Cholera Incidence Research Articles

Epidemic cholera in complex emergencies

Complex emergencies are situations of violence, nutritional insecurity and population displacement of increasing frequency and intensity which pose a serious public health problem to the affected populations. Communicable diseases, especially waterborne diseases as cholera, cause up to 75% of morbidity and mortality in complex emergencies. The objective is to analyze the cholera epidemics in complex emergencies and cholera risk factors associated with the emergency. This descriptive study analyzes cholera epidemics in complex emergencies in affected countries between 2000 and 2011 by reviewing the information formally published and unpublished reports from field organizations and aid agencies. Indicators of incidence, mortality and case-fatality were used. The mean annual incidence of cholera in areas of complex emergency was 1.2 per 1,000 population (95% CI = 0.5 to 1.9) and the average fatality of epidemics was 4.08% (95% CI = 3.3 to 4.86). In the cases studied the following specific risk factors of complex emergencies are present and amplify the impacts of cholera: serious deficiencies in water and sanitation, over-crowding, weak health system, lack of previous immunity of the affected population and introduction or reintroduction of causative agent.

Cholera resurgence in Piura, Peru: examining climate associations during the 1997–1998 El Niño

In Peru, the climate pattern El Nino-Southern Oscillation (ENSO) was linked to a resurgence of cholera in 1998. While previous studies found a temperature connection, El Nino’s impact on cholera in Peru has not been fully explored. In this study, climate associations with cholera incidence during the 1997–1998 El Nino are examined at a district-level in Piura, a coastal area located in northern Peru. Piura is important to study because it was one of the most affected areas by cholera and El Nino in 1998. The approach taken in this study is a “multiple pathways” perspective, which highlights various dimensions of ENSO to explain cholera linkages. Associations were estimated at various temporal lags using bivariate regression and then mapped in ArcGIS. The results show significant cholera associations with SST in the central equatorial Pacific and on the coast (0–1 month lag), rainfall (1 month lag), and mean and maximum temperatures (5 month lags). Overall, the strongest consistent impact was rainfall, which supports the notion that flooding was a pathway for cholera exposure in Piura. Local sea and air temperature associations also suggest that exposure was potentially linked to vibrio proliferation, which increased the probability of cholera risk. Furthermore, this study shows that climate impacts on cholera were unevenly distributed across Piura, indicating that some districts were more vulnerable than others, possibly related to infrastructure deprivation. In conclusion, the study provides a basis for future investigations, which may be useful for epidemic preparedness during future El Ninos and other extreme climate events.

An Optimal Cost Effectiveness Study on Zimbabwe Cholera Seasonal Data from 2008–2011

Incidence of cholera outbreak is a serious issue in underdeveloped and developing countries. In Zimbabwe, after the massive outbreak in 2008–09, cholera cases and deaths are reported every year from some provinces. Substantial number of reported cholera cases in some provinces during and after the epidemic in 2008–09 indicates a plausible presence of seasonality in cholera incidence in those regions. We formulate a compartmental mathematical model with periodic slow-fast transmission rate to study such recurrent occurrences and fitted the model to cumulative cholera cases and deaths for different provinces of Zimbabwe from the beginning of cholera outbreak in 2008–09 to June 2011. Daily and weekly reported cholera incidence data were collected from Zimbabwe epidemiological bulletin, Zimbabwe Daily cholera updates and Office for the Coordination of Humanitarian Affairs Zimbabwe (OCHA, Zimbabwe). For each province, the basic reproduction number () in periodic environment is estimated. To the best of our knowledge, this is probably a pioneering attempt to estimate in periodic environment using real-life data set of cholera epidemic for Zimbabwe. Our estimates of agree with the previous estimate for some provinces but differ significantly for Bulawayo, Mashonaland West, Manicaland, Matabeleland South and Matabeleland North. Seasonal trend in cholera incidence is observed in Harare, Mashonaland West, Mashonaland East, Manicaland and Matabeleland South. Our result suggests that, slow transmission is a dominating factor for cholera transmission in most of these provinces. Our model projects cholera cases and cholera deaths during the end of the epidemic in 2008–09 to January 1, 2012. We also determine an optimal cost-effective control strategy among the four government undertaken interventions namely promoting hand-hygiene & clean water distribution, vaccination, treatment and sanitation for each province.

Impact of Flooding on the Health of Coastal Fishing Folks in Epe Division of Lagos State, Nigeria

There have been predictions that the impact of global warming would put several inhabitants of coasts at serious risk of flooding. This paper analyzed the impact of flooding on coastal fishing folks in Lagos state. The data were collected with simple random sampling and analyzed with simple descriptive statistics and Probit regression. Results showed that average fishing experience was about 10 years and 14.89 percent had their water contaminated during flooding. Also, 27.66 percent spent more on health during flooding while 27.66 percent, 25.53 percent and 23.40 percent reported that diarrhea, typhoid fever and cholera became more prominent after flooding. Also, 40.43 percent indicated that members between 40<65 years were mostly affected by flooding. The Probit regression results revealed that parameters of water contaminated during flooding, single mar ital status, number of female, income, fishing experience, cholera incidence and climate change affects 40<65 yea rs most increased likelihoods of spending more on health during flooding, while male household headship, diarrhea incidence and climate change affects 19<40 years most reduced it. It was concluded that intervention preparedness to address water needs of households will help in reducing the health impacts of flooding.

Elimination of Cholera in the Democratic Republic of the Congo: The New National Policy

We evaluated published and unpublished data on cholera cases and deaths reported from clinical care facilities in the 56 health districts of the Democratic Republic of Congo to the National Ministry of Health during 2000-2011. Cholera incidence was highest in the eastern provinces bordering lakes and epidemics primarily originated in this region. Along with a strong seasonal component, our data suggest a potential Vibrio cholerae reservoir in the Rift Valley lakes and the possible contribution of the lakes' fishing industry to the spread of cholera. The National Ministry of Health has committed to the elimination-rather than control-of cholera in DRC and has adopted a new national policy built on improved alert, response, case management, and prevention. To achieve this goal and implement all these measures it will require strong partners in the international community with a similar vision.

Cholera in Coastal Africa: A Systematic Review of Its Heterogeneous Environmental Determinants

According to the "cholera paradigm," epidemiology of this prototypical waterborne disease is considered to be driven directly by climate-induced variations in coastal aquatic reservoirs of Vibrio cholerae. This systematic review on environmental determinants of cholera in coastal Africa shows that instead coastal epidemics constitute a minor part of the continental cholera burden. Most of coastal cholera foci are located near estuaries, lagoons, mangrove forests, and on islands. Yet outbreaks often originate in coastal cities, where cholera is more likely to be imported from distant areas. Cholera outbreaks also may intensify in densely populated slum quarters before spreading to adjacent regions. Frequent seasonality of cholera incidence appears driven by the rainfall-induced contamination of unprotected water sources through latrine overflow and sewage, as well as by the periodicity of human activities like fishing or traveling. Lulls in transmission periods of several years are repeatedly recorded even in high-risk coastal areas. To date, environmental studies have failed to demonstrate a perennial aquatic reservoir of toxigenic V. cholerae around the continent. Finally, applicability of the cholera paradigm therefore appears questionable in Africa, although available data remain limited. Thorough surveys with microbiological analyses of water samples and prospective genotyping of environmental and clinical strains of V. cholerae are needed to understand determinants of cholera in coastal Africa and better target prevention and control measures.

National Surveillance Data on the Epidemiology of Cholera in Togo

Togo is a cholera-endemic country bordered by other countries where this disease is endemic. We describe the epidemiology of cholera in Togo, using national surveillance data. We reviewed national surveillance data housed in the National Ministry of Health. Districts submitted reports of summary weekly case counts and deaths at the national level. Data were available at the district level during 2008-2010 and at the national level from 1996 onward. Microbiological confirmation usually was not performed, and case identification was based on clinical suspicion. From 1996 through 2010, Togo had 12 676 reported cholera cases and 554 deaths. Annual national cholera incidence varied from 0.9 to 66 cases per 100 000 population, with little variation except for 2 large epidemics during 1998 and 2001. The case-fatality ratio declined from 12%-17% during 1996-1997 to <1% during 2008-2010. During 2008-2010, 85% of 26 district-level outbreaks occurred in the capital Lomé or the coastal Maritime Region. The average outbreak duration was 6 weeks, and only 2 lasted >15 weeks. While cholera control remains elusive in Togo, reductions in case-fatality ratios have occurred, possibly due to improvements in case management. The short duration of outbreaks may preclude reactive vaccination; however, the restricted geographic location may make preventive immunization attractive.

Examining rainfall and cholera dynamics in Haiti using statistical and dynamic modeling approaches

Haiti has been in the midst of a cholera epidemic since October 2010. Rainfall is thought to be associated with cholera here, but this relationship has only begun to be quantitatively examined. In this paper, we quantitatively examine the link between rainfall and cholera in Haiti for several different settings (including urban, rural, and displaced person camps) and spatial scales, using a combination of statistical and dynamic models.Statistical analysis of the lagged relationship between rainfall and cholera incidence was conducted using case crossover analysis and distributed lag nonlinear models. Dynamic models consisted of compartmental differential equation models including direct (fast) and indirect (delayed) disease transmission, where indirect transmission was forced by empirical rainfall data. Data sources include cholera case and hospitalization time series from the Haitian Ministry of Public Health, the United Nations Water, Sanitation and Health Cluster, International Organization for Migration, and Hôpital Albert Schweitzer. Rainfall data was obtained from rain gauges from the U.S. Geological Survey and Haiti Regeneration Initiative, and remote sensing rainfall data from the National Aeronautics and Space Administration Tropical Rainfall Measuring Mission.A strong relationship between rainfall and cholera was found for all spatial scales and locations examined. Increased rainfall was significantly correlated with increased cholera incidence 4–7 days later. Forcing the dynamic models with rainfall data resulted in good fits to the cholera case data, and rainfall-based predictions from the dynamic models closely matched observed cholera cases. These models provide a tool for planning and managing the epidemic as it continues.

5 year efficacy of a bivalent killed whole-cell oral cholera vaccine in Kolkata, India: a cluster-randomised, double-blind, placebo-controlled trial

Efficacy and safety of a two-dose regimen of bivalent killed whole-cell oral cholera vaccine (Shantha Biotechnics, Hyderabad, India) to 3 years is established, but long-term efficacy is not. We aimed to assess protective efficacy up to 5 years in a slum area of Kolkata, India. In our double-blind, cluster-randomised, placebo-controlled trial, we assessed incidence of cholera in non-pregnant individuals older than 1 year residing in 3933 dwellings (clusters) in Kolkata, India. We randomly allocated participants, by dwelling, to receive two oral doses of modified killed bivalent whole-cell cholera vaccine or heat-killed Escherichia coli K12 placebo, 14 days apart. Randomisation was done by use of a computer-generated sequence in blocks of four. The primary endpoint was prevention of episodes of culture-confirmed Vibrio cholerae O1 diarrhoea severe enough for patients to seek treatment in a health-care facility. We identified culture-confirmed cholera cases among participants seeking treatment for diarrhoea at a study clinic or government hospital between 14 days and 1825 days after receipt of the second dose. We assessed vaccine protection in a per-protocol population of participants who had completely ingested two doses of assigned study treatment. 69 of 31 932 recipients of vaccine and 219 of 34 968 recipients of placebo developed cholera during 5 year follow-up (incidence 2·2 per 1000 in the vaccine group and 6·3 per 1000 in the placebo group). Cumulative protective efficacy of the vaccine at 5 years was 65% (95% CI 52-74; p<0·0001), and point estimates by year of follow-up suggested no evidence of decline in protective efficacy. Sustained protection for 5 years at the level we reported has not been noted previously with other oral cholera vaccines. Established long-term efficacy of this vaccine could assist policy makers formulate rational vaccination strategies to reduce overall cholera burden in endemic settings. Bill & Melinda Gates Foundation and the governments of South Korea and Sweden.

Modeling the effect of water, sanitation, and hygiene and oral cholera vaccine implementation in Haiti.

In 2010, toxigenic Vibrio cholerae was newly introduced to Haiti. Because resources are limited, decision-makers need to understand the effect of different preventive interventions. We built a static model to estimate the potential number of cholera cases averted through improvements in coverage in water, sanitation and hygiene (WASH) (i.e., latrines, point-of-use chlorination, and piped water), oral cholera vaccine (OCV), or a combination of both. We allowed indirect effects and non-linear relationships between effect and population coverage. Because there are limited incidence data for endemic cholera in Haiti, we estimated the incidence of cholera over 20 years in Haiti by using data from Malawi. Over the next two decades, scalable WASH interventions could avert 57,949–78,567 cholera cases, OCV could avert 38,569–77,636 cases, and interventions that combined WASH and OCV could avert 71,586–88,974 cases. Rate of implementation is the most influential variable, and combined approaches maximized the effect.

Population Vulnerability to Biannual Cholera Outbreaks and Associated Macro-Scale Drivers in the Bengal Delta

The highly populated floodplains of the Bengal Delta have a long history of endemic and epidemic cholera outbreaks, both coastal and inland. Previous studies have not addressed the spatio-temporal dynamics of population vulnerability related to the influence of underlying large-scale processes. We analyzed spatial and temporal variability of cholera incidence across six surveillance sites in the Bengal Delta and their association with regional hydroclimatic and environmental drivers. More specifically, we use salinity and flood inundation modeling across the vulnerable districts of Bangladesh to test earlier proposed hypotheses on the role of these environmental variables. Our results show strong influence of seasonal and interannual variability in estuarine salinity on spring outbreaks and inland flooding on fall outbreaks. A large segment of the population in the Bengal Delta floodplains remain vulnerable to these biannual cholera transmission mechanisms that provide ecologic and environmental conditions for outbreaks over large geographic regions.

Vaccines for the prevention of diarrhea due to cholera, shigella, ETEC and rotavirus

BackgroundDiarrhea is a leading cause of mortality in children under 5 years along with its long-term impact on growth and cognitive development. Despite advances in the understanding of diarrheal disorders and management strategies, globally nearly 750,000 children die annually as a consequence of diarrhea.MethodsWe conducted a systematic review of the efficacy and effectiveness studies. We used a standardized abstraction and grading format and performed meta-analyses for all outcomes. The estimated effect of cholera, shigella, Enterotoxigenic Escherichia coli (ETEC) and rotavirus vaccines was determined by applying the standard Child Health Epidemiology Reference Group (CHERG) rules.ResultsA total of 24 papers were selected and analyzed for all the four vaccines. Based on the evidence, we propose a 74% mortality reduction in rotavirus specific mortality, 52% reduction in cholera incidence due to their respective vaccines. We did not find sufficient evidence and a suitable outcome to project mortality reductions for cholera, ETEC and shigella in children under 5 years.ConclusionVaccines for rotavirus and cholera have the potential to reduce diarrhea morbidity and mortality burden. But there is no substantial evidence of efficacy for ETEC and shigella vaccines, although several promising vaccine concepts are moving from the development and testing pipeline towards efficacy and Phase 3 trials.

A water marker monitored by satellites to predict seasonal endemic cholera

The ability to predict an occurrence of cholera, a water-related disease, offers a significant public health advantage. Satellite-based estimates of chlorophyll, a surrogate for plankton abundance, have been linked to cholera incidence. However, cholera bacteria can survive under a variety of coastal ecological conditions, thus constraining the predictive ability of the chlorophyll, since it provides only an estimate of greenness of seawater. Here, a new remote-sensing-based index is proposed: Satellite Water Marker (SWM), which estimates the condition of coastal water, based on observed variability in the difference between blue (412 nm) and green (555 nm) wavelengths that can be related to seasonal cholera incidence. The index is bounded between physically separable wavelengths for relatively clear (blue) and turbid (green) water. Using SWM, prediction of cholera with reasonable accuracy, at least two months in advance, can potentially be achieved in the endemic coastal regions.

A framework for predicting endemic cholera using satellite derived environmental determinants

Cholera remains one of the most prevalent water-related infections in many tropical regions of the world. Macro-environmental processes provide a natural ecological niche for Vibrio cholerae and because powerful evidence of new biotypes is emerging, it is unlikely that the bacteria will be fully eradicated. Consequently, to develop effective intervention and mitigation strategies, it is necessary to develop cholera prediction models with several months' lead time. Almost all cholera outbreaks originate near the coastal areas and cholera bacteria exhibit a strong relationship with coastal plankton. Using chlorophyll as a surrogate for plankton bloom in coastal areas, recent studies have postulated a relationship between chlorophyll and cholera incidence. Here, we show that seasonal cholera outbreaks in the Bengal Delta can be predicted two to three months in advance with an overall prediction accuracy of over 75% by using satellite-derived chlorophyll and air temperature data. Such high prediction accuracy is achievable because the two seasonal peaks of cholera are predicted using two separate models representing distinctive macro-scale environmental processes. We have shown that interannual variability of pre-monsoon cholera outbreaks can be satisfactorily explained with coastal plankton blooms and a cascade of hydro-coastal processes. Post-monsoon cholera outbreaks, on the other hand, are related to macro-scale monsoon processes and subsequent breakdown of sanitary conditions. Our results demonstrate that satellite data over a range of space and time scales are effective in developing a cholera prediction model for the Bengal Delta with several months' lead time. We anticipate our modeling framework and findings will provide the impetus to explore the utility of satellite derived macro-scale variables for cholera prediction in other cholera endemic regions.

Time Series Analysis of Cholera in Matlab, Bangladesh, during 1988-2001

The study examined the impact of in-situ climatic and marine environmental variability on cholera incidence in an endemic area of Bangladesh and developed a forecasting model for understanding the magnitude of incidence. Diarrhoea surveillance data collected between 1988 and 2001 were obtained from a field research site in Matlab, Bangladesh. Cholera cases were defined as Vibrio cholerae O1 isolated from faecal specimens of patients who sought care at treatment centres serving the Matlab population. Cholera incidence for 168 months was correlated with remotely-sensed sea-surface temperature (SST) and in-situ environmental data, including rainfall and ambient temperature. A seasonal autoregressive integrated moving average (SARIMA) model was used for determining the impact of climatic and environmental variability on cholera incidence and evaluating the ability of the model to forecast the magnitude of cholera. There were 4,157 cholera cases during the study period, with an average of 1.4 cases per 1,000 people. Since monthly cholera cases varied significantly by month, it was necessary to stabilize the variance of cholera incidence by computing the natural logarithm to conduct the analysis. The SARIMA model shows temporal clustering of cholera at one- and 12-month lags. There was a 6% increase in cholera incidence with a minimum temperature increase of one degree celsius in the current month. For increase of SST by one degree celsius, there was a 25% increase in the cholera incidence at currrent month and 18% increase in the cholera incidence at two months. Rainfall did not influenc to cause variation in cholera incidence during the study period. The model forecast the fluctuation of cholera incidence in Matlab reasonably well (Root mean square error, RMSE: 0.108). Thus, the ambient and sea-surface temperature-based model could be used in forecasting cholera outbreaks in Matlab.

Reexamining El Niño and Cholera in Peru: A Climate Affairs Approach

Abstract In the 1990s Peru experienced the first cholera epidemic after almost a century. The source of emergence was initially attributed to a cargo ship, but later there was evidence of an El Niño association. It was hypothesized that marine ecosystem changes associated with El Niño led to the propagation of V. cholerae along the coast of Peru, which in turn initiated the onset of the epidemic in 1991. Earlier studies supported this explanation by demonstrating a relationship between elevated temperatures and increased cholera incidence in Peru; however, other aspects of El Niño–Southern Oscillation (ENSO) and their potential impacts on cholera were not investigated. Therefore, this study examines the relationship between El Niño and cholera in Peru from a holistic view of the ENSO cycle. A “climate affairs” approach is employed as a conceptual framework to incorporate ENSO’s multidimensional nature and to generate new hypotheses about the ENSO and cholera association in Peru. The findings reveal that ENSO may have been linked to the cholera epidemic through multiple pathways, including rainfall extremes, La Niña, and social vulnerability, with impacts depending on the geography of teleconnections within Peru. When the definition of an ENSO event is examined, cholera appears to have emerged either during ENSO neutral or La Niña conditions. Furthermore, the analysis herein suggests that the impact of El Niño arrived much later, possibly resulting in heightened transmission in the austral summer of 1992. In conclusion, a modified hypothesis with these new insights on cholera emergence and transmission in Peru is presented.

A Differential Effect of Indian Ocean Dipole and El Niño on Cholera Dynamics in Bangladesh

BackgroundA stationary (i.e., constant through time) association between El Niño Southern Oscillation (ENSO), the Indian Ocean Dipole (IOD) and epidemics of cholera in Bangladesh has been widely assumed. However, whether or not elements of the local climate that are relevant for cholera transmission have stationary signatures of the IOD on their dynamics over different time scales is still not clear. Here we report results on the time-varying relationships between the various remote and local environmental drivers and cholera incidence in Bangladesh.Methodology/Principal FindingsWe performed a cross wavelet coherency analysis to examine patterns of association between monthly cholera cases in the hospitals in Dhaka and Matlab (1983–2008) and indices for both IOD and ENSO. Our results showed that the strength of both the IOD and ENSO associations with cholera hospitalizations changed across time scales during the study period. In Dhaka, 4-year long coherent cycles were observed between cholera and the index of IOD in 1988–1997. In Matlab, the effect of ENSO was more dominant while there was no evidence for an IOD effect on cholera hospitalizations.Conclusions/SignificanceOur results call for the consideration of non-stationary, possibly non-linear, patterns of association between cholera hospitalizations and climatic factors in cholera epidemic early warning systems.

Characteristics of Diarrheal Illnesses in Non-Breast Fed Infants Attending a Large Urban Diarrheal Disease Hospital in Bangladesh

BackgroundLack of breast feeding is associated with higher morbidity and case-fatality from both bacterial and viral etiologic diarrheas. However, there is very limited data on the characteristics of non–breastfed infants attending hospital with diarrheal illnesses caused by common bacterial and viral pathogens. Our objective was to assess the impact of lack of breast feeding on diarrheal illnesses in infants living in urban Bangladesh.MethodsWe extracted data of infants (0–11 months) for analyses from the data archive of Diarrheal Disease Surveillance System (DDSS) of the Dhaka Hospital of icddr,b for the period 2008–2011.ResultsThe prevalence of breastfeeding in infants attending the hospital with diarrhea reduced from 31% in 2008 to 17% in 2011, with corresponding increase in the prevalence of non-breastfed (chi square for trend <0.001). Among breastfed infants, the incidence of rotavirus infections was higher (43%) among the 0–5 months age group than infants aged 9–11 months (18%). On the other hand, among non-breastfed infants, the incidence of rotavirus infections was much higher (82%) among 9–11 months old infants compared to those in 0–5 months age group (57%) (chi square for trend <0.001). Very similar trends were also observed in the incidence of cholera and ETEC diarrheas among different age groups of breastfed and non-breastfed infants (chi square for trend 0.020 and 0.001 respectively). However, for shigellosis, the statistical difference remained unchanged among both the groups (chi square for trend 0.240).Conclusion and SignificanceWe observed protective role of breastfeeding in infantile diarrhea caused by the major viral and common bacterial agents. These findings underscore the importance of promotion and expansion of breastfeeding campaigns in Bangladesh and elsewhere.

Herd Protection by a Bivalent Killed Whole-Cell Oral Cholera Vaccine in the Slums of Kolkata, India

We evaluated the herd protection conferred by an oral cholera vaccine using 2 approaches: cluster design and geographic information system (GIS) design. Residents living in 3933 dwellings (clusters) in Kolkata, India, were cluster-randomized to receive either cholera vaccine or oral placebo. Nonpregnant residents aged≥1 year were invited to participate in the trial. Only the first episode of cholera detected for a subject between 14 and 1095 days after a second dose was considered. In the cluster design, indirect protection was assessed by comparing the incidence of cholera among nonparticipants in vaccine clusters vs those in placebo clusters. In the GIS analysis, herd protection was assessed by evaluating association between vaccine coverage among the population residing within 250 m of the household and the occurrence of cholera in that population. Among 107 347 eligible residents, 66 990 received 2 doses of either cholera vaccine or placebo. In the cluster design, the 3-year data showed significant total protection (66% protection, 95% confidence interval [CI], 50%-78%, P<.01) but no evidence of indirect protection. With the GIS approach, the risk of cholera among placebo recipients was inversely related to neighborhood-level vaccine coverage, and the trend was highly significant (P<.01). This relationship held in multivariable models that also controlled for potentially confounding demographic variables (hazard ratio, 0.94 [95% CI, .90-.98]; P<.01). Indirect protection was evident in analyses using the GIS approach but not the cluster design approach, likely owing to considerable transmission of cholera between clusters, which would vitiate herd protection in the cluster analyses. NCT00289224.

Cholera, Shigellosis and Salmonellosis Incidence Among the People of some Districts of Nepal

Diarrhoea is a major health problem throughout the world, and responsible for high morbidity and mortality in Nepal. The cross-sectional prospective study was carried out to determine the incidence of Cholera, Shigellosis and Salmonellosis with screening of possible extended spectrum â-lactamase producers from 268 diarrhoeal stool samples from Nepalgunj area and different hospitals of Nepal during April 2010 to January 2011. The specimens were processed by standard microbiological methods and the casual organisms confirmed with serology. Altogether 14.18% of bacterial incidence was found with 8.21% incidence of Vibrio cholerae O1, 2.24% of Shigella spp. and 3.73% of Salmonella spp. All isolated Vibrio cholerae O1 were El Tor Ogawa and all Shigella spp. were Shigella flexneri B. Highest bacterial culture positivity (47.36%) were observed in Kathmandu while highest V. cholerae isolation (77.27%) was observed in Nepalgunj. The highest number of Salmonella spp. and Shigella spp. were isolated from Kanti Children’s Hospital. Highest bacterial culture positivity (47.36%) and highest isolation of V. cholerae (81.81%) were observed in August. The bacterial culture positivity was significantly associated with places and months (p &lt;0.05). However, there was no statistical difference in the bacterial culture positivity with sex (P &gt;0.05). 100% Vibrio cholerae, 100% Shigella spp. and 80% Salmonella spp. were multi-drug resistant. Only one Salmonella Cholerasuis was extended spectrum â-lactamase producer. Nepal Journal of Science and Technology Vol. 13, No. 1 (2012) 165-172 DOI: http://dx.doi.org/10.3126/njst.v13i1.7455