Immunogenicity of Oxford-AstraZeneca COVID-19 vaccine in Vietnamese healthcare workers by Van Vinh Chau, N, Nguyet, LA, Truong, NT, Toan, LM, Dung, NT, Hung, LM, Nhan, MT, Huy Man, DN, Ngoc, NM, Thao, HP, Hoang Tu, TN, Mai, HK, Hung, DT, Han Ny, NT, Thanh, LK, Anh, NT, Thu Hong, NT, Truc Nhu, LN, Yen, LM, Choisy, M, Thanh, TT, Thwaites, G, Van Tan, L