- Jarquin, Claudia;
- Arnold, Benjamin F;
- Muñoz, Fredy;
- Lopez, Beatriz;
- Cuéllar, Victoria M;
- Thornton, Andrew;
- Patel, Jaymin;
- Reyes, Lisette;
- Roy, Sharon L;
- Bryan, Joe P;
- McCracken, John P;
- Colford, John M
Poor sanitation could pose greater risk for enteric pathogen transmission at higher human population densities because of greater potential for pathogens to infect new hosts through environmentally mediated and person-to-person transmission. We hypothesized that incidence and prevalence of diarrhea, enteric protozoans, and soil-transmitted helminth infections would be higher in high-population-density areas compared with low-population-density areas, and that poor sanitation would pose greater risk for these enteric infections at high density compared with low density. We tested our hypotheses using 6 years of clinic-based diarrhea surveillance (2007-2013) including 4,360 geolocated diarrhea cases tested for 13 pathogens and a 2010 cross-sectional survey that measured environmental exposures from 204 households (920 people) and tested 701 stool specimens for enteric parasites. We found that population density was not a key determinant of enteric infection nor a strong effect modifier of risk posed by poor household sanitation in this setting.