What is the Potential Cause for the Predominance of GII.2[P16] Norovirus in Acute Gastroenteritis Outbreaks in China?

Abstract

GII.2[P16] noroviruses (NoV) reemerged and rapidly became the main epidemic strain in acute gastroenteritis (AGE) outbreaks in Asian countries since 2016. The current GII.2 [P16] NoV showed the same antigenicity to the ones before 2016, but several unique amino acid substitutions existed in the RNA dependent RNA polymerase (RdRp) and other nonstructural proteins, and the viral load of the current GII.2[P16] NoV was higher than those of other genotypes, it was estimated that the viral replication ability may have improved. However, other genotypes, such as GII.1 and GII.3, also had recombination with the novel RdRp, were not prevalent in AGE-outbreaks; thus, it was inferred that the capsid proteins also played an important role in the enhanced replication process. The viral infection could also be affected by other factors, such as the population genetic background, the climate and environment, and people's lifestyles. Continued surveillance on genetic diversity and evolutionary pattern for the GII.2[P16] NoV is necessary. Potential Factor for the Reemergence of GII.2[P16] in ChinaThough the GII.2 genotype has been reported since the 1970s, it was only detected in sporadic cases and accounted for less than 2% of all NoV genotypes. GII.2[P16] recombinant NoV first appeared in Japan China CDC Weekly Chinese Center for Disease Control and Prevention CCDC Weekly / Vol. 4 / No. 2 27

Innovative nonthermal technologies for inactivation of emerging foodborne viruses

“…Among those known to infect humans (GI, GII, and GIV), GII is one of the most prevalent species in humans (Ogunsakin et al., 2022). Although strain GII.4 showed the highest incidence rate worldwide from 1990 to 2014 (Yu, 2022), GII.2 and GII.17 have been predominant strains in Asian countries, and epidemiological evidence suggests that GII.17 could be the dominant strain to replace GII.4 as the dominant strain based on epidemiological evidence (Ogunsakin et al., 2022).…”