Etiologies, Risk Factors and Impact of Severe Diarrhea in the Under-Fives in Moramanga and Antananarivo, Madagascar.

Background: Diarrheal disease remains a leading cause of death in children in low-income countries. We investigated the etiology, risk factors and effects on nutritional status of severe diarrhea in children from two districts in Madagascar.

Methods: We performed a matched case-control study in 2011 to 2014, on children under the age of five years from Moramanga and Antananarivo. The cases were children hospitalized for severe diarrhea and the controls were children without diarrhea selected at random from the community. Stool samples were collected from both groups. Anthropometric measurements were made during follow-up visits about one and two months after enrolment.

Results: We enrolled 199 cases and 199 controls. Rotavirus infection was the most frequently detected cause of diarrhea. It was strongly associated with severe diarrhea (OR: 58.3; 95% CI: 7.7-439.9), accounting for 42.4% (95% CI: 37.6-43.1) of severe diarrhea cases. At the household level, possession of cattle (OR = 0.3; 95% CI: 0.1-0.6) and living in a house with electricity (OR = 0.4; 95% CI: 0.2-0.8) were protective factors. The presence of garbage around the house was a risk factor for severe diarrhea (OR = 3.2; 95% CI: 1.9-5.4). We found no significant association between severe diarrhea and the nutritional status of the children at follow-up visits, but evident wasting at enrolment was associated with a higher risk of severe diarrhea (OR = 9; 95% CI: 4.5-17.9).

Conclusions: Severe childhood diarrhea is mostly caused by rotavirus infection. An anti-rotavirus vaccine has already been introduced in Madagascar and should be promoted more widely. However, post-licensing surveillance is required. Interventions to improve the nutritional status of children, preventive measures focused on household and personal hygiene and nutritional rehabilitation during severe diarrheal disease should be reinforced.