in by well-meaning relief personnel. Disasters often occur in a Third-World setting where resources are limited and often compromised. Complete recovery from infectious disease outbreaks and restoration of infection control practices may take years when a Third-World population has suffered a major disaster.

The Khartoum floods and diarrhoeal diseases

Article