Pre-vaccine circulating group a rotavirus strains in under 5 years children with acute diarrhea during 1999-2013 in Cameroon.

The aim of this review was to assess all the studies on rotavirus G and P characterization during the pre-vaccine period (1999-2013) in Cameroon to have a better basis for post-vaccine introduction evaluations. A retrospective study was done through a comprehensive review of published (PubMed, Google Scholar) and accessible unpublished data on rotavirus G and P genotypes circulating in five regions of Cameroon. Descriptive data were expressed as frequencies tables and proportions. A total of 1844 rotavirus positive cases were analyzed. In all, 1534 strains were characterized for the P (VP4) specificity. Six different VP4 genotypes were observed, including P [4], P [6], P [8], P [9], P [10] and P [14]. The most predominant P genotypes were P [8] at 42.6%, and P [6] at 37.9%. Mixed infections were observed at 5.3%, whereas 4.1% of the strains were P non-typeable. A total of 1518 rotavirus strains were characterized for the G (VP7) specificity. VP7 genotypes G1, G2, G3, G4, G5, G6, G8, G9, G10 and G12 were observed. G1 (35.3%), G3 (19.5%), G2 (14.9%) and G12 (10.1%) were the predominant G genotypes while G5 and G10 were least prevalent at 0.06% each. Approximately 5.1% of all strains were G non-typeable whereas 5.3% were mixed G genotypes. A total of 1472 strains were characterized for both G and P genes, from which 38 different G-P combinations were observed. Overall, G1P [8] (22%) was identified as the predominant rotavirus strain circulating in Cameroon followed by G3P [6] (15%). In conclusion, we observed that the genotypes identified in Cameroon during 1999-2013 were partially covered by the two WHO recommended rotavirus vaccines. This review provides comprehensive up-to-date information on rotavirus strain surveillance in Cameroon during the pre-vaccination era.