Cases of Residual Paralysis in an Acute Flaccid Paralysis Surveillance System - China, 2001-2010.

Background: China has been polio-free since 2000 and maintains an acute flaccid paralysis (AFP) surveillance system. Residual paralysis (RP) in children with acute flaccid paralysis can be caused by Sabinstrain poliovirus (PV) and non-polio enteroviruses (NPEV). Methods: The national AFP surveillance data was analyzed to describe AFP cases with RP in the mainland of China during 2001 to 2010. Epidemiological patterns and virus detection of AFP cases with RP were described. Results: Annual incidence of AFP with RP among children aged <15 years old ranged between 0.22-0.35 cases per 100,000. The peak age for AFP with RP and PV was 2 to 4 months. Among cases with viral Sabinstrain viral isolates, types II and III were the most common. A summer season peak in RP cases was similar to cases with NPEV isolated. Conclusions and Implications for Public Health Practice: The first ten years after polio eradication of AFP surveillance data for the occurrence of RP can serve as a baseline rate for poliovirus vaccine changes in the routine immunization system to help detect vaccine safety signals in a timely manner and to support the routine polio immunization program switch in China.