TY - JOUR
T1 - Multiple pathogen contamination of water, hands, and fomites in rural Nepal and the effect of WaSH interventions
AU - Uprety, Sital
AU - Ngo, Isaac
AU - Maggos, Marika
AU - Dangol, Bipin
AU - Sherchan, Samendra P.
AU - Shisler, Joanna L.
AU - Amarasiri, Mohan
AU - Sano, Daisuke
AU - Nguyen, Thanh H.
N1 - The study was supported by National Science Foundation Graduate Research Fellowship (GRFP), Japan Society for Promotion of Sciences ( JSPS ) Strategic Fellowship, and National Science Foundation International Research Experience for Students ( NSF-IRES # 1559530 ). The authors thank Mrs. Pramina Nakarmi, Ishal Dhakal of Enpho, University of Illinois undergraduate students Alex Celmer, Preeti Naraynan and Hannah Nolton who assisted with sampling and DNA extraction and Mr. Yashimitsu Konta of Tohoku University for his invaluable support in laboratory analysis. The authors also thank Rebecca Lee Smith for the invaluable guidance in data analysis and interpretation.
PY - 2024/4
Y1 - 2024/4
N2 - Water, Sanitation, and Hygiene (WaSH) interventions are the most effective in reducing diarrheal disease severity and prevalence. However, very few studies have investigated the effectiveness of WaSH intervention in reducing pathogen presence and concentration. In this study, we employed a microfluidic PCR approach to quantify twenty bacterial pathogens in water (n = 360), hands (n = 180), and fomite (n = 540) samples collected in rural households of Nepal to assess the pathogen exposures and the effect of WaSH intervention on contamination and exposure rates. The pathogen load and the exposure pathways for each pathogen in intervention and control villages were compared to understand the effects of WaSH intervention. Pathogens were detected in higher frequency and concentration from fomites samples, toilet handle (21.42%; 5.4,0 95%CI: mean log10 of 4.69, 5.96), utensils (23.5%; 5.47, 95%CI: mean log10 of 4.77, 6.77), and water vessels (22.42%; 5.53, 95%CI: mean log10 of 4.79, 6.60) as compared to cleaning water (14.36%; 5.05, 95%CI: mean log10 of 4.36, 5.89), drinking water (14.26%; 4.37, 85%CI: mean log10 of 4.37, 5.87), and hand rinse samples (16.92%; 5.49, 95%CI: mean log10 of 4.77, 6.39). There was no clear evidence that WaSH intervention reduced overall pathogen contamination in any tested pathway. However, we observed a significant reduction (p < 0.05) in the prevalence, but not concentration, of some target pathogens, including Enterococcus spp. in the intervention village compared to the control village for water and hands rinse samples. Conversely, no significant reduction in target pathogen concentration was observed for water and hand rinse samples. In swab samples, there was a reduction mostly in pathogen concentration rather than pathogen prevalence, highlighting that a reduction in pathogen prevalence was not always accompanied by a reduction in pathogen concentration. This study provides an understanding of WaSH intervention on microbe concentrations. Such data could help with better planning of intervention activities in the future.
AB - Water, Sanitation, and Hygiene (WaSH) interventions are the most effective in reducing diarrheal disease severity and prevalence. However, very few studies have investigated the effectiveness of WaSH intervention in reducing pathogen presence and concentration. In this study, we employed a microfluidic PCR approach to quantify twenty bacterial pathogens in water (n = 360), hands (n = 180), and fomite (n = 540) samples collected in rural households of Nepal to assess the pathogen exposures and the effect of WaSH intervention on contamination and exposure rates. The pathogen load and the exposure pathways for each pathogen in intervention and control villages were compared to understand the effects of WaSH intervention. Pathogens were detected in higher frequency and concentration from fomites samples, toilet handle (21.42%; 5.4,0 95%CI: mean log10 of 4.69, 5.96), utensils (23.5%; 5.47, 95%CI: mean log10 of 4.77, 6.77), and water vessels (22.42%; 5.53, 95%CI: mean log10 of 4.79, 6.60) as compared to cleaning water (14.36%; 5.05, 95%CI: mean log10 of 4.36, 5.89), drinking water (14.26%; 4.37, 85%CI: mean log10 of 4.37, 5.87), and hand rinse samples (16.92%; 5.49, 95%CI: mean log10 of 4.77, 6.39). There was no clear evidence that WaSH intervention reduced overall pathogen contamination in any tested pathway. However, we observed a significant reduction (p < 0.05) in the prevalence, but not concentration, of some target pathogens, including Enterococcus spp. in the intervention village compared to the control village for water and hands rinse samples. Conversely, no significant reduction in target pathogen concentration was observed for water and hand rinse samples. In swab samples, there was a reduction mostly in pathogen concentration rather than pathogen prevalence, highlighting that a reduction in pathogen prevalence was not always accompanied by a reduction in pathogen concentration. This study provides an understanding of WaSH intervention on microbe concentrations. Such data could help with better planning of intervention activities in the future.
KW - Fomites
KW - Intervention
KW - Nepal
KW - Pathogen
KW - WaSH
KW - qPCR
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U2 - 10.1016/j.ijheh.2024.114341
DO - 10.1016/j.ijheh.2024.114341
M3 - Review article
C2 - 38442666
AN - SCOPUS:85186353865
SN - 1438-4639
VL - 257
JO - International Journal of Hygiene and Environmental Health
JF - International Journal of Hygiene and Environmental Health
M1 - 114341
ER -