Chemoprophylaxis of close contacts and vaccination of high-risk population groups is ongoing.密切接触者的化学预防和高危人群组的预防接种正在进行。
Some influenza viruses develop resistance to the antiviral medicines, limiting the effectiveness of chemoprophylaxis and treatment.一些流感病毒对抗病毒药物产生耐药性，从而降低化学预防和药物治疗的效力。
