Seroprevalence of antibodies to hepatitis A, B and C viruses across all age groups in Chonburi Province, Thailand, 2022-2023

Viral hepatitis is a global challenge, particularly in low- and middle-income countries. The World Health Organization aims to eliminate HBV and HCV by 2030, targeting HBsAg prevalence below 0.1% in children under 5. This study analyzed sera from 1,459 participants of all ages in Chonburi province, Thailand, between October 2022 and January 2023 to assess whether this target has been met and to evaluate the seroprevalence of anti-HBs, anti-HBc, anti-hepatitis A virus (HAV), and anti-HCV in this population. Participants were healthy individuals with no immunosuppressed status. Results indicated a 0% HBsAg seroprevalence rate among children under 5, while those born before the universal immunization program had a seroprevalence rate of 5.6%. The lowest rate of anti-HBs seropositivity (anti-HBs >= 10 mIU/mL) was observed among adolescents aged 11-20 (31.7%). The anti-HBc seropositivity rate increased with age, following a pattern similar to HBsAg trends. Only a small percentage of subjects (0.3%) tested positive for anti-HCV. The seroprevalence of anti-HAV was below 20% in individuals under 40. These findings suggest that Thailand has met the regional HBsAg seroprevalence targets for children under 5 due to high HepB vaccination coverage and timely birth doses.