Environmental surveillance of surface contamination is an unexplored tool for understanding transmission of SARS-CoV-2 in community settings. We conducted longitudinal swab sampling of high-touch non-porous surfaces in a Massachusetts town during a COVID-19 outbreak from April to June 2020. Twenty-nine of 348 (8.3%) surface samples were positive for SARS-CoV-2 RNA, including crosswalk buttons, trash can handles, and door handles of essential business entrances (grocery store, liquor store, bank, and gas station). The estimated risk of infection from touching a contaminated surface was low (less than 5 in 10,000) by quantitative microbial risk assessment, suggesting fomites play a minimal role in SARS-CoV-2 community transmission. The weekly percentage of positive samples (out of n = 33 unique surfaces per week) best predicted variation in city-level COVID-19 cases with a 7-day lead time. Environmental surveillance of SARS-CoV-2 RNA on high-touch surfaces may be a useful tool to provide early warning of COVID-19 case trends.

Environmental surveillance of surface contamination is an unexplored tool for understanding transmission of SARS-CoV-2 in community settings. We conducted longitudinal swab sampling of high-touch non-porous surfaces in a Massachusetts town during a COVID-19 outbreak from April to June 2020. Twenty-nine of 348 (8.3 %) surface samples were positive for SARS-CoV-2, including crosswalk buttons, trash can handles, and door handles of essential business entrances (grocery store, liquor store, bank, and gas station). The estimated risk of infection from touching a contaminated surface was low (less than 5 in 10,000), suggesting fomites play a minimal role in SARS-CoV-2 community transmission. The weekly percentage of positive samples (out of n=33 unique surfaces per week) best predicted variation in city-level COVID-19 cases using a 7-day lead time. Environmental surveillance of SARS-CoV-2 RNA on high-touch surfaces could be a useful tool to provide early warning of COVID-19 case trends.

Financially sustainable strategies are needed to increase access to safe drinking water in low-income settings. We designed a novel in-line chlorine doser that employs the Venturi principle to automatically add liquid chlorine at the point of water collection (tap outflows). The Venturi does not require electricity or moving parts, and users do not have to change the way they typically collect water. We field-tested the Venturi and assessed its technical performance and sales viability at water kiosks in Kisumu County, Kenya. We offered kiosk owners 6-month service packages to lease or lease-to-own the device; 27% of kiosks given a sales pitch committed to a service package. All but one kiosk paid in full during the 6-month service period and more than two-thirds purchased the device with payments totaling >$250 USD per kiosk. Kiosk customers could choose to purchase chlorinated or unchlorinated water from separate taps; 66% reported buying chlorinated water. Kiosk taps fitted with the Venturi had detectable free chlorine residual 97.6% of the time. The technical performance of the Venturi and effective demand from kiosks indicate high potential for the Venturi to increase safe water access in low-income communities.

Climate change may impact human health through the influence of weather on environmental transmission of diarrhea. Previous studies have found that high temperatures and heavy precipitation are associated with increased diarrhea prevalence, but the underlying causal mechanisms are not clear. We linked measurements of Escherichia coli in source water (n=1,673), stored drinking water (n=8,924), and hand rinses from children <2 years old (n=2,660) with publicly available gridded temperature and precipitation data (at ≤0.2 degree spatial resolution and daily temporal resolution) by the GPS coordinates and date of sample collection. Measurements were collected over a 3-year period across a 2500 km2 area in rural Kenya. In drinking water sources, high 7-day temperature was associated with a 0.16 increase in log10 E. coli levels (p<0.001), while heavy 7-day total precipitation was associated with a 0.29 increase in log10 E. coli levels (p<0.001). In household stored drinking water, heavy 7-day precipitation was associated with a 0.079 increase in log10 E. coli levels (p=0.042). On child hands, high 7-day temperature was associated with a 0.39 decrease in log10 E. coli levels (p<0.001). Our findings provide insight on how climate change could impact environmental transmission of bacterial pathogens in Kenya, and suggest water treatment could be a mitigation strategy.

Climate change may impact human health through the influence of weather on environmental transmission of diarrhea. Previous studies have found that high temperatures and heavy precipitation are associated with increased diarrhea prevalence, but the underlying causal mechanisms have not been tested and validated. We linked measurements of Escherichia coli in source water (n = 1673), stored drinking water (n = 9692), and hand rinses from children <2 years old (n = 2634) with publicly available gridded temperature and precipitation data (at ≤0.2 degree spatial resolution and daily temporal resolution) by the GPS coordinates and date of sample collection. Measurements were collected over a 3-year period across a 2500 km2 area in rural Kenya. In drinking water sources, high 7-day temperature was associated with a 0.16 increase in log10 E. coli levels (p < 0.001, 95% CI: 0.07, 0.24), while heavy 7-day total precipitation was associated with a 0.29 increase in log10 E. coli levels (p < 0.001, 95% CI: 0.13, 0.44). In household stored drinking water, heavy 7-day precipitation was associated with a 0.079 increase in log10 E. coli levels (p = 0.042, 95% CI: 0.07, 0.24). Heavy precipitation did not increase E. coli levels among respondents who treated their water, suggesting that water treatment can mitigate effects on water quality. On child hands, high 7-day temperature was associated with a 0.39 decrease in log10 E. coli levels (p < 0.001, 95% CI: −0.52, −0.27). Our findings provide insight on how climate change could impact environmental transmission of bacterial pathogens in Kenya. We suggest water treatment is especially important after heavy precipitation (particularly when preceded by dry periods) and high temperatures.