Etiology of Diarrhea among Severely Malnourished Infants and Young Children: Observation of Urban-Rural Differences over One Decade in Bangladesh

There is inadequate information on the etiology of diarrhea in severely malnourished (SM) young children. Thus, the study aimed to determine the etiology of diarrhea among severely malnourished (z score < −3.00 SD) children in rural and urban Bangladesh. From the database (2000-2011) of Diarrheal Disease Surveillance Systems (DDSS) at rural Matlab and urban Dhaka hospitals of icddr,b, 2234 and 3109 under-5 children were found severely malnourished (underweight, stunted or wasted) respectively. Two comparison groups [moderately malnourished (MM) and well-nourished (WN)] were randomly selected in a ratio of 1:1:1. Children with all categories of SM were more likely to be infected with Vibrio cholerae (rural—11%; urban—15%), Shigella (16%; 9%), Salmonella (1%; 2%) and Campylobacter (3%; 4%); and less likely to have rotavirus (25%; 20%) compared to only one SM category. Isolation rate of Vibrio cholerae was significantly higher among SM both in rural and urban children (7%; 13%) than those of MM (5%; 10%) and WN (2%; 8%) and lower for rotavirus (30%; 31%), (34%; 43%), (35%; 47%) respectively (p < 0.01). However, for Shigella it was only higher among rural SM children (11%) [MM (9%), and WN (8%) (p < 0.01)]. The isolation rate of Salmonella in SM (2%) was similar to that in MM (2%; p = 0.72) but significantly higher than that in WN (1%; p < 0.01) among urban children. Isolation rates of bacterial enteric pathogens were higher but rotavirus was lower in SM children in both rural and urban area with geographical heterogeneity.