Effects of an urban sanitation intervention on childhood enteric infection and diarrhea in Maputo, Mozambique: A controlled before-and-after trial

Abstract

We conducted a controlled before-and-after trial to evaluate the impact of an onsite urban sanitation intervention on the prevalence of enteric infection, soil transmitted helminth re-infection, and diarrhea among children in Maputo, Mozambique. A non-governmental organization replaced existing poor-quality latrines with pour-flush toilets with septic tanks serving household clusters. We enrolled children aged 1-48 months at baseline and measured outcomes before and 12 and 24 months after the intervention, with concurrent measurement among children in a comparable control arm. Despite nearly exclusive use, we found no evidence that intervention affected the prevalence of any measured outcome after 12 or 24 months of exposure. Among children born into study sites after intervention, we observed a reduced prevalence of Trichuris and Shigella infection relative to the same age group at baseline (<2 years old). Protection from birth may be important to reduce exposure to and infection with enteric pathogens in this setting.

Using path analysis to test theory of change: a quantitative process evaluation of the MapSan trial

“…A small negative effect on handwashing (soap residue) was observed. Abbreviations: 'chefe', chefe de composto (informal compound leader); HWF, handwashing facility; HWWS, handwashing with soap compounds in this study had fewer residents, due in larger part to significant out-migration in the study area in the period since compound selection (2015) [28]. Among intervention compounds, improvements were made to intermediary outcomes of latrine cleanliness, maintenance and privacylatrine 'quality'but not to handwashing behaviour as indicated by soap residue.…”

“…Children aged between 29 days and 48 months were enrolled at baseline (pre-intervention) [26]. Further details of eligibility and enrolment are available [26,28,29].…”

Impacts of an urban sanitation intervention on fecal indicators and the prevalence of human fecal contamination in Mozambique

“…The intervention impact on fecal contamination was evaluated using a controlled beforeand-after (CBA) study design. 5,43 Intervention compounds were enrolled immediately before the new latrine was opened for use, with concurrent enrollment of control compounds conducted at a similar frequency (Table S1). Follow-up visits to each compound were conducted approximately 12 months following baseline enrollment.…”

“…We administered compound-, household-, and childlevel surveys during both baseline and follow-up visits, as described elsewhere. 5,42 Concurrent with survey administration during May -August 2015, we opportunistically collected environmental samples at a subset of MapSan study compounds from the shared outdoor space and from each household with children participating in the health study (see Supporting Information [SI]). During the 12-month follow-up phase in June -September 2016, we revisited the original subset of compounds and collected environmental samples from additional study compounds not sampled at baseline, as time permitted.…”

“…[2][3][4] Recent evaluations of a range of WASH interventions found inconsistent and largely negligible impacts on child diarrhea, growth, and enteric infection. [5][6][7][8][9][10][11][12] Notably, combined interventions did not provide greater protection than their constituent interventions alone, suggesting that key sources of pathogens and pathways of exposure are inadequately addressed by conventional WASH strategies. 6,7,9,[13][14][15] Characterizing fecal contamination in potential exposure pathways may help explain why specific interventions do or do not improve health by identifying which pathways the intervention interrupts and which remain unaffected.…”