SEVERE PROGNOSTIC FACTORS OF POST-VACCINATION REACTIONS IN CHILDREN UNDER 5 YEARS AT VIET NAM NATIONAL CHILDREN’S HOSPITAL. YHCĐ [Internet]. 2026 June 11 [cited 2026 Sept. 9];66(Vol 67. English Version No 2). Available from: https://tapchiyhcd.vn/index.php/yhcd/article/view/4081