Quality of Drinking-water at Source and Point-ofconsumption\u2014 Drinking Cup As a High Potential Recontamination Risk: A Field Study in Bolivia

In-house contamination of drinking-water is a persistent problem in developing countries. This study aimed at identifying critical points of contamination and determining the extent of recontamination after water treatment. In total, 81 households were visited, and 347 water samples from their current sources of water, transport vessels, treated water, and drinking vessels were analyzed. The quality of water was assessed using Escherichia coli as an indicator for faecal contamination. The concentration of E. coli increased significantly from the water source [median=0 colony-forming unit (CFU)/100 mL, interquartile range (IQR: 0-13)] to the drinking cup (median=8 CFU/100 mL; IQR: 0-550; n=81, z=-3.7, p<0.001). About two-thirds (34/52) of drinking vessels were contaminated with E. coli. Although boiling and solar disinfection of water (SODIS) improved the quality of drinking-water (median=0 CFU/100 mL; IQR: 0-0.05), recontamination at the point-of-consumption significantly reduced the quality of water in the cups (median=8, IQR: 0-500; n=45, z=-2.4, p=0.015). Home-based interventions in disinfection of water may not guarantee health benefits without complementary hygiene education due to the risk of posttreatment contamination

Reporting Diarrhoea through a Vernacular Term in Quechua-speaking Settings of Rural Bolivia

Field studies often usecaregiver-reporteddiarrhoeaandrelatedsymptoms to measure childmorbidity.There are various vernacular terms to define diarrhoea that vary across the local cultural contexts. The relationship between vernacular definitions of diarrhoea and symptoms-based definitions is not well-documented. This paper describes the association of the vernacular Quechua term k\u2019echalera with the symptoms-based standard definition of diarrhoea in rural Bolivian settings. During a cluster randomized trial in rural Bolivia, both signs and symptoms of diarrhoea and reports of k\u2019echalera were collected for children aged less than five years. Reported k\u2019echalera were found to be associated with important changes in stool frequency, consistency, and presence of blood and mucus. Reported k\u2019echalera were highly related to three of four recorded categories of watery stool. The intermediate (milk-rice) stool consistency, which fits into the definition of watery stool, was not strongly related to k\u2019echalera. Mucus in the stool was also associated with k\u2019echalera; however, its presence in k\u2019echalera-free days accounted for at least 50% of the possible false negatives. The sensitivity and specificity of the term k\u2019echalera were estimated by Bayesian methods, allowing for both symptoms of diarrhoea and reports of k\u2019echalera to be subject to diagnosis error. An average specificity of at least 97% and the sensitivity of at least 50% were obtained. The findings suggest that the use of k\u2019echalera would identify fewer cases of diarrhoea than a symptom-based definition in rural Bolivia