Lack of airborne transmission during outbreak of pandemic (H1N1) 2009 among tour group members, China, June 2009.
During June 2-8, 2009, an outbreak of influenza A pandemic (H1N1) 2009 occurred among 31 members of a tour group in China. To identify the mode of transmission and risk factors, we conducted a retrospective cohort investigation. The index case-patient was a female tourist from the United States. Secondary cases developed in 9 (30%) tour group members who had talked with the index case-patient and in 1 airline passenger (not a tour group member) who had sat within 2 rows of her. None of the 14 tour group members who had not talked with the index case-patient became ill. This outbreak was apparently caused by droplet transmission during coughing or talking. That airborne transmission was not a factor is supported by lack of secondary cases among fellow bus and air travelers. Our findings highlight the need to prevent transmission by droplets and fomites during a pandemic.
Han
Ke
K
Chinese Center for Disease Control and Prevention, Beijing, People's Republic of China.
Zhu
Xiaoping
X
He
Fan
F
Liu
Lunguang
L
Zhang
Lijie
L
Ma
Huilai
H
Tang
Xinyu
X
Huang
Ting
T
Zeng
Guang
G
Zhu
Bao Ping
BP
D000328:Adult; D000401:Aircraft; D002681:China / Q000453:epidemiology; D004196:Disease Outbreaks; D005260:Female; D006801:Humans; D053118:Influenza A Virus, H1N1 Subtype; D007251:Influenza, Human / Q000453:epidemiology / Q000635:transmission* / Q000821:virology*; D008297:Male; D018986:Motor Vehicles; D012189:Retrospective Studies; D014195:Travel