Molecular epidemiology of group A human rotaviruses in North West region, Cameroon

Abstract

Background: Rotavirus (RV) is the most common cause of severe diarrhea in children <5 years of age worldwide accounting for 527,000 deaths
annually. Over 80% of these deaths occur in South Asia and sub-Saharan Africa. RV vaccines have significantly reduced RV-associated morbidity
and mortalities in several countries like the United States and Mexico while vaccine trials have proved efficacious in Ghana and other developing
countries. However, there is paucity of data on RV infection in Cameroon where diarrhea is a major childhood disease.

Methods: A total of 534 stool specimens collected between January 2003 and December 2004 from children with acute gastroenteritis in five health districts in the NWR of Cameroon were screened for group A human rotavirus antigen by ELISA and their electropherotypes determined by Polyacrylamide gel electrophoresis.

Results: RV was detected in 153 (28.7%) diarrheic specimens with infection occurring throughout the year, being more common
in children under two years of age (P < 0.01) with the highest incidence in the 7-9 months age group (P <0.05). Sub clinical infections (9%)
occurred mostly in children aged 0 - 6 months old (P<0.01). Source of drinking water was not associated with RV infection. Eleven
electropherotype patterns were detected with predominance of long electropherotypes (92.8%) and mixed electropherotypes were seen only in
hospitalized children. Some isolates showed overlapping or merged genome segments 7 and 8 or 9 and presenting with 10 segments of the RV genome.

Conclusion: RV is a significant cause of pediatric diarrhea in the NWR affecting mostly children under 2 years of age. Continuous RV
surveillance and nationwide surveys are recommended to improve the health of young children in Cameroon. More research is needed to fully
characterize the isolated RV strains.

Key words: Rotavirus, diarrhea, molecular epidemiology, electropherotypes