Incidence And Molecular Characterization Of Neonatal Human Rotavirus Strains In Accra.

AKWASI AGYEMAN 106 PAGES (18673 WORDS) Biochemistry Thesis

ABSTRACT

Specific and sensitive tests for the detection and typing of rotavirus strains are essential for a more assessment of the epidemiology of rotaviral infection in a community. In this study, 200 stool specimens obtained from October, 1999 to March, 2000 from neonates at the Babies Unit of the Korle-Bu teaching and Legon Hospitals were examined. Group A rotavirus was detected in 30% and Non-group A in 2.5% of the samples tested by either enzyme-linked immunosorbent assay (ELISA) for the detection of VP6 antigen and/ or polyacrylamide gel electrophoresis (PAGE) of double-stranded RNA respectively. Reverse transcription-PCR (RT-PCR) was used for the amplification of the VP7:G (1,062 bp) and VP4:P (876 bp) genes. Five positive specimens were positive by PAGE but negative by ELISA. G and P typing was carried out by nested amplification of variable sequences of the VP7 and the VP4 genes with six G- and five P-type-specific primers (multiplex PCR). The observed P and G types were as follows: G2, 57.1%; G3, 7.1%; G9, 10.7%; G2G3, 3.6%; P6, 67.9%; P8, 3.6%; P6P10, 14.3%. 21.4% of G type and 14.3% of P type were nontypeable. The G-P type combination most frequently found was G2P6 (42.9%), which is the most commonly found in neonates worldwide. Unusual strains of the type G3P6, G9P6 accounted for 7.1% and 3.6% respectively while mixed infections with more than one type were found in 17.9% of the samples typed. Samples whose either P and/ or G could be typed accounted for 28.6%.