Antigenic and Genetic Characterization of Serotype G2 Human Rotavirus Strains from the African Continent

Abstract

Serotype G2 rotavirus strains were isolated in seven countries on the African continent during 1999 and 2000. To investigate the associated DS-1 genogroup characteristics, subgroup (VP6) enzyme-linked immunosorbent assay, polyacrylamide gel electrophoresis, and P genotyping were performed on 10 G2 strains. The antigenic and genetic variation of the gene encoding the major neutralization glycoprotein (VP7) was also investigated by using G2-specific monoclonal antibodies and sequence analysis. Alterations in the characteristic DS-1 genogroup gene constellations were more likely to occur in the VP4 gene, and three genotypes were observed: P[4], P[6], and a dual P[4]-P[6] type. The failure of G2-specific monoclonal antibodies to type African G2 strains was more likely due to improper storage of the original stool, although G2 monotypes were detected. Phylogenetic analyses revealed clusters of serotype G2 strains that were more commonly associated with seasons during which G2 was predominant. No rotavirus vaccine trials have been conducted in an area where G2 strains were the predominant circulating serotype, and the continued surveillance of rotavirus epidemics in Africa will be preparation for future vaccine implementation in an area that clearly needs these preventative medicines.

G2 rotavirus infections in an infantile population of the South of Italy: Variability of viral strains over time

“…Iturriza-Gòmara et al [2001] attributed the loss of reactivity of some G2 strains with the specific MAbs S2-2G10, RV5:3, and IC10 to the same substitution at aa 96. However, Page and Steele [2004b] described a G2 strain from Burkina Faso displaying the same aa changes as the British 1996 isolates that reacted with both S2-2G10 and IC10 anti-G2 MAbs.…”

“…Monotype 2b strains were originally considered to be more likely to cause localized outbreaks [Page and Steele, 2004b], but in Palermo lineage III G2 strains were recovered from sporadic cases of infantile gastroenteritis over a 2-year G2 peak. The 2003 G2 epidemic was caused in Palermo by strains that were different in both their VP7 and VP4 sequences from those circulating in Palermo in 1996-1997.…”

“…In Europe, epidemiological studies reported low circulation rates for G2 serotype [Bon et al, 2000;Buesa et al, 2000;Iturriza-Gòmara et al, 2001;Ehlken et al, 2002;Santos and Hoshino, 2005] and little information is at present available on the antigenic or genetic variability of rotaviruses with such type specificity [Zao et al, 1999;Iturriza-Gòmara et al, 2001;Page and Steele, 2004a]. Lack of reactivity with the G2-specific monoclonal antibodies (MAbs) of rotavirus strains has been reported in many occasions [Ward et al, 1991;Unicomb et al, 1999;Iturriza-Gòmara et al, 2001;Page and Steele, 2004b].…”

G8Rotavirus Strains Isolated in the Democratic Republic of Congo Belong to the DS-1-Like Genogroup

“…4A). HRVs with DS-1-like features and the G2P [6] specificity were detected in 1997 in Brazil and South Africa (37,50) and since then were found on several occasions on the African continent (in Ghana, Nigeria, Burkina Faso, and Guinea-Bissau) (3,7,46,50). The P [6] specificity of these DS-1 like HRVs presumably arose after one or more reassortment events involving DS-1-like HRVs and RVs with the P[6] specificity (Fig.…”

Rotavirus G2P[4] and G2P[4]+[6] infections during norovirus gastroenteritis outbreak: summer season 2010, Brazil

“…In Nigeria, a G2 RV strain displaying dual P [4] and P [6] The inclusion of alternative P types in serotype G2 strain gene constellations may provide a means of escaping protective immunity and generating increased RV diversity 12 . Uncommon associations could also be related to reassortment between cocirculating RV strains 15 .…”