Diarrheal Outbreaks Research Articles

Cholera outbreak investigation report in Mille woreda, Afar region, Ethiopia, 2019

Introduction: Cholera has remained as one of the important public health problems in Asia and Africa causing substantial morbidity and mortality. Although the burden is greatest in low-income populations with poor access to safe water, and sanitation, cholera is also an important health problem globally. Cholera occurs both as a short outbreak and protracted epidemic/pandemic and when uncontrolled; is devastating to communities and to their prospects for development. To respond quickly and control the outbreak, investigation is crucial; identify risk factors that cause the outbreak, and suggest prevention and control measures. Objective: To identify risk factors and etiology of diarrheal disease outbreak and suggest prevention and control measures in Mille woreda, Afar region Ethiopia, May- June, 2018. Method: Descriptive followed by unmatched case-control study with 1:2 ratio were conducted from May-June 2018. A total of 68 patients and 136 controls were enrolled. A structured interviewer-administered questionnaire was used and medical records and line lists review. Simple random sampling was used to select controls and the first 68 cases. Data were analyzed by SPSS and presented using odd ratio, and tables. Environmental and patient samples were collected for culture and rapid diagnostic test. Result: The investigation identified 229 cholera patients, including 22 rapid diagnostic test confirmed patients and seven culture confirmed patients (attack rate: 8.31%, 229/27,562). Index patient were imported from epi-linked woreda. Diglena geraro kebele were the Epicenter of the outbreak. Epicure trend shows common source infection. Using bifurcation of Awash River for drinking, use untreated/ uncoiled water, poor hand washing practices, and close contact with cholera sick person were found to be associated with cholera. Conclusion: This outbreak was caused by vibrio cholera 01 secondary to drinking water from a bifurcation of Awash River and using untreated water. Contact with diseased person, and use untreated/ uncoiled water was associated with being patients. In order to reduce the risk of cholera, safe drinking water or water treatment chemicals needs to be provided to communities.

Facilitating hand hygiene in displacement camps during the COVID-19 pandemic: a qualitative assessment of a novel handwashing stand and hygiene promotion package

BackgroundHandwashing with soap is critical for the prevention of diarrhoeal diseases and outbreak related diseases, including interrupting the transmission of COVID-19. People living in large displacement settings are particularly vulnerable to such outbreaks, however, practicing handwashing is typically challenging in these contexts.MethodsWe conducted a qualitative assessment of the implementation of a combined intervention to facilitate handwashing behaviour in displacement camps and in surrounding communities in Bangladesh, Ethiopia and the Democratic Republic of Congo during the COVID-19 pandemic. The intervention comprised a ‘hardware’ infrastructural component (provision of the Oxfam Handwashing Station) and a ‘software’ hygiene promotion package (Mum’s Magic Hands). We used programmatic logbooks, interviews with implementation staff and focus group discussions with crisis-affected populations to assess the use, feasibility and acceptability of the intervention.ResultsBoth components of the intervention were viewed as novel and appealing by implementing staff and crisis-affected populations across the study sites. The acceptability of the handwashing station could be improved by redesigning the tap and legs, exploring local supply chain options, and by providing a greater number of facilities. The implementation of the hygiene promotion package varied substantially by country making it challenging to evaluate and compare. A greater focus on community engagement could address misconceptions, barriers related to the intuitiveness of the handwashing station design, and willingness to participate in the hygiene promotion component.ConclusionsThe combination of a ‘hardware’ and ‘software’ intervention in these settings appeared to facilitate both access and use of handwashing facilities. The acceptability of the combined intervention was partially because a great deal of effort had been put into their design. However, even when delivering well-designed interventions, there are many contextual aspects that need to be considered, as well as unintended consequences which can affect the acceptability of an intervention.

Development of a Molecular Marker Based on the Mitochondrial Genome for Detection of Cyclospora cayetanensis in Food and Water Samples.

Cyclospora cayetanensis is a coccidian parasite that causes diarrheal illness outbreaks worldwide. The development of new laboratory methods for detection of C. cayetanensis is of critical importance because of the high potential for environmental samples to be contaminated with a myriad of microorganisms, adversely impacting the specificity when testing samples from various sources using a single molecular assay. In this study, a new sequencing-based method was designed targeting a specific fragment of C. cayetanensis cytochrome oxidase gene and developed as a complementary method to the TaqMan qPCR present in the U.S. FDA BAM Chapter 19b and Chapter 19c. The comparative results between the new PCR protocol and the qPCR for detection of C. cayetanensis in food and water samples provided similar results in both matrices with the same seeding level. The target region and primers in the protocol discussed in this study contain sufficient Cyclospora-specific sequence fidelity as observed by sequence comparison with other Eimeriidae species. The sequence of the PCR product appears to represent a robust target for identifying C. cayetanensis on samples from different sources. Such a sensitive method for detection of C. cayetanensis would add to the target repertoire of qPCR-based screening strategies for food and water samples.

Multiple reassortment and interspecies transmission events contribute to the diversity of porcine-like human rotavirus C strains detected in South Korea.

Globally, rotavirus C (RVC) causes diarrhoeal outbreaks, mainly in swine, with sporadic incidents in human, bovine, and canine populations. In this study, two human RVC strains, RVC/Human-wt/KOR/CAU13-1-77/2013 and RVC/Human-wt/KOR/CAU14-1-242/2014, were isolated in South Korea, and their complete genome sequences were compared with those of other human- and animal-origin RVC strains found worldwide. Genetic analysis revealed that these viruses have a G4-P[2]-I2-R2-C2-M3-A2-N2-T2-E2-H2 genotype constellation. Phylogenetic analysis indicated that these Korean RVC strains belong to the M3 lineage of the VP3 gene in human RVC from Japan and China and porcine RVC from Japan. These results suggest that RVC circulates in northeast Asia in both the human and porcine populations. These results also provide evidence of interspecies RVC reassortment events.

Novel fold of rotavirus glycan-binding domain predicted by AlphaFold2 and determined by X-ray crystallography.

The VP8* domain of spike protein VP4 in group A and C rotaviruses, which cause epidemic gastroenteritis in children, exhibits a conserved galectin-like fold for recognizing glycans during cell entry. In group B rotavirus, which causes significant diarrheal outbreaks in adults, the VP8* domain (VP8*B) surprisingly lacks sequence similarity with VP8* of group A or group C rotavirus. Here, by using the recently developed AlphaFold2 for ab initio structure prediction and validating the predicted model by determining a 1.3-Å crystal structure, we show that VP8*B exhibits a novel fold distinct from the galectin fold. This fold with a β-sheet clasping an α-helix represents a new fold for glycan recognition based on glycan array screening, which shows that VP8*B recognizes glycans containing N-acetyllactosamine moiety. Although uncommon, our study illustrates how evolution can incorporate structurally distinct folds with similar functionality in a homologous protein within the same virus genus.

Epidemiological Investigation of an Outbreak of Acute Diarrheal Disease at Talegaon Dabhade, Mawal Block, Pune, Maharashtra

Background: Acute Diarrheal Disease (ADD) affects millions of people across the globe, especially in poor socio-economic regions. Most of the diseases and deaths among children result from diarrhea resulting from contaminated water and food sources. In India, most diarrheal outbreaks can be attributed to contaminated water.These outbreaks can be prevented through the provision of safe drinking water. Outbreak investigation plays a vital role in ascertaining the causes of an outbreak and thereby keeping a check on communicable diseases. This paper explores the investigation that followed an outbreak of diarrhea in one of the interior regions of the Pune district in Maharashtra. Objectives: (i) To confirm the existence of an outbreak at Talegaon Dabhade (ii) To identify the source of infection and mode of transmission (iii) To control and prevent the further spread of the outbreak. Methods: A ground review of the outbreak situation was done along with the local health authority of Talegaon Dabhade and the Primary Health Centre (PHC) Staff. Information regarding water samples collection and testing was obtained from Talegaon Municipal Council officials. An observational cross-sectional study using a mixed-method approach was conducted. Face-to-face interviews of 8 cases were conducted using a semi-structured interview schedule. Result: The frontline workers identified a total of 624 cases during the survey. About 209 patients came to seek treatment at the PHC Outpatient Department (OPD) with three reported hospitalizations. The field workers started reporting cases on 27th December 2021. A total of 217 water samples collected from multiple points were sent for water quality testing. Only one sample from the house of an infected person came out to be positive for coliforms. The source of infection of the outbreak could not be identified. Conclusion: Outbreaks can be prevented through training of local health staff, strengthening labs at the government health facilities, and enhancing Information, Education and Communication (IEC) activities. This ensures early identification andtimely response to epidemic-prone diseases.

Evaluation of a New Norovirus Genogroups GI and GII In Vitro Molecular Diagnostic Assay Using Clinical Specimens Collected from Acute Diarrheal Outbreaks.

Norovirus is a leading cause of acute gastroenteritis (AGE) in Taiwan. To improve diagnosis as part of laboratory surveillance, AGE surveillance was conducted using a new fluorescent probe hydrolysis-based insulated isothermal polymerase chain reaction (PCR) method, the POCKIT system, and the results were compared with those obtained from conventional methods. A total of 119 clinical stool samples from reported AGE outbreaks were collected for this study. From 83 real-time reverse transcription PCR (rRT-PCR) norovirus-positive cases, the POCKIT system identified 78 with a sensitivity of 90.3% in GI genogroup and 96.7% in GII genogroup. The specificity for both GI and GII genogroups was 100%. Overall, the POCKIT system is faster and easier to use than the conventional rRT-PCR method, and because of its high sensitivity and specificity, this system is a promising alternative for the detection of norovirus in patients with AGE, and would benefit public health laboratories for near real-time surveillance of AGE epidemic outbreaks.

Intestinal Giardiasis in Children Undergoing Upper Endoscopy for Unexplained Gastrointestinal Symptoms: Implication for Diagnosis

Background Giardia lamblia is a flagellated protozoan causing diarrheal outbreaks worldwide. Microscopic stool examination is widely used. We conducted this study to explore intestinal giardiasis in children undergoing upper endoscopy for unexplained gastrointestinal symptoms. Methods The study included 160 children undergoing upper endoscopy for unexplained gastrointestinal symptoms (patients) and 90 children as controls. We collected stool samples for microscopic examination and ELISA coproantigen detection from all participants. We examined duodenal biopsies for patients. Results In patients, stool examination revealed Giardia in 23.8% and coproantigen detection was positive in 37.5%. Endoscopic duodenal biopsies revealed Giardia trophozoites in 5% of patients, in addition to various pathological changes. Conclusion Giardiasis was significantly higher (P = 0.001) in children with unexplained gastrointestinal complaints than the controls. Diagnosis by coproantigen detection was superior to microscopic stool examination, with a sensitivity of 90.9%. Duodenal biopsies examination confirmed the infection in fewer cases but added other diagnostic information.

An assessment on the effectiveness of the sanitary seal in protecting boreholes from contamination: A case of Mbare Suburb, Harare

Zimbabwe is projected to suffer water stress by 2025. Water availability is decreasing in the capital Harare, particularly in high density settlements where people rely mainly on boreholes. Anthropogenic pollution and poorly constructed boreholes lead to high levels of bacteriological contamination of borehole water sources, posing an increased risk of diarrheal disease for beneficiaries. To mitigate the risk of recurrent diarrheal outbreaks, Médecins Sans Frontiers piloted the incorporation of borehole sanitary seal in accordance with the local geology while drilling new boreholes in Harare. This study compared physical, chemical and bacteriological parameters between boreholes with two different sanitary seal types and no sanitary seal in Harare's Mbare suburb. 14 boreholes were classified into three categories based on the installed sanitary seal. Water quality analysis were conducted to describe physical, chemical and bacteriological parameters across three categories. The three categories included 4 boreholes with no seal, 6 with 3–6 m seal (random seal) and 4 with 18–25 m seal (proper seal; done in accordance with local geology). Water samples were collected between February 2019 to January 2020 in 3 sampling periods and analysed according to APHA standards. Groundwater vulnerability assessment to map pollution risk of the study areas showed 80% of the study area had high vulnerability. Results of water quality analysis revealed that only boreholes with 18–25m sanitary seal satisfied the WHO guidelines for drinking water. This study suggests that local geology should be considered to install borehole sanitary seals for contaminated shallow water aquifers in urban settlements.

Molecular characterization of Vibrio cholerae O1 isolates obtained from outbreaks in the Philippines, 2015-2016.

Introduction. The Philippines, comprising three island groups, namely, Luzon, Visayas and Mindanao, experienced an increase in cholera outbreaks in 2016. Previous studies have shown that Vibrio cholerae isolates obtained from the Philippines are novel hybrid El Tor strains that have evolved in the country and are clearly distinct from those found in Mozambique and Cameroon.Gap statement. The characterization of the strains isolated from outbreaks has been limited to phenotypic characteristics, such as biochemical and serological characteristics, in most previous studies.Aim. We performed multilocus variable-number tandem repeat (VNTR) analysis (MLVA) for V. cholerae isolates obtained from 2015 to 2016 to further characterize and understand the emergence and dissemination of the strains in the Philippines.Methodology. A total of 139 V. cholerae O1 Ogawa biotype El Tor isolates were obtained from the Philippines during diarrhoeal outbreaks in 18 provinces between 2015 and 2016. VNTR data were analysed to classify the MLVA profiles where the large-chromosome types (LCTs) were applied for grouping.Results. We identified 50 MLVA types among 139 isolates originating from 18 provinces, and 14 LCTs. The distribution of the LCTs was variable, and a few were located in specific areas or even in specific provinces. Based on eBURST analysis, 99 isolates with 7 LCTs and 32 MLVA types belonged to 1 group, suggesting that they were related to each other. LCT A was predominant (n=67) and was isolated from Luzon and Visayas. LCT A had 14 MLVA types; however, it mostly emerged during a single quarter of a year. Eight clusters were identified, each of which involved specific MLVA type(s). The largest cluster involved 23 isolates showing 3 MLVA types, 21 of which were MLVA type A-14 isolated from Negros Occidental during quarter 4 of 2016. Comparative analysis showed that almost all isolates from the Philippines were distinct from those in other countries.Conclusions. The genotypic relationship of the V. cholerae isolates obtained during outbreaks in the Philippines was studied, and their emergence and dissemination were elucidated. MLVA revealed the short-term dynamics of V. cholerae genotypes in the Philippines.

New Insights into the Potential Cytotoxic Role of Bacillus cytotoxicus Cytotoxin K-1.

The thermotolerant representative of the Bacillus cereus group, Bacillus cytotoxicus, reliably harbors the coding gene of cytotoxin K-1 (CytK-1). This protein is a highly cytotoxic variant of CytK toxin, initially recovered from a diarrheal foodborne outbreak that caused the death of three people. In recent years, the cytotoxicity of B. cytotoxicus has become controversial, with some strains displaying a high cytotoxicity while others show no cytotoxicity towards cell lines. In order to better circumscribe the potential pathogenic role of CytK-1, knockout (KO) mutants were constructed in two B. cytotoxicus strains, E8.1 and E28.3. The complementation of the cytK-1 KO mutation was implemented in a mutant strain lacking in the cytK-1 gene. Using the tetrazolium salt (MTT) method, cytotoxicity tests of the cytK-1 KO and complemented mutants, as well as those of their wild-type strains, were carried out on Caco-2 cells. The results showed that cytK-1 KO mutants were significantly less cytotoxic than the parental wild-type strains. However, the complemented mutant was as cytotoxic as the wild-type, suggesting that CytK-1 is the major cytotoxicity factor in B. cytotoxicus.

High-throughput low-cost nl-qPCR for enteropathogen detection: A proof-of-concept among hospitalized patients in Bangladesh.

BackgroundDiarrheal disease is a leading cause of morbidity and mortality globally, especially in low- and middle-income countries. High-throughput and low-cost approaches to identify etiologic agents are needed to guide public health mitigation. Nanoliter-qPCR (nl-qPCR) is an attractive alternative to more expensive methods yet is nascent in application and without a proof-of-concept among hospitalized patients.MethodsA census-based study was conducted among diarrheal patients admitted at two government hospitals in rural Bangladesh during a diarrheal outbreak period. DNA was extracted from stool samples and assayed by nl-qPCR for common bacterial, protozoan, and helminth enteropathogens as the primary outcome.ResultsA total of 961 patients were enrolled; stool samples were collected from 827 patients. Enteropathogens were detected in 69% of patient samples; More than one enteropathogen was detected in 32%. Enteropathogens most commonly detected were enteroaggregative Escherichia coli (26.0%), Shiga toxin-producing E.coli (18.3%), enterotoxigenic E. coli (15.5% heat stable toxin positive, 2.2% heat labile toxin positive), Shigella spp. (14.8%), and Vibrio cholerae (9.0%). Geospatial analysis revealed that the median number of pathogens per patient and the proportion of cases presenting with severe dehydration were greatest amongst patients residing closest to the study hospitals.”ConclusionsThis study demonstrates a proof-of-concept for nl-qPCR as a high-throughput low-cost method for enteropathogen detection among hospitalized patients.

Morphological, biological, and genomic characterization of a newly isolated lytic phage Sfk20 infecting Shigella flexneri, Shigella sonnei, and Shigella dysenteriae1

Shigellosis, caused by Shigella bacterial spp., is one of the leading causes of diarrheal morbidity and mortality. An increasing prevalence of multidrug-resistant Shigella species has revived the importance of bacteriophages as an alternative therapy to antibiotics. In this study, a novel bacteriophage, Sfk20, has been isolated from water bodies of a diarrheal outbreak area in Kolkata (India) with lytic activity against many Shigella spp. Phage Sfk20 showed a latent period of 20 min and a large burst size of 123 pfu per infected cell in a one-step growth analysis. Phage-host interaction and lytic activity confirmed by phage attachment, intracellular phage development, and bacterial cell burst using ultrathin sectioning and TEM analysis. The genomic analysis revealed that the double-stranded DNA genome of Sfk20 contains 164,878 bp with 35.62% G + C content and 241 ORFs. Results suggested phage Sfk20 to include as a member of the T4 myoviridae bacteriophage group. Phage Sfk20 has shown anti-biofilm potential against Shigella species. The results of this study imply that Sfk20 has good possibilities to be used as a biocontrol agent.

Identification of a hybrid atypical enteropathogenic and enteroaggregative Escherichia coli (aEPEC/EAEC) clone of serotype O3:H2 associated with a diarrheal outbreak in Brazil.

Enteropathogenic (EPEC) and enteroaggregative (EAEC) Escherichia coli are two of the major pathotypes of diarrheagenic E. coli causing disease worldwide. Here, we report a diarrheal outbreak caused by E. coli of serotype O3:H2, harboring virulence markers from EPEC (eae) and/or EAEC (aggR). This is likely the first E. coli diarrheal outbreak caused by a hybrid atypical-EPEC/EAEC clone reported in Brazil.

Environmental Drivers of the Seasonal Prevalence of Enteropathogenic Bacteria in the Gulf Ecosystem of Gujarat, India: Unravelling Its Diarrheal Enigma

Recurrent episodes of water borne diarrheal outbreaks is the pressing public health crisis in the Gulf of Khambat (GoK), Gujarat and its adjoining area. We aimed to identify seasonality of environmental signatures associated with the dynamics of Gulf enteropathogens and related health implications. A yearlong sampling data has been generated from the five sites across the GoK of high anthropogenic burden and contrasting hydrological settings. Hydro-chemical characteristics of water samples and bacteriological indices were analysed on field and laboratory condition respectively and robust statistics was applied to assess their interrelationship and associated health risks. Annual variation of hydro-chemical indices viz. temperature 26.4oC–36.7oC, pH 7.51–8.44, salinity 28.3–36.7 mS/cm, turbidity 3.6–995 NTU and Dissolved Oxygen (DO) was recorded in the water samples. Extremely high turbidity (70.5-995) along with high salinity (28.3-34.8) is found to be the unique characteristic feature of Gulf water, which facilitates the abundance of various enteropathogenic bacterial species, specially the clinically important ones like V. cholerae, V. alginolyticus and E. coli. Surprisingly, an explosive annual preponderance of V. alginolyticus could be observed throughout all the study sites and existence of V. cholerae is restricted only in the high turbid water (>500NTU) of Gulf. Detection of E. coli is also a significant report from this high saline habitat, indicating faecal contamination. Seasonality of Vibrios and coliforms are highly influenced by precipitation rate and turbidity of water (p<0.05). DO level is found to be another crucial marker which regulates distribution of enteropathogens across the Gulf water as well as indicates the pollution level of Gulf attributed to environmental health risk. This is the first report of a longitudinal study of enteropathogenic load in GoK and its direct relationship with diarrheal incidence profile, which adds valuable knowledge for the formulation of ‘bio-environmental tool’ for effective water quality monitoring and disease prevention.

Genotyping of Cryptosporidium Parvum by PCR-Sequencing Analysis for The 70 Heat Shock Protein (HSP70) Gene and Dihydrofolate Reductase (DHFR) Gene

Cryptosporidium is an apicomplexan parasite that is increasingly recognized among immunocompetent hostsas a leading cause of childhood diarrhea in lower source settings and of waterborne diarrheal outbreaks inhigh income countries. C. parvum, which infects bovines, wild animals and humans, account for the majorityof human infections. Cryptosporidium oocysts are transmitted via the fecal oral route, including by person toperson spread, from contaminated food or water, or from contact with infected animals. 300 Stool sampleswere collected from patients in Hilla city from different hospitals. DNA extracted from stool samples, PCRamplification of DNA. Genotyping of HSP70 gene and DHFR Gene was performed using a polymerasechain reaction technique, followed by DNA sequencing. Accordingly, these DNA polymorphisms wereconfirmed using DNA sequencing. The sequencing results showed the presence of many SNPs determinedin the HSP70 gene and DHFR gene.

Haitian variant Vibrio cholerae O1 Ogawa caused cholera outbreaks in Odisha

PurposeDiarrheal disorders particularly cholera cause a significant threat resulting in high morbidity and mortality in the coastal and tribal areas of Odisha. Two sequential diarrheal outbreaks reported in 2016 from Balasore and Rayagada districts of Odisha were investigated to find out the causative organisms, antibiogram profile and molecular analysis of the isolated pathogens. MethodBacteriological analysis and antibiogram profiles of the pathogens were carried out as per the standard procedure followed. The double mismatch amplification mutation (DMAMA) PCR for ctxB gene, sequencing and pulse-field gel electrophoresis (PFGE) were carried out on Vibrio cholerae O1 strains. ResultsThe rectal swabs and water samples from these districts were positive for V. cholerae O1 Ogawa biotype El Tor. The V. cholerae O1 strains isolated from Balasore district were multidrug resistant to many antibiotics which differed from the isolates of Rayagada district. The DMAMA PCR assay on all clinical and water isolates from these areas and some strains from other districts exhibited ctxB7 allele of V. cholerae O1 which correlates with the sequencing results having different pulsotypes. The Haitian variant of V. cholerae O1 strains which were compared with the V. cholerae O1 strains of 1999 and 2000 exhibited different pulsotypes. ConclusionThe present study reports cholera outbreaks due to multidrug resistant ctxB7 allele of V. cholerae O1 from both coastal (Balasore) and tribal (Rayagada) areas of Odisha.

Microbiological status of drinking water sources and its relationship with human health in Solan, India.

In Solan district, the developmental activities associated with chemical based farming, rapid urbanization, and rampant industrialization have led to many diarrhoeal, gastroenteritis, and hepatitis disease outbreaks. This has necessitated for microbiological assessment of indicator organisms, the thermotolerant coliforms, in drinking water sources, and their relationship with diarrhoeal disease. All the 49 Public Health Institutes (PHIs) of the district were categorized into very low, low, moderate, and high disease burden regions by stratification method. For drinking water, 55.5, 16.5, and 17% people preferred springs, borewells, and hand-pump respectively. These sources inventoried by Knowledge, Attitude, and Practice survey in one of very low and seven of high disease burden regions, and were analyzed by multiple tube fermentation technique. A cross-sectional survey of 200 children was undertaken for diarrhoeal disease estimation. Parwanoo, an industrial and Kurgal, a non industrial region witnessed highest (30.20) and lowest (4.40) Most Probable Number (MPN) per 100 ml water of thermotolerant coliforms, respectively. Thermotolerant coliforms were also observed significantly more (16.77 MPN/100 ml water) in monsoon than in post monsoon season (9.04 MPN per 100 ml water). The thermotolerant coliform Escherichia coli was recovered from six and three water sources respectively during monsoon and post monsoon. A strong correlation (r = 0.78) existed between the diarrhoeal disease occurrence and the concentration of thermotolerant coliforms in monsoon whereas it was moderate (r = 0.61) in post monsoon. The study indicated more contamination of water sources due to industrial activities which further got aggravated during the rainy season of the region.

Acute diarrheal disease outbreak in Muzaffarpur Village, Chandauli District, Uttar Pradesh, India.

Acute diarrheal disease (ADD) outbreaks frequently occur in the Gangetic plains of Uttar Pradesh, India. In August 2017, Muzaffarpur village, Uttar Pradesh, reported an ADD outbreak. Outbreak investigation was conducted to find out the epidemiology and to identify the risk factors. A 1:1 area-matched case-control study was conducted. Suspected ADD case was defined as ≥3 loose stools or vomiting within 24 h in a Muzaffarpur resident between August 7 and September 9, 2017. A control was defined as an absence of loose stools and vomiting in a resident between August 7 and September 9, 2017. A matched odds ratio (mOR) with 95% confidence intervals (CIs) was calculated. Drinking water was assessed to test for the presence of any contamination. Stool specimens were tested for Vibrio cholerae, and water samples were also tested for any fecal contamination and residual chlorine. Among 70 cases (female = 60%; median age = 12 years, range = 3 months-70 years), two cases died and 35 cases were hospitalized. Area-A in Muzaffarpur had the highest attack rate (8%). The index case washed soiled clothes at well - A1 1 week before other cases occurred. Among 67 case-control pairs, water consumption from well-A1 (mOR: 43.00; 95% CI: 2.60-709.88) and not washing hands with soap (mOR: 2.87; 95% CI: 1.28-6.42) were associated with illness. All seven stool specimens tested negative for V. cholerae. All six water samples, including one from well-A1, tested positive for fecal contamination with <0.2 ppm of residual chlorine. This outbreak was associated with consumption of contaminated well water and hand hygiene. We recommended safe water provision, covering wells, handwashing with soap, access to toilets, and improved laboratory capacity for testing diarrheal pathogens.

Spread of Haitian Variant Vibrio cholerae O1 Causing Cholera Outbreaks in Odisha, India.

Cholera posed a significant threat causing outbreaks/epidemics with high morbidity and mortality in Odisha. This study envisages the characterisation of isolated pathogen from two cholera outbreaks reported in 2018 and 2019 from Bargarh and Rayagada districts of Odisha respectively. Vibrio cholerae O1 were isolated following standard techniques. The different virulent and drug resistant genes were detected by multiplex PCR assays; whereas the ctxB genotypes were characterised through double mismatch amplification mutation (DMAMA) PCR assay. The ctxB genes were further sequenced and pulse-field gel electrophoresis (PFGE) was done on some selected strains. The clinical and water isolates of Haitian variant (HCT) V. cholerae O1 Ogawa biotype El Tor with multi drug resistant strains were isolated from both the places. All the V. cholerae O1 strains were positive for virulence genes. The antibiotic resistant genes like dfrA1 (100%), strB (76.9%), intSXT (61.5%) were detected. The PFGE results on V. cholerae O1 strains exhibited two different pulsotypes. These cholera outbreaks were due to multidrug resistant HCT variant V. cholerae O1 strains which were circulating and caused the cholera outbreaks in Odisha. So continuous surveillance on diarrheal disorders is highly essential to prevent the future diarrheal outbreaks in this region.