title: Transmission dynamics, border entry screening, and school holidays during the 2009 influenza A (H1N1) pandemic, China.
abstract: Pandemic influenza A (H1N1) 2009 virus spread rapidly around the world in 2009. We used multiple data sources from surveillance systems and specific investigations to characterize the transmission patterns of this virus in China during May-November 2009 and analyze the effectiveness of border entry screening and holiday-related school closures on transmission. In China, age distribution and transmission dynamic characteristics were similar to those in Northern Hemisphere temperate countries. The epidemic was focused in children, with an effective reproduction number of ≈1.2-1.3. The 8 days of national holidays in October reduced the effective reproduction number by 37% (95% credible interval 28%-45%) and increased underreporting by ≈20%-30%. Border entry screening detected at most 37% of international travel-related cases, with most (89%) persons identified as having fever at time of entry. These findings suggest that border entry screening was unlikely to have delayed spread in China by >4 days.
authors.affiliation: Chinese Center for Disease Control and Prevention, Beijing, People’s Republic of China.
authors.forename: Hongjie
authors.initials: H
authors.lastname: Yu
authors.forename: Simon
authors.initials: S
authors.lastname: Cauchemez
authors.forename: Christl A
authors.initials: CA
authors.lastname: Donnelly
authors.forename: Lei
authors.initials: L
authors.lastname: Zhou
authors.forename: Luzhao
authors.initials: L
authors.lastname: Feng
authors.forename: Nijuan
authors.initials: N
authors.lastname: Xiang
authors.forename: Jiandong
authors.initials: J
authors.lastname: Zheng
authors.forename: Min
authors.initials: M
authors.lastname: Ye
authors.forename: Yang
authors.initials: Y
authors.lastname: Huai
authors.forename: Qiaohong
authors.initials: Q
authors.lastname: Liao
authors.forename: Zhibin
authors.initials: Z
authors.lastname: Peng
authors.forename: Yunxia
authors.initials: Y
authors.lastname: Feng
authors.forename: Hui
authors.initials: H
authors.lastname: Jiang
authors.forename: Weizhong
authors.initials: W
authors.lastname: Yang
authors.forename: Yu
authors.initials: Y
authors.lastname: Wang
authors.forename: Neil M
authors.initials: NM
authors.lastname: Ferguson
authors.forename: Zijian
authors.initials: Z
authors.lastname: Feng
mesh_terms: D002681:China / Q000453:epidemiology; D054242:Emigrants and Immigrants; D006693:Holidays; D006801:Humans; D015994:Incidence; D055256:Infectious Disease Incubation Period; D053118:Influenza A Virus, H1N1 Subtype; D007251:Influenza, Human / Q000453:epidemiology* / Q000517:prevention & control / Q000635:transmission*; D058873:Pandemics; D011159:Population Surveillance; D012574:Schools; D014195:Travel