This study aimed to describe the epidemiology of rotavirus infections in Mozambique before vaccine introduction. Between February 2012 and September 2013, stool specimens, demographic and clinical data were collected from 384 children <5 years old hospitalized with acute diarrhea in Mavalane General Hospital and Manhiça District Hospital, southern Mozambique. The samples were tested for rotavirus A using enzyme-linked immunosorbent assay. The overall prevalence of rotavirus infection was 42.4% [95% confidence interval (95CI): 37.4-47.6%], and was similar in Manhiça (44.3%; 95CI: 36.2-52.7%) and Mavalane (41.3%; 95CI: 34.9-47.9%). The highest prevalence of rotavirus infection was observed in children between 6 and 11 months old. It was also observed that 162 (43.7%) of the children were underweight (weight-for-age z-score < -2), of which 61 were infected by rotavirus.

In Mozambique rotavirus (RV) was shown to be the greatest cause of acute diarrhoea in infants from 0 to 11 months, and in 2015, national rotavirus vaccination was introduced. As with other developing countries, there is very limited active strain characterisation. Rotavirus positive clinical specimens, collected between 2012 and 2013, have now provided information on the genotypes circulating in southern Mozambique prior to vaccine introduction. Genotypes G2 (32.4%), G12 (28.0%), P[4] (41.4%) and P[6] (22.9%) (n = 157) strains were commonly detected with G2P[4] (42.3%) RVs being predominant, specifically during 2013. Phylogenetic evaluation of the VP7 and VP8* encoding genes showed, for the majority of the Mozambican strains, that they clustered with other African strains based on genotype. RVA/Human-wt/MOZ/0153/2013/G2P[4], RVA/Human-wt/MOZ/0308/2012/G2P[4] and RVA/Human-wt/MOZ/0288/2012/G12P[8] formed separate clusters from the other Mozambican strains with similar genotypes, suggesting possible reassortment. Amino acid substitutions in selected epitope regions also supported phylogenetic clustering. As expected, the VP7 and VP8* genes from the Mozambican strains differed from both the RotaTeq® (SC2-9) G2P[5] and Rotarix® (A41CB052A) G1P[8] genes. This study provides information on the genetic diversity of rotavirus strains prior to vaccine introduction and generates baseline data for future monitoring of any changes in rotavirus strains in response to vaccine pressure.Electronic supplementary materialThe online version of this article (doi:10.1007/s00705-017-3575-y) contains supplementary material, which is available to authorized users.

No abstract