Global rotavirus strain review shows that while diversity is limited in many settings, reassortment between common and uncommon serotypes leads to unusual diversity in regions like India and Brazil.
The presence of unusual rotavirus strain diversity in certain regions highlights the need for vaccines to account for regional reassortants beyond the 4 common G serotypes.
Candidate rotavirus vaccines have been prepared with reassortant strains specifically to protect against the 4 major rotavirus G serotypes (G1 -4). Many studies using P (VP4) genotyping methods have indicated that, worldwide, rotavirus strains of the 4 common G serotypes are each associated with 1 P genotype: GI, G3, and G4 are associated with P8, and G2 is associated with P4. In contrast, G and P genotyping of rotavirus in specimens from India revealed that a high percentage of the childhood diarrhea strains belong to genotype P6, and the most common strain had an unusual G serotype, G9. Similarly, in all regions surveyed in Brazil, apparent reassortants of genotype P8, G5 were found in children with gastroenteritis. These studies indicate that while rotavirus strains have limited diversity in many settings, reassortment between common and uncommon serotypes or animal strains can arise in some settings and, thus, lead to unusual diversity.
Gentsch et al. (Sun,) conducted a review in Rotavirus infection. Global rotavirus strain review shows that while diversity is limited in many settings, reassortment between common and uncommon serotypes leads to unusual diversity in regions like India and Brazil.