Seroepidemiology of Predominant Norovirus Strains Circulating in Korea by Using Recombinant Virus-Like Particle Antigens

Abstract

An epidemiological survey on human norovirus (NoV)–associated gastroenteritis was conducted to clarify the prevalence of NoV infections in children and adults in Korea. Recombinant capsid proteins from three major NoV genotypes (GI-4, GII-3, and GII-4) were expressed using a baculovirus expression system, and the morphology and antigenicity of self-assembled virus-like particles were then confirmed by electron microscopy and Western blotting with a NoV-specific antibody. To determine seroprevalence, an enzyme-linked immunosorbent assay was performed to detect antibodies against virus-like particles antigen in 346 serum specimens collected from persons who visited five public heath care centers for regular physical examination in Jeollanam-do, Korea, between 2005 and 2006. The seroprevalence of immunoglobulin G antibodies against the GI-4, GII-3, and GII-4 NoV genotypes was 84.1%, 76.3%, and 94.5%, respectively. A rapid decrease in seroprevalence occurred after birth, with the lowest levels observed in the <23-month age group, and a steep increase in seroprevalence occurred in early childhood, reaching 60.5% for GI-4, 65.1% for GII-3, and 90.7% for GII-4 at age 2–5 years, and over 80% for all three genotypes in subjects aged 20 years or older. The seroprevalence of different NoV genotypes statistically differed across the age groups (p<0.01).