Enhanced surveillance of acute flaccid paralysis following importation of wild poliovirus in Xinjiang Uygur Autonomous Region, China
1 Chinese Center for Disease Control and Prevention, 27 Nanwei Rd, Xicheng District, Beijing 100050, PR China
2 The Center for Disease Control and Prevention of the Xinjiang Production and Construction Corps, 344 Wuxingnanlu Street, Urumqi city, Xinjiang Uygur autonomous region 830002, PR China
3 Expanded Programme on Immunization, Xinjiang Uygur autonomous region Center for Disease Control and Prevention, 138 Jianquanyi Street, Urumqi city, Xinjiang Uygur autonomous region 830001, PR China
4 WHO WPRO Regional Polio Reference Laboratory, National Institute for Viral Disease Control and Prevention, Chinese Center for Disease Control and Prevention, 155 Changbai Rd, Changping District, Beijing 102206, PR China
5 Independent Consultant, New York City, NY, USA
BMC Infectious Diseases 2014, 14:113 doi:10.1186/1471-2334-14-113Published: 27 February 2014
After being polio free for more than 10 years, an outbreak occurred in China in 2011 in Xinjiang Uygur Autonomous Region (Xinjiang) following the importation of wild poliovirus (WPV) originating from neighboring Pakistan.
To strengthen acute flaccid paralysis (AFP) surveillance in Xinjiang, “zero case daily reporting” and retrospective searching of AFP cases were initiated after the confirmation of the WPV outbreak. To pinpoint all the polio cases in time, AFP surveillance system was expanded to include persons of all ages in the entire population in Xinjiang.
Totally, 578 AFP cases were reported in 2011 in Xinjiang, including 21 WPV cases, 23 clinical compatible polio cases and 534 non-polio AFP cases. Of the 44 polio cases, 27 (61.4%) cases were reported among adults aged 15–53 years. Strengthening AFP surveillance resulted in an increase in the number of non-polio AFP cases in 2011 (148 children < 15 years) compared with 76 cases < 15 years in 2010. The AFP surveillance system in Xinjiang was sensitive enough to detect polio cases, with the AFP incidence of 3.28/100,000 among children < 15 years of age.
Incorporating adult cases into the AFP surveillance system is of potential value to understand the overall characteristics of the epidemic and to guide emergency responses, especially in countries facing WPV outbreak following long-term polio free status. The AFP surveillance system in Xinjiang was satisfactory despite limitations in biological sample collection.