In 2020 Lao PDR had low reported COVID-19 cases but it was unclear whether this masked silent transmission. A seroprevalence study was done August - September 2020 to determine SARS-CoV-2 exposure.
Siriphone Virachith, Virginie Pommelet, Elodie Calvez, Vilaysone Khounvisith, Somphou Sayasone, et al.. Low seroprevalence of COVID-19 in Lao PDR, late 2020. The Lancet Regional Health - Western Pacific, 2021, 13, pp.100197. ⟨10.1016/j.lanwpc.2021.100197⟩. ⟨pasteur-03661224⟩