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.

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.

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 for the Design of a Baby Water, Sanitation, and Hygiene Mobile Health Program in Bangladesh (CHoBI7 Mobile Health Program).

Poor food hygiene practices, child feces not being disposed of in a latrine, child mouthing of contaminated fomites, and poor hand hygiene of caregivers have been associated with diarrheal diseases, environmental enteropathy, and impaired growth in young children. Mobile health (mHealth) programs present a low-cost approach to delivering water, sanitation, and hygiene (WASH) programs. We conducted a theory-driven and evidence-based approach to formative research and intervention development to design and pilot test a Baby WASH mHealth program targeting food hygiene, child mouthing, and child feces disposal behaviors in urban Dhaka, Bangladesh. Formative research activities included 31 semi-structured interviews, five group discussions, six mHealth workshops, and a three-phase iterative pilot study among 102 households. Findings from semi-structured interviews and group discussions indicate that caregivers of young children have relatively high awareness of the need for safer food hygiene, child mouthing, and child feces disposal practices, but are limited by existing household responsibilities and restricted access to enabling technology that would facilitate practicing recommended behaviors. The piloted Baby WASH mHealth program was well-received by households. This study presents a theory-driven and evidence-based approach for intervention development that can be implemented for the development of future WASH mHealth programs in low-resource settings.

Promotion of Cholera Awareness Among Households of Cholera Patients: A Randomized Controlled Trial of the Cholera-Hospital-Based-Intervention-for-7 Days (CHoBI7) Intervention.

Previous studies have demonstrated that household contacts of cholera patients are highly susceptible to cholera infections for a 7-day period after the presentation of the index patient in the hospital. However, there is no standard of care to prevent cholera transmission in this high-risk population. Furthermore, there is limited information available on awareness of cholera transmission and prevention among cholera patients and their household contacts. To initiate a standard of care for this high-risk population, we developed the Cholera-Hospital-Based-Intervention-for-7-Days (CHoBI7), which delivers a handwashing with soap and water treatment intervention to household contacts during the time they spend with the admitted cholera patient in the hospital and reinforces these messages through home visits. To test CHoBI7, we conducted a randomized controlled trial among 302 intervention cholera patient household members and 302 control cholera patient household members in Dhaka, Bangladesh. In this study, we evaluated the effectiveness of the CHoBI7 intervention in increasing awareness of cholera transmission and prevention, and the key times for handwashing with soap. We observed a significant increase in cholera knowledge score in the intervention arm compared with the control arm at both the 1-week follow-up {score coefficient = 2.34 (95% confidence interval [CI] = 1.96, 2.71)} and 6 to 12-month follow-up period (score coefficient = 1.59 [95% CI = 1.05, 2.13]). This 1-week hospital- and home-based intervention led to a significant increase in knowledge of cholera transmission and prevention which was sustained 6 to 12 months post-intervention. These findings suggest that the CHoBI7 intervention presents a promising approach to increase cholera awareness among this high-risk population.

Chlorination of Household Drinking Water Among Cholera Patients' Households to Prevent Transmission of Toxigenic Vibrio cholerae in Dhaka, Bangladesh: CHoBI7 Trial.

Household members of cholera patients are at a 100 times higher risk of cholera infections than the general population because of shared contaminated drinking water sources and secondary transmission through poor household hygiene practices. In this study, we investigated the bactericidal concentration of free chlorine required to inactivate Vibrio cholerae in household drinking water in Dhaka, Bangladesh. In laboratory experiments, we found that the concentrations of free chlorine required to inactivate 105 colony-forming units (CFU)/mL of V. cholerae serogroups O1 and O139 were 0.1 mg/L and 0.2 mg/L, respectively. The concentration of free chlorine generated by a single chlorine tablet (sodium dichloroisocyanurate [33 mg]) after a 30-minute reaction time in a 10-L sealed vessel containing Dhaka city municipal supply water was 1.8 mg/L; and the concentration declined to 0.26 mg/L after 24 hours. In field measurements, water collected from 165 households enrolled in a randomized controlled trial (RCT) of a chlorine and handwashing with soap intervention (Cholera-Hospital-Based-Intervention-for-7-Days [CHoBI7]), we observed significantly higher free chlorine concentrations in the 82 intervention arm households (mean = 1.12 mg/L, standard deviation [SD] = 0.52, range = 0.07-2.6 mg/L) compared with the 83 control households (0.017 mg/L, SD = 0.01, range = 0-0.06 mg/L) (P < 0.001) during spot check visits. These findings suggest that point-of-use chlorine tablets present an effective approach to inactivate V. cholerae from drinking water in households of cholera patients in Dhaka city. This result is consistent with the findings from the RCT of CHoBI7 which found that this intervention led to a significant reduction in symptomatic cholera infections among household members of cholera patients and no stored drinking water samples with detectable V. cholerae.

Feasibility and effectiveness of oral cholera vaccine in an urban endemic setting in Bangladesh: a cluster randomised open-label trial.

BACKGROUND: Cholera is endemic in Bangladesh with epidemics occurring each year. The decision to use a cheap oral killed whole-cell cholera vaccine to control the disease depends on the feasibility and effectiveness of vaccination when delivered in a public health setting. We therefore assessed the feasibility and protective effect of delivering such a vaccine through routine government services in urban Bangladesh and evaluated the benefit of adding behavioural interventions to encourage safe drinking water and hand washing to vaccination in this setting. METHODS: We did this cluster-randomised open-label trial in Dhaka, Bangladesh. We randomly assigned 90 clusters (1:1:1) to vaccination only, vaccination and behavioural change, or no intervention. The primary outcome was overall protective effectiveness, assessed as the risk of severely dehydrating cholera during 2 years after vaccination for all individuals present at time of the second dose. This study is registered with ClinicalTrials.gov, number NCT01339845. FINDINGS: Of 268,896 people present at baseline, we analysed 267,270: 94,675 assigned to vaccination only, 92,539 assigned to vaccination and behavioural change, and 80,056 assigned to non-intervention. Vaccine coverage was 65% in the vaccination only group and 66% in the vaccination and behavioural change group. Overall protective effectiveness was 37% (95% CI lower bound 18%; p=0·002) in the vaccination group and 45% (95% CI lower bound 24%; p=0·001) in the vaccination and behavioural change group. We recorded no vaccine-related serious adverse events. INTERPRETATION: Our findings provide the first indication of the effect of delivering an oral killed whole-cell cholera vaccine to poor urban populations with endemic cholera using routine government services and will help policy makers to formulate vaccination strategies to reduce the burden of severely dehydrating cholera in such populations. FUNDING: Bill & Melinda Gates Foundation.