[1]Chinese Acad Med Sci & Peking Union Med Coll, Sch Populat Med & Publ Hlth, Beijing, Peoples R China.
[2]State Key Lab Resp Hlth & Multimorbid, Beijing, Peoples R China.
[3]Peking Union Med Coll, Key Lab Pathogen Infect Prevent & Control, Minist Educ, Beijing, Peoples R China.
[4]Chinese Acad Med Sci, China Japan Friendship Hosp, Ctr Resp Med, Natl Ctr Resp Dis,State Key Lab Resp Hlth & Multim, Beijing, Peoples R China.
[5]Chinese Acad Med Sci, Beijing Hosp, Natl Ctr Gerontol, Dept Pulm & Crit Care Med,Inst Geriatr Med, Beijing, Peoples R China.
[6]Capital Med Univ, Beijing Pediat Res Inst Beijing Childrens Hosp Nat, Chinese Acad Med Sci, Beijing Key Lab Pediat Resp Infect Dis,Key Lab Maj, Beijing, Peoples R China.
[7]Chinese Ctr Dis Control & Prevent, Beijing, Peoples R China.
[8]Peking Univ, Hlth Sci Ctr, Weifang Joint Res Ctr Maternal & Child Hlth, Sch Publ Hlth,Key Lab Epidemiol Major Dis,Minist E, Beijing, Peoples R China.