A rapid assessment of drinking water quality in informal settlements after a cholera outbreak in Nairobi, Kenya

Analyses of drinking water quality during a protracted cholera epidemic in Malawi - a cross-sectional study of key physicochemical and microbiological parameters

Anecdotal evidence and available literature indicated that contaminated water played a major role in spreading the prolonged cholera epidemic in Malawi from 2022 to 2023. This study assessed drinking water quality in 17 cholera-affected Malawi districts from February to April 2023. Six hundred and thirty-three records were analysed. The median counts/100 ml for thermotolerant coliform was 98 (interquartile range (IQR): 4-100) and that for Escherichia coli was 0 (IQR: 0-9). The drinking water in all (except one) districts was contaminated by thermotolerant coliform, while six districts had their drinking water sources contaminated by E. coli. The percentage of contaminated drinking water sources was significantly higher in shallow unprotected wells (80.0% for E. coli and 95.0% for thermotolerant coliform) and in households (55.8% for E. coli and 86.0% for thermotolerant coliform). Logistic regression showed that household water has three times more risk of being contaminated by E. coli and two and a half times more risk of being contaminated by thermotolerant coliform compared to other water sources. This study demonstrated widespread contamination of drinking water sources during a cholera epidemic in Malawi, which may be the plausible reason for the protracted nature of the epidemic.

Effect of domestic solid waste disposal practices on quality of drinking water sources in some rural communities of Akwa Ibom State, Nigeria

Poor waste disposal practices impinge on water quality. An assessment of the effect of domestic solid wastes disposal practices on microbial quality of drinking water sources was conducted in some rural communities of Akwa Ibom State, Nigeria. An ecological study design was adopted using quantitative methods and a multi-stage sampling technique for random selection of LGAs, communities, and households for the administration of questionnaires to 120 respondents within four communities. Microbiological analysis of water samples from various sources was also conducted. A total of 26 (43.3%) and 16 (26.7%) households in the coastal and upland areas respectively had waste disposal facilities, the remaining percentage dumped waste into rivers and nearby bushes. The majority of the coastal community dwellers defecate directly into water bodies or swamps due to a lack of faeces disposal facilities whereas all respondents in the upland areas had faeces disposal facilities though some were unimproved. The result of the microbial analysis showed that the coastal areas had a mean heterotrophic bacterial, coliform, and fungal count of 1.45(± 0.44) × 10⁵ cfu/ml, 0.90(± 0.27) × 10⁵ cfu/ml, and 1.75(± 0.50) × 10⁵ cfu/ml while the upland areas had 1.34(± 0.55) × 10⁵ cfu/ml, 0.65(± 0.36) × 10⁵ cfu/ml, and 1.88(± 0.58) × 10⁵ cfu/ml. There was no significant difference (P < 0.05) in microbial water quality between the coastal and upland areas besides the self-reported health problems. A moderate positive correlation was found between solid waste disposal practices and total bacterial count (r = 0.418**), and total coliform (r = 0.397**), P < 0.01. Most of the microorganisms isolated from drinking water in both settings were of public health importance. The result obtained from this study indicates very poor water quality in both settings. This implicates the poor solid waste disposal practices predominant in these communities and calls for immediate measures to secure the health of the rural community dwellers.

The nexus between improved water supply and water-borne diseases in urban areas in Africa: a scoping review

Background: The sub-Saharan Africa has the fastest rate of urbanisation in the world. However, infrastructure growth in the region is slower than urbanisation rates, leading to inadequate provision and access to basic services such as piped safe drinking water. Lack of sufficient access to safe water has the potential to increase the burden of waterborne diseases among these urbanising populations. This scoping review assesses how the relationship between waterborne diseases and water sufficiency in Africa has been studied. Methods: In April 2020, we searched the Web of Science, PubMed, Embase and Google Scholar databases for studies of African cities that examined the effect of insufficient piped water supply on selected waterborne disease and syndromes (cholera, typhoid, diarrhea, amoebiasis, dysentery, gastroneteritis, cryptosporidium, cyclosporiasis, giardiasis, rotavirus). Only studies conducted in cities that had more than half a million residents in 2014 were included. Results: A total of 32 studies in 24 cities from 17 countries were included in the study. Most studies used case-control, cross-sectional individual or ecological level study designs. Proportion of the study population with access to piped water was the common water availability metrics measured while amounts consumed per capita or water interruptions were seldom used in assessing sufficient water supply. Diarrhea, cholera and typhoid were the major diseases or syndromes used to understand the association between health and water sufficiency in urban areas. There was weak correlation between the study designs used and the association with health outcomes and water sufficiency metrics. Very few studies looked at change in health outcomes and water sufficiency over time. Conclusion: Surveillance of health outcomes and the trends in piped water quantity and mode of access should be prioritised in urban areas in Africa in order to implement interventions towards reducing the burden associated with waterborne diseases and syndromes.

Daily changes in household water access and quality in urban slums undermine global safe water monitoring programmes

Global drinking water monitoring programmes and studies on water quality in urban slums often overlook short-term temporal changes in water quality and health risks. The aim of this study was to quantify daily changes in household water access and quality in an urban slum in Malawi using a mixed-method approach. Household drinking water samples (n = 371) were collected and monitored for E. coli in tandem with a water access questionnaire (n = 481). E. coli concentrations in household drinking water changed daily, and no household had drinking water that was completely safe to drink every day. Seasonal changes in drinking water availability, intermittent supply, limited opening hours, and frequent breakdown of public water points contributed to poor access. Households relied on multiple water sources and regularly switched between sources to meet daily water needs. There were generally similar E. coli levels in water samples considered safe and unsafe by residents. This study provides the first empirical evidence that water quality, water access, and related health risks in urban slums change at much finer (daily) temporal scales than is conventionally monitored and reported globally. Our findings underscore that to advance progress towards Sustainable Development Goal (SDG) Target 6.1, it is necessary for global water monitoring initiatives to consider short-term changes in access and quality.

A protracted cholera outbreak among residents in an urban setting, Nairobi county, Kenya, 2015

Introduction

in 2015, a cholera outbreak was confirmed in Nairobi county, Kenya, which we investigated to identify risk factors for infection and recommend control measures.

Methods

we analyzed national cholera surveillance data to describe epidemiological patterns and carried out a case-control study to find reasons for the Nairobi county outbreak. Suspected cholera cases were Nairobi residents aged >2 years with acute watery diarrhea (>4 stools/≤12 hours) and illness onset 1-14 May 2015. Confirmed cases had Vibrio cholerae isolated from stool. Case-patients were frequency-matched to persons without diarrhea (1:2 by age group, residence), interviewed using standardized questionaires. Logistic regression identified factors associated with case status. Household water was analyzed for fecal coliforms and Escherichia coli.

Results

during December 2014-June 2015, 4,218 cholera cases including 282 (6.7%) confirmed cases and 79 deaths (case-fatality rate [CFR] 1.9%) were reported from 14 of 47 Kenyan counties. Nairobi county reported 781 (19.0 %) cases (attack rate, 18/100,000 persons), including 607 (78%) hospitalisations, 20 deaths (CFR 2.6%) and 55 laboratory-confirmed cases (7.0%). Seven (70%) of 10 water samples from communal water points had coliforms; one had Escherichia coli. Factors associated with cholera in Nairobi were drinking untreated water (adjusted odds ratio [aOR] 6.5, 95% confidence interval [CI] 2.3-18.8), lacking health education (aOR 2.4, CI 1.1-7.9) and eating food outside home (aOR 2.4, 95% CI 1.2-5.7).

Conclusion

we recommend safe water, health education, avoiding eating foods prepared outside home and improved sanitation in Nairobi county. Adherence to these practices could have prevented this protacted cholera outbreak.

Rapid drinking water safety estimation in cities: Piloting a globally scalable method in Cochabamba, Bolivia

BACKGROUND

Systematically collected and comparable data on drinking water safety at city-scale is currently unavailable, despite the stated importance of water safety monitoring at scale under the United Nations Sustainable Development Goals (SDGs). We developed a rapid drinking water quality assessment methodology intended to be replicable across all cities and useful for monitoring towards achieving SDG 6 (Clean Water and Sanitation).

METHODS

We collected drinking water samples at the point-of-consumption for basic microbial, physical and chemical water quality analysis and conducted household surveys on drinking water, sanitation, and hygiene access from 80 households in the city of Cochabamba over 1 week. We categorized the household's water service level according to the SDG 6 framework.

RESULTS

We estimated an average time requirement of 6.4 person-hours and a consumable cost of US $51 per household (n = 80). In this cross-sectional study, 71% of drinking water samples met World Health Organization (WHO) microbiological safety criteria, 96% met WHO chemical quality criteria, and all met WHO aesthetic quality criteria. However, only 18% of the households were categorized as having safely managed drinking water services. None met the criteria for having safely managed sanitation services; nonetheless, 81% had basic sanitation services and 78% had basic hygiene facilities.

CONCLUSIONS

This method can generate basic water safety data for a city at a relatively low cost in terms of person-time and materials, yielding useful information for inter-city analyses. Because 29% of samples did not meet microbiological safety criteria, 22% of the households did not have access to handwashing facilities and none had safe sanitation services, we concluded that Cochabamba did not meet normative SDG 6 targets when surveyed. Our study further suggests that water quality at point-of-use more accurately characterizes drinking water safety than infrastructure type.

Impact of the Integration of Water Treatment, Hygiene, Nutrition, and Clean Delivery Interventions on Maternal Health Service Use

AbstractReducing barriers associated with maternal health service use, household water treatment, and improved hygiene is important for maternal and neonatal health outcomes. We surveyed a sample of 201 pregnant women who participated in a clinic-based intervention in Kenya to increase maternal health service use and improve household hygiene and nutrition through the distribution of water treatment products, soap, protein-fortified flour, and clean delivery kits. From multivariable logistic regression analyses, the adjusted odds of ≥ 4 antenatal care (ANC4+) visits (odds ratio [OR] = 3.0, 95% confidence interval [CI] = 1.9-4.5), health facility delivery (OR = 5.3, 95% CI = 3.4-8.3), and any postnatal care visit (OR = 2.8, 95% CI = 1.9-4.2) were higher at follow-up than at baseline, adjusting for demographic factors. Women who completed primary school had higher odds of ANC4+ visits (OR = 1.8, 95% CI = 1.1-2.9) and health facility delivery (OR = 4.2, 95% CI = 2.5-7.1) than women with less education. For women who lived ≤ 2.5 km from the health facility, the estimated odds of health facility delivery (OR = 2.4, 95% CI = 1.5-4.1) and postnatal care visit (OR = 1.6, 95% CI = 1.0-2.6) were higher than for those who lived > 2.5 km away. Compared with baseline, a higher percentage of survey participants at follow-up were able to demonstrate proper handwashing (P = 0.001); water treatment behavior did not change. This evaluation suggested that hygiene, nutritional, clean delivery incentives, higher education level, and geographical contiguity to health facility were associated with increased use of maternal health services by pregnant women.