VU, Trang Thu et al. Within-household SARS-CoV-2 transmission and vaccine effectiveness in the first three COVID-19 school outbreaks in northern Viet Nam, September–December 2021. Western Pacific Surveillance and Response, Manila, Philippines, v. 15, n. 3, 2024. DOI: 10.5365/wpsar.2024.15.3.1077. Disponível em: https://ojs.wpro.who.int/ojs/index.php/wpsar/article/view/1077. Acesso em: 3 jun. 2026.