Genome-Wide Evolutionary Analyses of G1P[8] Strains Isolated Before and After Rotavirus Vaccine Introduction.

Rotaviruses are the most important etiological agent of acute gastroenteritis in young children worldwide. Among the first countries to introduce rotavirus vaccines into their national immunization programs were Belgium (November 2006) and Australia (July 2007). Surveillance programs in Belgium (since 1999) and Australia (since 1989) offer the opportunity to perform a detailed comparison of rotavirus strains circulating pre- and postvaccine introduction.

Characterization of G2P[4] rotavirus strains associated with increased detection in Australian states using the RotaTeq® vaccine during the 2010-2011 surveillance period.

The introduction of rotavirus vaccines Rotarix® and RotaTeq® into the Australian National Immunisation Program in July 2007 has resulted in a dramatic decrease in the burden of rotavirus disease. G2P[4] strains became the dominant genotype Australia-wide during the 2010-2011 surveillance period and for the first time since vaccine introduction, a higher proportion were isolated in jurisdictions using RotaTeq® vaccine compared to locations using Rotarix®. Phylogenetic analysis of the VP7 gene of 32 G2P[4] strains identified six genetic clusters, these distinct clusters were also observed in the VP4 gene for a subset of 12 strains.

Identification and characterization of antibody-binding epitopes on the norovirus GII.3 capsid.

Genotype II.3 (GII.3) noroviruses are a major cause of sporadic gastroenteritis, particularly in children.

Selection and evolutionary analysis in the nonstructural protein NSP2 of rotavirus A.

Rotavirus A is the leading cause of acute gastroenteritis in infants and young children worldwide. The nonstructural protein 2 (NSP2) plays essential roles in the replication cycle of rotavirus and may play a role in protective immunity against rotavirus disease. Using a Bayesian approach, we measured the mutation rate of genotype N1 NSP2 gene sequences.

Identification of an antibody-binding epitope on the rotavirus A non-structural protein NSP2 using phage display analysis.

The non-structural protein 2 (NSP2) of rotavirus has important roles in rotavirus replication associated with RNA binding, hydrolysis of NTPs and RNA, and helix destabilizing properties. A cell-culture assay using an NSP2-specific mAb and polyclonal antiserum to block virus replication showed a 73 and 96 % reduction in the amount of virus produced during replication, respectively. Phage display technology was used to identify the antibody-binding region on the NSP2 protein with the motif (244)T-(Y/F)-Ø-Ø-Ø-X-K-Ø-G(252), where Ø is a hydrophilic residue and X is any amino acid.

Phylogenetic analysis of rotavirus A NSP2 gene sequences and evidence of intragenic recombination.

The rotavirus non-structural protein NSP2 is one of the earliest and most abundant viral proteins produced during infection. This protein has multiple essential roles in the replication cycle involving RNA binding, viroplasm formation, helicase and can hydrolyse the γ-phosphate of RNA and NTPs acting as an RTPase and NTPase. In studying sequences from rotavirus strains isolated in Australia between 1984 and 2009, the NSP2 gene was seen to be highly conserved and clustered with defined NSP2 genotypes N1 and N2 according to the full genome based rotavirus classification system.