Changing patterns of rotavirus genotypes in ghana:
emergence of human rotavirus G9 as a major cause of diarrhea in children.
Armah GE, Steele AD, Binka FN, Esona MD, Asmah RH, Anto F, Brown D, Green J,
Cutts F, Hall A.
Noguchi Memorial Institute for Medical Research, School of Public Health,
University of Ghana, Legon. garmah@noguchi.mimcom.net
Genotyping of human rotaviruses was performed on 312 rotavirus-positive samples
collected from 2,205 young children with diarrhea in the Upper East District of
Ghana, a rural community. Of the 271 (86.9%) rotavirus strains that could be VP7
(G) or VP4 (P) characterized, 73 (26.9%) were of G9 specificity. The predominant
G9 genotype was G9P[8], which constituted 79.5% of all G9 strains detected,
followed by G9P[6] (12.3%), G9P[10] (2.7%), and G9P[4] (1.3%). G9 strains with
mixed P types constituted 2.7% of all G9 strains found in the study. All the
G9P[8] strains had a long RNA electrophoretic pattern with VP6 subgroup II
specificity. Four G9 isolates, GH1319, GH1416, GH3550, and GH3574, which were
selected based on the abundance of stool material and were representative of the
three electropherotypes observed, were cloned and sequenced. The Ghanaian
isolates shared more than 98% sequence nucleotide homology with other G9 strains
from the United States (US1205), Malawi (MW69), Brazil (R160), Japan (95H115),
and Nigeria (Bulumkutu). However, they showed only 95% nucleotide homology with
the Thai G9 strain Mc345. Phylogenetic analysis of the nucleic acid sequence
revealed the existence of at least three clusters, with Ghanaian strains forming
one cluster, Nigerian and Brazilian strains forming a second cluster, and U.S.,
Malawian, and Japanese strains forming a third.
PMID: 12791843 [PubMed - indexed for MEDLINE]