关于流感疫苗
Each year, the World Health Organization recommends an influenza vaccine that includes three strains of influenza virus (two of type A and one of type B) based on the strains that were circulating worldwide during the previous flu seasons in the Southern and Northern Hemispheres. The vaccine is then produced for the next flu season.
Because influenza is a serious disease that results in both excess mortality and serious economic losses, many countries provide routine annual vaccination against influenza. The vaccine is recommended especially for elderly persons and persons with underlying chronic illness.
Due to cost and limited production globally, however, the vaccine is generally not available in developing countries.
If travelling to the Southern or Northern hemisphere during that area’s winter season when flu viruses are actively circulating, travellers should obtain this vaccine before they depart if possible.
时间表
The flu vaccine is administered in one dose and must be repeated yearly since the vaccine changes to adjust to changes in the viruses.
副作用
流感疫苗通常耐受良好，很少出现严重问题。轻度副作用可能包括注射时出现的酸痛，发红或肿胀，轻度发烧，嗓子痛，肌肉酸痛，头痛，瘙痒和疲劳。对鸡蛋或蛋制品过敏的人不应服用此疫苗，因为它们可能会产生严重的过敏反应。
