Detection and characterization of rotaviruses in hospitalized neonates in Blantyre, Malawi

Abstract

In five separate fecal collections spanning three years, group A rotaviruses were detected by enzyme-linked immunosorbent assay in 35 (25%) of 142 specimens obtained from nondiarrheic, hospitalized neonates in Blantyre, Malawi. Molecular characterization of each strain identified, for the first time in neonates, a short electropherotype, genotype P[6], G8 strain type, similar to the dominant, cocirculating community strain detected in symptomatic infants in Blantyre. Partial sequence analysis of the VP4 and NSP4 genes of neonatal and community strains failed to identify changes which could explain the differences in clinical outcome. Neonatal serotype G8 rotaviruses should be considered as potential rotavirus vaccine candidates for use in Malawi.

FIG. 1.

Multiplex RT-PCR typing of five representative Malawian neonatal rotavirus strains. RT-PCR type-specific products were resolved on a 2% agarose gel and stained with ethidium bromide. Lane 1, 123-bp DNA ladder (GIBCO-BRL, Long Island, N.Y.). Molecular weights are indicated to the left. Lanes 2 to 7, G typing. Second-amplification RT-PCR products of known serotype G1 control strain (lane 2) and Malawian neonatal strains (serotype G8, lanes 3 to 7) are shown. Lanes 8 to 13, P-typing. Second-amplification RT-PCR products of known genotype P[8] control strain (lane 8) and Malawian neonatal strains (genotype P[6], lanes 9 to 13) are shown. The first-amplification con2/con3 products are indicated (arrow).