G and P Types of Circulating Rotavirus Strains in the United States during 1996–2005: Nine Years of Prevaccine Data

Abstract

Almost 85% of strains during 1996-2005 had either a G or P antigen that is present in both RotaTeq (Merck) and Rotarix (GlaxoSmithKline). Monitoring of strains after introduction of rotavirus vaccines is important.

Rotavirus infections in Detroit, USA, a region of low vaccine prevalence

“…that the most prevalent genotype combinations in our community were G1P [8] (21.4 %), which is included in both vaccines, followed by G9P [8] (20.4 %), G4P [8] (13 %) which is included in one of the two vaccines and G9P [6] (8.8 %) [1]. Although G9 was the most prevalent G type at 39.5 %, P [8], which is in both vaccines, was the most prevalent P type [1] in the early time period.…”

“…G1 was found in 50/68 (73.5 %) of stool samples, while G9 was found in 20 (29.4 %). P [8] was found in 54 (79.4 %) stool samples. Similar proportions of RV genotypes were found among vaccinated and unvaccinated children.…”

“…RotaTeq (Merck) is a pentavalent humanbovine reassortant vaccine that contains G1, G2, G3 and G4 combined with P[8], the most common P type. Rotarix (GlaxoSmithKline) contains only G1P [8]. Replacement of RVV serotypes with others has been observed with G5 becoming more prevalent in South America, and P[6] being detected in more than half of symptomatic infections in Africa, and suggestions that G9 may be emerging as the most common G type world wide [6,15,19,20].…”

“…Our local data suggest that 5 years after the introduction of RVV there has been no genotype replacement. Although a small increase in G9P [6] [7,8,14]. The number of infections has decreased markedly since the introduction of two live rotavirus vaccines (RVV).…”

“…Although G9 was the most prevalent G type at 39.5 %, P [8], which is in both vaccines, was the most prevalent P type [1] in the early time period. There was a sharp drop in the number of children who presented to our hospital with RV gastroenteritis during 2010 (49 RV-positive cases), however, the number increased to 238 cases in 2011.…”