Nationwide seroprevalence of SARS-CoV-2 during the COVID-19 pandemic and prepandemic periods in Lao PDR.

ABSTRACT:

Background

Lao PDR reported a low number of confirmed SARS-CoV-2 cases until the introduction of COVID-19 vaccines in April 2021. This raised doubts about whether the reported number reflected the true situation and questioned about possible pre-existing immunity against SARS-CoV-2.

Methods

We retrospectively analyzed leftover blood donor samples collected in 2003-2004, 2015, and 2018 in Vientiane Capital, as well as samples collected in 2020 and between February and August 2021 across 18 provinces in Lao PDR to better understand the epidemiology of the infection. The samples were first screened using an anti-SARS-CoV-2 IgG ELISA (Euroimmun). The presence of anti-SARS-CoV-2 antibodies was then confirmed or refuted by testing positive and equivocal samples using anti-SARS-CoV

SUBMITTER: Phommasone K 

PROVIDER: S-EPMC12614595 | biostudies-literature | 2025

REPOSITORIES: biostudies-literature