Reduced Diarrhea Prevalence and Improvements in Handwashing with Soap and Stored Drinking Water Quality Associated with Diarrheal Disease Awareness Measured by Interactive Voice Response Messages in the CHoBI7 Mobile Health Program.

The Cholera-Hospital-Based-Intervention-for-7-Days (CHoBI7) mobile health program promotes water, sanitation, and hygiene (WASH) behaviors through interactive voice response (IVR), voice, and text messages to reduce diarrheal diseases in Bangladesh. The objective of this study was to investigate the relationship between responses to CHoBI7 WASH IVR quiz messages and subsequent diarrhea and WASH behaviors. Fourteen CHoBI7 IVR quiz messages on handwashing with soap and treatment of stored water were sent to 517 households with 1,777 participants during the 12-month program period. IVR message responses were classified as correct answer, incorrect answer, no response (did not press 1 or 2), and failed (did not answer the phone). Diarrhea prevalence was assessed through self-reported monthly clinical surveillance visits. Handwashing with soap was assessed by a 5-hour structured observation, and stored water quality was defined by Escherichia coli concentration. Households that responded correctly to a CHoBI7 IVR quiz message had significantly lower odds of diarrhea for all age groups (adults and children) at the subsequent visit 1 month later (odds ratio [OR], 0.73; 95% CI, 0.54-0.98), and significantly greater odds of handwashing with soap after stool-related events (OR, 2.48; 95% CI, 1.12-5.49) and E. coli levels < 100 colony forming units (CFU)/100 mL (World Health Organization high-risk cutoff) in the stored household water (OR, 2.04; 95% CI, 1.25-3.33) compared with households that did not answer CHoBI7 IVR quiz calls. Correct responses to CHoBI7 IVR quizzes were associated with decreased diarrhea prevalence and improved stored drinking water quality and handwashing with soap behaviors at the subsequent visits. These findings suggest engagement in the CHoBI7 mobile health (mHealth) program and awareness of diarrheal disease prevention can reduce diarrhea and facilitate changes in WASH behaviors.

Food Hygiene and Fecal Contamination on the Household Compound are Associated with Increased Pediatric Diarrhea in Urban Bangladesh (CHoBI7 Program).

In this prospective cohort study, we explored individual- and household-level risk factors associated with diarrheal diseases among 251 children younger than 5 years in slum areas of urban Dhaka, Bangladesh. During the 3-month study period, diarrhea surveillance was conducted monthly, and spot checks of the household compound were performed at baseline to assess the presence of feces (animal or human) in the household compound and in cooking and food storage areas, and to assess whether cooked food was covered and refrigerated. We also collected caregiver reports on child mouthing behaviors. Children living in households with feces within 10 steps of cooking and food storage areas (odds ratio [OR], 8.43; 95% CI, 1.01-70.18), those with visible feces found on the ground of the household compound (OR, 4.05; 95% CI, 1.24-13.22), and those in households found to keep cooked food uncovered and without refrigeration (OR, 6.16; 95% CI, 1.11-34.25) during spot checks had a significantly greater odds of diarrhea. There was no significant association between pediatric diarrhea and caregiver-reported child mouthing behaviors or presence of animals in the cooking area. These study findings demonstrate that presence of visible feces in the household compound and near cooking and food storage areas, and poor household food hygiene practices, were significant risk factors for diarrheal disease among young children in Dhaka, Bangladesh. Health communication programs are needed to target these exposure pathways to fecal pathogens.

Randomized Controlled Trial of the Cholera-Hospital-Based-Intervention-for-7-Days (CHoBI7) Cholera Rapid Response Program to Reduce Diarrheal Diseases in Bangladesh.

(a) Objective: To build an evidence base on effective water, sanitation, and hygiene interventions to reduce diarrheal diseases in cholera hotspots, we developed the CHoBI7 Cholera Rapid Response Program. (b) Methods: Once a cholera patient (confirmed by bacterial culture) is identified at a health facility, a health promoter delivers a targeted WASH intervention to the cholera hotspot (households within 20 m of a cholera patient) through both in-person visits during the first week and bi-weekly WASH mobile messages for the 3-month program period. A randomized controlled trial of the CHoBI7 Cholera Rapid Response Program was conducted with 284 participants in 15 cholera hotspots around cholera patients in urban Dhaka, Bangladesh. This program was compared to the standard message in Bangladesh on the use of oral rehydration solution for dehydration. Five-hour structured observation of handwashing with soap and diarrhea surveillance was conducted monthly. (c) Findings: Handwashing with soap at food- and stool-related events was significantly higher in the CHoBI7 Cholera Rapid Response Program arm compared to the standard message arm at all timepoints (overall 54% in the CHoBI7 arm vs. 23% in the standard arm, p < 0.05). Furthermore, there was a significant reduction in diarrheal prevalence for all participants (adults and children) (Prevalence Ratio (PR) 0.35, 95% CI: 0.14-0.85) and for children under 5 years of age (PR: 0.27, 95% CI: 0.085-0.87) during the 3-month program. (d) Conclusions: These findings demonstrate that the CHoBI7 Cholera Rapid Response Program is effective in lowering diarrhea prevalence and increasing handwashing with soap for a population at high risk of cholera.

Formative Research for the Development of the CHoBI7 Cholera Rapid Response Program for Cholera Hotspots in Bangladesh.

Cholera is a severe form of acute watery diarrhea that if left untreated can result in death. Globally, there are 2.9 million cholera cases annually. Individuals living in close proximity to cholera cases are at a higher risk for developing cholera compared to the general population. Targeted water, sanitation, and hygiene (WASH) interventions have the potential to reduce cholera transmission in cholera hotspots around cholera cases. The objective of this study was to expand the scope of the Cholera-Hospital-Based-Intervention-for-7-Days (CHoBI7) program, focused on cholera patient households, for delivery in cholera hotspots in urban slums in Dhaka, Bangladesh. Thirty-one semi-structured interviews were conducted in cholera hotspots around cholera patients, and three intervention planning workshops were conducted to inform modifications needed to the CHoBI7 program. After exploratory interviews, a two-phase, iterative pilot study was conducted for 9 months to test the developed CHoBI7 Cholera Rapid Response program among 180 participants to further inform modifications to intervention content and delivery. Findings from pilot participant interviews highlighted the need to adapt intervention content for delivery at the compound-rather than household-level, given an environment with multiple households sharing a water source, toilets, and kitchen facilities. This was addressed by conducting a "ring session" for intervention delivery in cholera hotspots for households to discuss how to improve their shared facilities together and encourage a compound-level commitment to promoted WASH behaviors and placement of soapy water bottles in shared spaces. Based on the low number of soapy water bottles observed in communal spaces during the first iteration of the pilot, we also added context-specific examples using the narratives of families in mobile messages to encourage WASH behavioral recommendations. Formative research identified important considerations for the modifications needed to tailor the CHoBI7 program for delivery in cholera hotspots in urban Bangladesh.

Fecal Sampling of Soil, Food, Hand, and Surface Samples from Households in Urban Slums of Dhaka, Bangladesh: An Evidence-Based Development of Baby Water, Sanitation, and Hygiene Interventions.

The aim of this study was to identify the exposure pathways of fecal pathogens for a pediatric population living in the urban slums of Bangladesh. A total of 252 soil, food, surface, and hand rinse samples were collected from the pilot households with children less than 5 years of age. All samples were analyzed using the IDEXX Quanti-Tray System (Colilert-18) to enumerate fecal indicator bacteria Escherichia coli. Escherichia coli was detected in all soil samples collected from children play spaces (N = 46), 35% of objects and surfaces children frequently put in their mouths, and 31% of child food samples. Thirty-three percent of hand samples from the child and 46% of hand samples from the caregiver had detectable E. coli. These findings showed high fecal contamination of soil, food, and on hands and surfaces in households with young children and demonstrate the need for interventions reducing these exposure pathways for susceptible pediatric populations.

Low Fruit and Vegetable Consumption Associated with Linear Growth Faltering among Children in Urban Bangladesh.

The objective of this study was to examine the association between dietary diversity and child growth among children 6 to 23 months of age in urban slums of Bangladesh. This prospective cohort study enrolled 192 participants 6 to 23 months of age in Dhaka, Bangladesh. A total of 170 children with follow-up anthropometric data were included in the analysis. To collect dietary intake information for children 6 to 23 months of age, consumption of five or more of the following eight minimum dietary diversity food groups was recorded using 24-hour dietary recall at enrollment provided by the child's caregiver: 1) breast milk; 2) grains, roots, and tubers; 3) legumes and nuts; 4) dairy products; 5) flesh foods; 6) eggs; 7) vitamin A-rich fruits and vegetables; and 8) other fruits and vegetables. Height and weight were measured at baseline and at a 12-month follow-up. Fifty-five percent of children (106 of 192) consumed five or more of the eight minimum dietary diversity food groups during their first visit to assess dietary intake. Eighty-two percent of children (157 of 192) had a report of consuming an animal source of food (e.g., eggs, diary, flesh foods) in the past 24 hours, 85% (164 of 192) consumed any source of protein (e.g., eggs, diary, flesh foods, nuts, and legumes), and 65% of children (125 of 192) were reported to consume any fruits and vegetables. Child consumption of fruits and vegetables was associated positively with change in length-for-age z-scores from baseline to the 12-month follow-up (coefficient, 0.86; 95% CI, 0.03-1.68). Inadequate fruit and vegetable consumption was associated with linear growth faltering among the young children residing in urban Dhaka, Bangladesh. These findings demonstrate the need for effective interventions to increase fruit and vegetable consumption in this susceptible pediatric population.

Household Bird Ownership is Associated with Respiratory Illness among Young Children in Urban Bangladesh (CHoBI7 Program).

There is limited evidence on the association between animal ownership and respiratory illness among young children in low- and middle-income countries. In this study, we examined the association between animal ownership and respiratory illness among children younger than 5 years of age enrolled in a prospective cohort study in urban Bangladesh. This prospective cohort study enrolled 884 participants younger than 5 years of age in Dhaka, Bangladesh. At baseline, trained research assistants administered caregivers of children younger than 5 years of age a questionnaire on household animal ownership. Animal ownership was defined as owning chickens, birds other than chickens, cats, and dogs. Respiratory surveillance was conducted monthly for children based on caregiver-reported coughing, rapid breathing, and difficulty breathing in the past 2 weeks during the 12-month study period. At baseline, 48% of children (424 of 884) had reports of coughing, 5% (40 of 884) had difficulty breathing, 3% (25 of 884) had rapid breathing, and 49% (431 of 884) had reports of any of these three respiratory symptoms. Seventeen percent of children (151 of 884) resided in a household that owned an animal. Children residing in households reporting bird ownership had a significantly greater odds of coughing (odds ratio, 1.14; 95% CI, 1.02-1.28) and any of the three respiratory symptoms in the past 2 weeks (odds ratio, 1.14; 95% CI, 1.02-1.28). Household bird ownership was associated with respiratory illness in young children. These findings suggest that interventions aiming to reduce young children's exposure to domestic animals should extend to include birds other than chickens.

Psychosocial Factors Mediating the Effect of the CHoBI7 Mobile Health Program on Handwashing With Soap and Household Stored Water Quality: A Randomized Controlled Trial.

Household members of diarrhea patients are at higher risk of developing diarrheal diseases (>100 times for cholera) than the general population during the 7 days after the diarrhea patient is admitted at a health facility. There is growing evidence demonstrating that theory-driven water, sanitation, and hygiene (WASH) interventions are likely to yield greater behavior change than those based on health education alone. The Cholera Hospital-Based Intervention for 7-Days (CHoBI7) mobile health (mHealth) program is a theory-driven WASH intervention initially delivered to a diarrhea patient by a health promoter during a health facility visit and reinforced through weekly voice and text messages. In the recent randomized controlled trial (RCT) of the CHoBI7-mHealth program in Bangladesh, this intervention significantly reduced diarrheal disease and stunting, and increased handwashing with soap and stored drinking water quality over the 12-month program period. The aim of this study was to assess the underlying mechanism of change of this intervention. Handwashing with soap was measured by 5-hour structured observation. Stored drinking water quality was assessed by the presence of Escherichia coli during unannounced spot checks. Psychosocial factors were measured among 1,468 participants in the CHoBI7-mHealth RCT. Perceived susceptibility, response efficacy, self-efficacy, dirt reactivity, and diarrhea knowledge were mediators of the CHoBI7-mHealth program's effect on stored drinking water quality at the 1-week follow-up. Self-efficacy, response efficacy, and diarrhea knowledge were mediators of the intervention's effect on handwashing with soap habit maintenance and stored drinking water quality at the 12-month follow-up. This study demonstrates how theory-driven approaches for intervention design can facilitate WASH behavior change.

Diarrhea Prevalence and Child Growth Faltering Are Associated with Subsequent Adverse Child Developmental Outcomes in Bangladesh (CHoBI7 Program).

Millions of young children annually are not meeting their developmental potential in low- and middle-income countries. Previous studies have shown that diarrheal diseases during early life are associated with subsequent malnutrition. This prospective cohort study of 576 children under 5 years was conducted in urban Dhaka, Bangladesh, to investigate the association between diarrhea prevalence, child growth, and child cognitive developmental outcomes. Height and weight were measured at baseline and a 12-month follow-up. Diarrhea prevalence was assessed through monthly surveillance visits. Developmental outcomes were assessed by communication, fine motor, gross motor, personal social, problem-solving, and combined developmental scores measured by the Extended Ages and Stages Questionnaire (EASQ) at the 12-month follow-up visit. To assess the association between diarrhea prevalence, child growth, and child cognitive developmental outcomes, linear regression models were fit using generalized estimating equations to account for clustering at the household level and to approximate 95% CIs. Diarrhea prevalence was negatively associated with change in height-for-age (HAZ) Z-scores from baseline to the 12-month follow-up (coefficient -0.85 [95% CI: -1.42, -0.28]). Diarrhea prevalence was a significant predictor of combined EASQ Z-scores with and without baseline stunting included in the model (-0.89 [95% CI: -1.67, -0.09] [baseline stunting included]) and (-0.88 [95% CI: -1.69, -0.07]). Change in HAZ from baseline to the 12-month follow-up was positively associated with follow-up combined EASQ Z-scores (0.28 [95% CI: 0.15, 0.42]). High diarrhea prevalence and linear growth faltering were associated with negative cognitive developmental outcomes among children residing in urban Dhaka, Bangladesh. Furthermore, high diarrhea prevalence was associated with negative child cognitive developmental outcomes with stunting included in the model, suggesting an effect of diarrhea on cognition independent of stunting.

Fecal Contamination on the Household Compound and in Water Sources are Associated with Subsequent Diarrhea in Young Children in Urban Bangladesh (CHoBI7 Program).

We investigated the environmental and individual-level risk factors for diarrheal disease among young children in slum areas of Dhaka, Bangladesh. A prospective cohort study was conducted among 884 children under 5 years of age. Caregiver reports were collected on sociodemographic factors and hygiene behaviors. Diarrhea surveillance data was collected monthly based on caregiver-reported diarrhea for children in the past 2 weeks during the 12-month study period. Unannounced spot checks of the household compound were performed at 1, 3, 6, 9, and 12 months after enrollment to check for the presence of feces (animal or human) and the presence of animals in the child's sleeping space, to assess child and caregiver hands for the presence of dirt, and to collect samples of the household's source and stored drinking water. Children with feces found on the household compound during spot checks had a significantly higher odds of diarrhea (odds ratio: 1.71; 95% confidence interval: 1.23-2.38). Children residing in households with > 100 colony forming units/100 mL Escherichia coli in source drinking water had a significantly higher odds of diarrhea (OR: 1.43; 95% CI: 1.06-1.92). The presence of feces on the household compound and source drinking water with > 100 colony forming units/100 mL E. coli were significant risk factors for diarrheal disease for children < 5 years of age in slum areas of Dhaka, Bangladesh. These findings demonstrate the urgent need for comprehensive interventions to reduce fecal contamination on the household compound to protect the health of susceptible pediatric populations.

Formative research to scale up a handwashing with soap and water treatment intervention for household members of diarrhea patients in health facilities in Dhaka, Bangladesh (CHoBI7 program).

BACKGROUND: During the time a diarrhea patient presents at a health facility, the household members of the patient are at higher risk of developing diarrheal diseases (> 100 times for cholera) than the general population. The Cholera-Hospital-based-Intervention-for-7-Days (CHoBI7) is a health facility-initiated water treatment and handwashing with soap intervention designed to reduce transmission of diarrheal diseases between patients and their household members. The present research aimed to (1) develop a scalable approach to integrate the CHoBI7 intervention program into services provided at government and private health facilities in Bangladesh; and (2) tailor the intervention program for the household members of all diarrhea patients, irrespective of the etiology of disease. METHODS: We conducted 8 months of formative research, including 60 semi-structured interviews, 2 group discussions, and a pilot study. Thirty-two interviews were conducted with diarrhea patients and their family caregivers, government stakeholders, and health care providers both to explore existing WASH and diarrhea patient care practices in health facilities and to identify considerations for scaling the CHoBI7 program. Fifty-two diarrhea patient households participated in a pilot study of a modified version of the CHoBI7 intervention program for tailoring. Twenty-eight interviews and 2 group discussions were conducted with pilot households to explore experiences with and recommendations for intervention delivery. RESULTS: The intervention program was modified based on formative research findings. Pilot study participants recognized the benefits of the CHoBI7 intervention program and made suggestions to improve the acceptability and feasibility of the intervention. Modifications included 1) providing additional pictorial modules, cues to action, enabling technologies, and supplies for safe drinking water and handwashing with soap behaviors in the health facility; 2) switching out technology prone to breaks and leaks as well as sourcing plastic technologies from a high-quality, local manufacturer; and 3) including instructions discouraging the non-use or misuse of technologies and supplies. Considerations for scalability include the local availability and marketing of enabling technologies and supplies, staff for program delivery in health facilities, and potential integration into existing government or health promotion programs. CONCLUSIONS: Formative research identified important considerations for the content, delivery, and scalability of the CHoBI7 health facility-initiated WASH intervention program.

Effect of a water, sanitation and hygiene program on handwashing with soap among household members of diarrhoea patients in healthcare facilities in Bangladesh: a cluster-randomised controlled trial of the CHoBI7 mobile health program.

OBJECTIVE: The Cholera-Hospital-Based-Intervention-for-7-days (CHoBI7) is a water treatment and handwashing with soap intervention for diarrhoea patients and their household members which is initially delivered in a healthcare facility setting. This study evaluated the effectiveness of CHoBI7 program delivery in increasing handwashing with soap in a healthcare facility setting among diarrhoea patients and their household members. METHODS: A randomised controlled trial of the CHoBI7 program was conducted among 404 diarrhoea patients and their accompanying household members in healthcare facilities in Dhaka, Bangladesh. The 'Standard Message' Arm received the standard message given in Bangladesh to diarrhoea patients on the use of oral rehydration solution. The 'Health Facility Visit + Soapy Water' Arm received the standard message, the CHoBI7 communication module delivered bedside to the patient; and a soapy water bottle in the healthcare facility. The 'Health Facility Visit + Handwashing Station' Arm received this same intervention plus a small plastic handwashing station. Within 24 h of intervention delivery, three-hour structured observation of handwashing practices at stool/vomit- and food-related events (key events) was conducted in healthcare facilities of diarrhoea patients and their accompanying household members. RESULTS: Compared to the Standard Message Arm, there was significantly more handwashing with soap at key events in both the Health Facility Visit + Soapy Water Arm (51% vs. 25 %) (Odds Ratio: 3.02; (95% Confidence Interval (CI): 1.41, 6.45) and the Health Facility Visit + Handwashing Station Arm (58% vs. 25%) OR: 4.12; (95% CI: 1.86, 9.14). CONCLUSION: These findings demonstrate that delivery of the CHoBI7 communication module and provision of a soapy water bottle to diarrhoea patients and their accompanying household members presents a promising approach to increase handwashing with soap among this high risk population in a healthcare facility setting in Bangladesh.

OBJECTIF: Le programme (CHoBI7Cholera-Hospital-Based-Intervention-for-7-days) est une intervention de traitement de l'eau et de lavage des mains avec du savon pour les patients et les membres de leur famille qui est initialement administrée dans un établissement de santé. Cette étude a évalué l'efficacité du programme CHoBI7 pour augmenter le lavage des mains au savon dans les établissements de santé. MÉTHODES: Un essai contrôlé randomisé du programme CHoBI7 a été mené auprès de 404 patients atteints de diarrhée et des membres de leur famille qui les accompagnent dans des établissements de santé à Dhaka, au Bangladesh. Le bras "Message standard" a reçu le message standard donné au Bangladesh aux patients atteints de diarrhée sur l'utilisation de la solution de réhydratation orale. Le bras "Visite de l'établissement de santé + eau savonneuse" a reçu le message standard, le module de communication CHoBI7 a été délivré au chevet du patient et une bouteille d'eau savonneuse dans l'établissement de santé. Le bras "Visite de l'établissement de santé + station de lavage des mains" a reçu la même intervention, ainsi qu'une petite station de lavage des mains en plastique. Dans les 24 heures suivant l'intervention, une observation structurée de trois heures des pratiques de lavage des mains lors d'événements liés aux selles/vomis et à la nourriture (événements clés) a été menée dans les établissements de santé. RÉSULTATS: Par rapport au bras 'Message standard', le lavage des mains au savon était significativement plus fréquent lors des événements clés dans le bras 'Visite de l'établissement de santé + Station de lavage des mains' (58% contre 25%) (rapport de cotes (OR): 4,12 ; (intervalle de confiance (IC) de 95%: 1,86-9,14) et dans le bras 'Visite de l'établissement de santé + Eau savonneuse' (51% contre 25%) (OR: 3,02 ; (IC95% : 1,41-6,45). CONCLUSION: Ces résultats démontrent que l'implémentation du module CHoBI7 constitue une approche prometteuse pour augmenter le lavage des mains au savon dans un établissement de santé au Bangladesh.

Child mouthing of soil and presence of animals in child sleeping spaces are associated with growth faltering among young children in Dhaka, Bangladesh (CHoBI7 Program).

OBJECTIVE: The objective of the study was to investigate potential risk factors for growth faltering among children under 5 years of age. METHOD: We conducted a prospective cohort study of 553 children under 5 years from diarrhoea patient households in urban Dhaka, Bangladesh. Height and weight measurements were obtained at baseline and at a 12-month follow-up. Caregivers of young children were administered a monthly questionnaire on household sociodemographic characteristics and hygiene practices. RESULTS: Children with caregiver reports of mouthing soil at the majority of household visits had a significant reduction in their height-for-age z-scores (HAZ) from baseline to the 12-month follow-up (ΔHAZ: -0.28 (95% confidence interval (CI): -0.51, -0.05)). A significant reduction in HAZ was also observed for children in households with animals in their sleeping space (ΔHAZ: -0.37 (95% CI: -0.71, -0.04)). CONCLUSION: These findings provide further evidence to support the hypothesis that child mouthing of soil and the presence of animals in the child's sleeping space are potential risk factors for growth faltering among young children. Interventions are urgently needed to provide clean play and sleeping spaces for young children to reduce exposure to faecal pathogens through child mouthing.

OBJECTIF: L'objectif de l'étude était d'examiner les facteurs de risque potentiels de retard de croissance chez les enfants de moins de 5 ans. MÉTHODE: Nous avons mené une étude de cohorte prospective sur 553 enfants de moins de 5 ans provenant de ménages avec des patients diarrhéiques dans la ville de Dhaka, au Bangladesh. Les mesures de taille et de poids ont été obtenues au départ et à 12 mois de suivi. Les personnes s'occupant de jeunes enfants (les gardiens) ont reçu un questionnaire mensuel sur les caractéristiques sociodémographiques des ménages et les pratiques d'hygiène. RÉSULTATS: Les enfants pour lesquels les gardiens ont déclaré qu'ils mâchouillaient de la terre lors de la majorité des visites à domicile présentaient une diminution du score Z de taille pour l'âge (TAZ) de manière significative de l'âge de référence au 12 mois de suivi (ΔTAZ −0,28 (intervalle de confiance (IC) à 95%: −0,51, −0,05)). Une réduction significative des TAZ a également été observée pour les enfants des ménages ayant des animaux dans leur espace de couchage (ΔTAZ −0,37 (IC95%: −0,71, −0,04)). CONCLUSION: Ces résultats apportent des données supplémentaires pour appuyer l'hypothèse selon laquelle le fait que l'enfant mâchouille de la terre et la présence d'animaux dans son espace de couchage sont des facteurs de risque potentiels de retard de croissance chez les jeunes enfants. Des interventions sont urgemment nécessaires pour fournir des espaces de jeu et de sommeil sains aux jeunes enfants afin de réduire l'exposition aux agents pathogènes fécaux par le mâchouillement des enfants.

Genetic relatedness of Vibrio cholerae isolates within and between households during outbreaks in Dhaka, Bangladesh.

BACKGROUND: Household contacts of cholera patients have a 100 times higher risk of developing a cholera infection than the general population. To compare the genetic relatedness of clinical and water source Vibrio cholerae isolates from cholera patients' households across three outbreaks, we analyzed these isolates using whole-genome-sequencing (WGS) and multilocus variable-number tandem-repeat analysis (MLVA). RESULTS: The WGS analyses revealed that 80% of households had source water isolates that were more closely related to clinical isolates from the same household than to any other isolates. While in another 20% of households an isolate from a person was more closely related to clinical isolates from another household than to source water isolates from their own household. The mean pairwise differences in single nucleotide-variant (SNV) counts for isolates from the same household were significantly lower than those for different households (2.4 vs. 7.7 p < 0.0001), and isolates from the same outbreak had significantly fewer mean pairwise differences compared to isolates from different outbreaks (mean: 6.2 vs. 8.0, p < 0.0001). Based on MLVA in outbreak 1, we observed that the majority of households had clinical isolates with MLVA genotypes related to other clinical isolates and unrelated to water source isolates from the same household. While in outbreak 3, there were different MLVA genotypes between households, however within the majority of households, the clinical and water source isolates had the same MLVA genotypes. The beginning of outbreak 2 resembled outbreak 1 and the latter part resembled outbreak 3. We validated our use of MLVA by comparing it to WGS. Isolates with the identical MLVA genotype had significantly fewer mean pairwise SNV differences than those isolates with different MLVA genotypes (mean: 4.8 vs. 7.7, p < 0.0001). Furthermore, consistent with WGS results, the number of pairwise differences in the five MLVA loci for isolates within the same household was significantly lower than isolates from different households (mean: 1.6 vs. 3.0, p < 0.0001). CONCLUSION: These results suggest that transmission patterns for cholera are a combination of person-to-person and water-to-person cholera transmission with the proportions of the two modes varying within and between outbreaks.