Risk factors for diarrheagenic Escherichia coli infection in children aged 6-24 months in peri-urban community, Nairobi, Kenya.

Escherichia coli commonly inhabits the gut of humans and animals as part of their microbiota. Though mostly innocuous, some strains have virulence markers that make them pathogenic. This paper presents results of a cross-sectional epidemiological study examining prevalence of diarrheagenic E. coli (DEC) pathotypes in stool samples of asymptomatic healthy children (n = 540) in Dagoretti South subcounty, Nairobi, Kenya. E. coli was cultured and pathotyped using PCR to target specific virulence markers associated with Shiga-toxin, enteropathogenic, enterotoxigenic, enteroaggregative, entero-invasive and diffusely adherent E. coli. Overall prevalence of DEC pathotypes was 20.9% (113/540) with enteropathogenic E. coli being the most prevalent (34.1%), followed by enteroaggregative E. coli (23.5%) and Shiga-toxin producing E. coli (22.0%) among positive samples. We found evidence of co-infection with multiple pathotypes in 15% of the positive samples. Our models indicated that at the household level, carriage of DEC pathotypes in children was associated with age group [12-18 months] (OR 1.78; 95%CI 1.03-3.07; p = 0.04), eating matoke (mashed bananas) (OR 2.32; 95%CI 1.44-3.73; p = 0.001) and pulses/legumes (OR 1.74; 95%CI 1.01-2.99; p = 0.046) while livestock ownership or contact showed no significant association with DEC carriage (p>0.05). Our findings revealed significant prevalence of pathogenic DEC circulating among presumptive healthy children in the community. Since there has been no previous evidence of an association between any food type and DEC carriage, unhygienic handling, and preparation of matoke and pulses/legumes could be the reason for significant association with DEC carriage. Children 12-18 months old are more prone to DEC infections due to exploration and hand-to-mouth behavior. A detailed understanding is required on what proportion of positive cases developed severe symptomatology as well as fatal outcomes. The co-infection of pathotypes in the rapidly urbanizing environment needs to be investigated for hybrid or hetero-pathotype circulation that have been implicated in previous infection outbreaks.

Effect of a novel hygiene intervention on older children's handwashing in a humanitarian setting in Kahda district, Somalia: A cluster-randomised controlled equivalence trial.

INTRODUCTION: Improving handwashing with soap (HWWS) among children in humanitarian emergencies has the potential to reduce the transmission of several important infectious diseases. However, there is limited evidence on which approaches are effective in increasing HWWS among children in humanitarian settings. One recent innovation - the "Surprise Soap" intervention - was shown to be successful in a small-scale efficacy trial in a humanitarian setting in Iraq. This intervention includes soap with embedded toys delivered through a short household session comprising a glitter game, instruction of how and when to wash hands, and HWWS practice. Whilst promising, this approach has not been evaluated at programmatic scale in a complex humanitarian setting. METHODS: We conducted a cluster-randomised controlled equivalence trial of the Surprise Soap intervention in IDP camps in Kahda district, Somalia. Proportionate stratified random sampling was employed to recruit 200 households, with at least one child aged 5-12, across the camps. Eligible households were randomly allocated to receive the Surprise Soap intervention (n = 100) or an active comparator handwashing intervention in which plain soap was delivered in a short household session comprising standard health-based messaging and instruction of how and when to wash hands (n = 100). The primary outcome was the proportion of pre-specified occasions when HWWS was practiced by children aged 5-12 years, measured at baseline, 4-weeks, 12 weeks, and 16 weeks post invention delivery. RESULTS: HWWS increased in both groups (by 48 percentage points in the intervention group and 51 percentage points in the control group, at the 4-week follow up), however, there was no evidence of a difference in HWWS between the groups at the 4-week (adjusted RR (aRR) = 1.0, 95% CI 0.9-1.1), 12-week (aRR = 1.1, 95% CI 0.9-1.3), or 16-week (aRR = 1.0, 95% CI 0.9-1.2) follow-up. CONCLUSIONS: In this complex humanitarian setting, where soap availability and past exposure to handwashing promotion was low, it appears that well-designed, household-level targeted handwashing interventions that include soap provision can increase child HWWS and potentially reduce disease risk, but the Surprise Soap intervention offers no marginal benefit over a standard intervention that would justify the additional costs.

Measuring social norms related to handwashing: development and psychometric testing of measurement scales in a low-income urban setting in Abidjan, Côte d'Ivoire.

OBJECTIVES: To design and test the psychometric properties of four context-specific norm-related scales around handwashing with soap after toilet use: (1) perceived handwashing descriptive norms (HWDN); (2) perceived handwashing injunctive norms (HWIN); (3) perceived handwashing behaviour publicness (HWP); and (4) perceived handwashing outcome expectations (HWOE). DESIGN: Scale items were developed based on previous work and pilot tested in an iterative process. Content experts and members of the study team assessed the face validity of the items. The psychometric properties of the scales were assessed in a cross-sectional study. SETTING: The study was conducted in communal housing compounds in Abidjan, Côte d'Ivoire. PARTICIPANTS: A convenience sample of 201 adult residents (≥16 years old) from 60 housing compounds completed the final questionnaire. OUTCOME MEASURE: Confirmatory factor analysis was used to assess the goodness of fit of the global model. We assessed the internal consistency of each scale using Cronbach's alpha (α) and the Spearman-Brown coefficient (ρ). RESULTS: The results of the psychometric tests supported the construct validity of three of the four scales, with no factor identified for the HWOE (α=0.15). The HWDN and HWP scales were internally consistent with correlations of ρ=0.74 and ρ=0.63, respectively. The HWIN scale appeared reliable (α=0.83). CONCLUSION: We were able to design three reliable context-specific handwashing norm-related scales, specific to economically disadvantaged community settings in Abidjan, Côte d'Ivoire, but failed to construct a reliable scale to measure outcome expectations around handwashing. The social desirability of handwashing and the narrow content area of social norms constructs relating to handwashing present significant challenges when designing items to measure such constructs. Future studies attempting to measure handwashing norm-related constructs will need to take this into account when developing such scales, and take care to adapt their scales to their study context.