title: Epidemiologic features of overseas imported malaria in the People's Republic of China.
abstract: BACKGROUND
  With the dramatic increase in international travel among Chinese people, the risk of malaria importation from malaria-endemic regions threatens the achievement of the malaria elimination goal of China.
  
  
  METHODS
  Epidemiological investigations of all imported malaria cases were conducted in nine provinces of China from 1 Nov, 2013 to 30 Oct, 2014. Plasmodium species, spatiotemporal distribution, clinical severity, preventive measures and infection history of the imported malaria cases were analysed using descriptive statistics.
  
  
  RESULTS
  A total of 1420 imported malaria cases were recorded during the study period, with P. falciparum (723 cases, 50.9 %) and P. vivax (629 cases, 44.3 %) being the two predominant species. Among them, 81.8 % of cases were in Chinese overseas labourers. The imported cases returned from 41 countries, mainly located in Africa (58.9 %) and Southeast Asia (39.4 %). About a quarter (25.5 %, 279/1094) of counties in the nine study provinces were affected by imported malaria cases. There were 112 cases (7.9 %) developing complicated malaria, including 12 deaths (case fatality rate: 0.8 %). Only 27.8 % of the imported cases had taken prophylactic anti-malarial drugs. While staying abroad, 27.7 % of the cases had experienced two or more episodes of malaria infection. The awareness of clinical manifestations and the capacity for malaria diagnosis were weak in private clinics and primary healthcare facilities.
  
  
  CONCLUSIONS
  Imported malaria infections among Chinese labourers, returned from various countries, poses an increasing challenge to the malaria elimination programme in China. The risk of potential re-introduction of malaria into inland malaria-free areas of China should be urgently addressed.
authors.affiliation: Division of Infectious Diseases, Key Laboratory of Surveillance and Early-warning on Infectious Disease, Chinese Center for Disease Control and Prevention, 155 Changbai Road, Changping, 102206, Beijing, China. lizj@chinacdc.cn.
authors.forename: Zhongjie
authors.initials: Z
authors.lastname: Li
authors.affiliation: Division of Infectious Diseases, Key Laboratory of Surveillance and Early-warning on Infectious Disease, Chinese Center for Disease Control and Prevention, 155 Changbai Road, Changping, 102206, Beijing, China. zhangqian@chinacdc.cn.
authors.forename: Qian
authors.initials: Q
authors.lastname: Zhang
authors.affiliation: Division of Infectious Diseases, Key Laboratory of Surveillance and Early-warning on Infectious Disease, Chinese Center for Disease Control and Prevention, 155 Changbai Road, Changping, 102206, Beijing, China. zhengcj@chinacdc.cn.
authors.forename: Canjun
authors.initials: C
authors.lastname: Zheng
authors.affiliation: Division of Infectious Diseases, Key Laboratory of Surveillance and Early-warning on Infectious Disease, Chinese Center for Disease Control and Prevention, 155 Changbai Road, Changping, 102206, Beijing, China. zhousheng@chinacdc.cn.
authors.forename: Sheng
authors.initials: S
authors.lastname: Zhou
authors.affiliation: Division of Infectious Diseases, Key Laboratory of Surveillance and Early-warning on Infectious Disease, Chinese Center for Disease Control and Prevention, 155 Changbai Road, Changping, 102206, Beijing, China. sunjl@chinacdc.cn.
authors.forename: Junling
authors.initials: J
authors.lastname: Sun
authors.affiliation: Division of Infectious Diseases, Key Laboratory of Surveillance and Early-warning on Infectious Disease, Chinese Center for Disease Control and Prevention, 155 Changbai Road, Changping, 102206, Beijing, China. zhangzk1@chinacdc.cn.|Center of Clinical Laboratory, the First Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou, China. zhangzk1@chinacdc.cn.
authors.forename: Zike
authors.initials: Z
authors.lastname: Zhang
authors.affiliation: Division of Infectious Diseases, Key Laboratory of Surveillance and Early-warning on Infectious Disease, Chinese Center for Disease Control and Prevention, 155 Changbai Road, Changping, 102206, Beijing, China. gengqb@chinacdc.cn.|State Key Laboratory of Virology and College of Life Sciences, Wuhan University, Wuhan, China. gengqb@chinacdc.cn.
authors.forename: Qibin
authors.initials: Q
authors.lastname: Geng
authors.affiliation: Division of Infectious Diseases, Key Laboratory of Surveillance and Early-warning on Infectious Disease, Chinese Center for Disease Control and Prevention, 155 Changbai Road, Changping, 102206, Beijing, China. zhanghl@chinacdc.cn.
authors.forename: Honglong
authors.initials: H
authors.lastname: Zhang
authors.affiliation: Division of Infectious Diseases, Key Laboratory of Surveillance and Early-warning on Infectious Disease, Chinese Center for Disease Control and Prevention, 155 Changbai Road, Changping, 102206, Beijing, China. wanglp@chinacdc.cn.
authors.forename: Liping
authors.initials: L
authors.lastname: Wang
authors.affiliation: Division of Infectious Diseases, Key Laboratory of Surveillance and Early-warning on Infectious Disease, Chinese Center for Disease Control and Prevention, 155 Changbai Road, Changping, 102206, Beijing, China. laisj@chinacdc.cn.|Department of Geography and Environment, University of Southampton, Southampton, UK. laisj@chinacdc.cn.
authors.forename: Shengjie
authors.initials: S
authors.lastname: Lai
authors.affiliation: School of Public Health and Social Work, Queensland University of Technology, Brisbane, Australia. w2.hu@qut.edu.au.
authors.forename: Wenbiao
authors.initials: W
authors.lastname: Hu
authors.affiliation: Research School of Population Health, College of Medicine, Biology and Environment, The Australian National University, Canberra, Australia. director.rsph@anu.edu.au.
authors.forename: Archie C A
authors.initials: AC
authors.lastname: Clements
authors.affiliation: National Institute of Parasitic Diseases, Chinese Center for Disease Control and Prevention, Key Laboratory of Parasite and Vector Biology, MOH, WHO Collaborating Centre for Tropic Diseases, National Center for International Research on Tropical Diseases, 207 Rui Jin Er Road, Shanghai, 200025, People's Republic of China. ipdzhouxn@sh163.net.
authors.forename: Xiao-Nong
authors.initials: XN
authors.lastname: Zhou
authors.affiliation: Key Laboratory of Surveillance and Early-warning on Infectious Disease, Chinese Center for Disease Control and Prevention, Beijing, China. yangwz@chinacdc.cn.
authors.forename: Weizhong
authors.initials: W
authors.lastname: Yang
mesh_terms: D000328:Adult; D000349:Africa / Q000453:epidemiology; D001210:Asia, Southeastern / Q000453:epidemiology; D002681:China / Q000208:ethnology; D005260:Female; D006801:Humans; D008288:Malaria / Q000453:epidemiology* / Q000208:ethnology* / Q000517:prevention & control; D008297:Male; D008875:Middle Aged; D055815:Young Adult