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Microbiological water quality is usually assessed by the identification of Escherichia coli ( E. coli ), a fecal indicator. The hydrogen sulfide (H 2 S) test is an inexpensive, easy-to-use, and portable alternative field-based water quality test. Our study evaluated the H 2 S test's effectiveness as a water quality indicator for diarrhea risk. Field workers collected stored drinking water samples for H 2 S analysis and detection of E. coli by membrane filtration and measured caregiver-reported diarrhea among children < 5 years in the same households 1 month later. We assessed the association between the H 2 S test (incubated for 24 hours and 48 hours) and diarrhea prevalence, with 2-day and 7-day symptom recall periods ( N = 1,348). We determined the sensitivity, specificity, and positive and negative predictive value (PPV, NPV) of the H 2 S test compared with E. coli ( N = 525). Controlling for potentially confounding covariates, H 2 S-positive water (at 24 or 48 hours) was not associated with 2-day diarrhea prevalence (24-hour prevalence ratio [PR] = 1.03, 95% confidence interval [CI]: 0.63-1.69; 48-hour PR = 0.89, 95% CI: 0.58-1.38) or 7-day diarrhea prevalence (24-hour PR = 1.17, 95% CI: 0.76-1.78; 48-hour PR = 1.21, 95% CI: 0.81-1.80). The sensitivity, PPV, and NPV of the H 2 S test was significantly higher when the H 2 S test was incubated for 48 versus 24 hours whereas specificity showed the opposite trend. H 2 S test sensitivity, PPV, and NPV increased with increasing E. coli levels, consistent with previous evidence that the H 2 S test is a useful water quality tool in high-contamination settings. However, our results suggest that the H 2 S test is not an effective indicator for waterborne diarrhea.

In preparation for a larger trial, the Water, Sanitation, and Hygiene (WASH) Benefits pilot study enrolled 72 villages and 499 subjects in two closely related randomized trials of WASH interventions in rural western Kenya. Intervention households received hardware and promotion for one of the following: water treatment, sanitation and latrine improvements, handwashing with soap, or the combination of all three. Interventions were clustered by village. A follow-up survey was conducted 4 months after intervention delivery to assess uptake. Intervention households were significantly more likely than controls to have chlorinated stored water (36-60 percentage point increases), covers over latrine drop holes (55-75 percentage point increases), less stool visible on latrine floors (16-47 percentage point reductions), and a place for handwashing (71-85 percentage point increases) with soap available (49-66 percentage point increases). The high uptake in all arms shows that combined interventions can achieve high short-term adoption rates if well-designed., (© The American Society of Tropical Medicine and Hygiene.)

Discreet collection of spot check observations to measure household hygiene conditions is a common measurement technique in epidemiologic studies of hygiene in low-income countries. The objective of this study was to determine whether the collection of spot check observations in longitudinal studies could itself induce reactivity (i.e., change participant behavior). We analyzed data from a 12-month prospective cohort study in rural Tamil Nadu, India that was conducted in the absence of any hygiene or toilet promotion activities. Our data included hygiene and toilet spot checks from 10,427 household visits. We found substantial evidence of participant reactivity to spot check observations of hygiene practices that were easy to modify on short notice. For example, soap observed at the household's primary handwashing location increased from 49% at enrollment to 81% by the fourth visit and remained at or above 77% for the remainder of the study., (© The American Society of Tropical Medicine and Hygiene.)

In this large-scale longitudinal study conducted in rural Southern India, we compared a presence/absence hydrogen sulfide (H2S) test with quantitative assays for total coliforms and Escherichia coli as measures of water quality, health risk, and water supply vulnerability to microbial contamination. None of the three indicators showed a significant association with child diarrhea. The presence of H2S in a water sample was associated with higher levels of total coliform species that may have included E. coli but that were not restricted to E. coli. In addition, we observed a strong relationship between the percent positive H2S test results and total coliform levels among water source samples (R(2) = 0.87). The consistent relationships between H2S and total coliform levels indicate that presence/absence of H2S tests provide a cost-effective option for assessing both the vulnerability of water supplies to microbial contamination and the results of water quality management and risk mitigation efforts.

Nonmalarial acute undifferentiated fever (NMAUF) refers to a febrile illness with no indication of an organ-specific disease after diagnosis of malaria has been excluded. In developing countries, the empirical treatment of NMAUFs with antimalarial drugs continues even in the era of highly specific rapid diagnostic tests (RDTs) for malaria. We carried out a retrospective review of patients with fever admitted to a rural teaching hospital in central India. We categorized patients with NMAUF into different clinical syndromes and determined their demographic profile, inhospital course, and the pattern of antimalarial use. The study sample included 1,197 adult patients who were investigated for malaria; 1,053 (88%) of them had NMAUF, and use of further diagnostics in this group was limited. Despite one or more negative tests for malaria, many patients (39.9%, 95% CI 37.0-43.3) received antimalarial drugs. These results suggest a need for guidelines and training to improve empirical treatment of NMAUF.

We conducted a systematic review of all studies that measured diarrheal health impacts in children and the impact on water quality of point-of-use chlorine drinking water treatment. Twenty-one relevant studies were identified from > 856 screened abstracts. Data were extracted and combined using meta-analysis to provide summary estimates of the intervention effect. The intervention reduced the risk of child diarrhea (pooled relative risk: 0.71, 0.58-0.87) and it reduced the risk of stored water contamination with Escherichia coli (pooled relative risk: 0.20, 0.13-0.30). A major finding from this review is that nearly all trials on this topic have been short (median length was 30 weeks). Although not statistically significant, we observed an attenuation of the intervention's reduction of child diarrhea in longer trials. Future studies with multi-year follow-up are required to assess the long-term acceptability and sustainability of health impacts shown by the shorter trials identified in this review.