Seroprevalence of antibodies against hepatitis A and E among the general population in 5 provinces, Lao People's Democratic Republic: Variation according to location

PLoS One. 2025 Aug 14;20(8):e0329384. doi: 10.1371/journal.pone.0329384. eCollection 2025.

Abstract

Hepatitis A and E viruses (HAV and HEV) are transmitted through the faecal-oral route: via contaminated food, water, and contact with infected people and/or animals for HEV. Due to limited data from Lao People's Democratic Republic (Lao PDR), we assessed HAV and HEV seroprevalence in the Lao general population. A cross-sectional study collected 2412 serum samples and demographic information from participants (5-93 years) across five provinces. Anti-HAV (IgM and IgG) and anti-HEV antibodies (IgG) were detected by enzyme-linked immunosorbent assay (Dia.Pro). The overall seroprevalence of anti-HAV was 84.3% and anti-HEV was 57.9%. Seropositivity was associated with occupation, location, increasing age, ethnicity (only for anti-HAV) and sex (only for anti-HEV). The age at which 50% of the population was seropositive differed from 12 years (Oudomxay) to 26 years (Savannakhet and Vientiane) for anti-HAV and from 22 years (Savannakhet) to 49 years (Vientiane) for anti-HEV. The prevalence of double seropositivity was high overall (53.4%), particularly in Savannakhet and Champasack. These significant differences according to location and socio-demographics may be the result of variation of exposure to the viruses, such as through water, sanitation and hygiene-related risks, occupational exposure and animal contact. Further studies are warranted to identify the most important risks for transmission in Lao PDR in order to develop targeted public health interventions.

MeSH terms

  • Adolescent
  • Adult
  • Aged
  • Aged, 80 and over
  • Child
  • Child, Preschool
  • Cross-Sectional Studies
  • Female
  • Hepatitis A Antibodies* / blood
  • Hepatitis A virus* / immunology
  • Hepatitis A* / blood
  • Hepatitis A* / epidemiology
  • Hepatitis A* / immunology
  • Hepatitis Antibodies* / blood
  • Hepatitis E virus* / immunology
  • Hepatitis E* / blood
  • Hepatitis E* / epidemiology
  • Hepatitis E* / immunology
  • Humans
  • Immunoglobulin G / blood
  • Laos / epidemiology
  • Male
  • Middle Aged
  • Seroepidemiologic Studies
  • Southeast Asian People
  • Young Adult

Substances

  • Hepatitis A Antibodies
  • Immunoglobulin G
  • Hepatitis Antibodies

Supplementary concepts

  • Laotian people