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.

Progress Toward Measles Elimination--China,January 2013-June 2019

What is already known about this topic?China has historically had high measles incidence and many associated deaths.A comprehensive measles elimination plan during 2006-2012 substantially reduced measles incidence;however,a resurgence occurred during 2013-2015.What is added by this report?In China,measles surveillance,outbreak response,research,and program evaluation were used to strengthen routine immunization and target immunization activities for eliminating measles.Measles incidence declined from 31 per million in 2015 to 2.8 in 2018;only one measles-associated death has been reported during 2018-June 2019.What are the implications for public health practice?The World Health Organization-recommended strategy to eliminate measles can be effective,including in large,densely populated countries like China.

Vaccine-Associated Paralytic Poliomyelitis--8 PLADs,China,October 2012–March 2014

Introduction:Poliomyelitis is a highly contagious,seasonal viral disease caused by any of three poliovirus(PV)serotypes(types 1,2,or 3).Oral poliovirus vaccine(OPV)on rare occasions causes vaccineassociated paralytic poliomyelitis(VAPP)in recipients of OPV and close contacts of recently vaccinated individuals.This study describes the epidemiology of VAPP when an all OPV schedule was used in the Expanded Program on Immunization(EPI).Methods:VAPP cases were identified using standardized diagnostic criteria from data reported by 8 provincial-level administrative divisions(PLADs)to the National Acute Flaccid Paralysis(AFP)Surveillance System in an 18-month period between October 2012 and March 2014.Results:During this period,28 VAPP cases were reported.Using the number of births as a denominator,the estimated incidence of VAPP was 2.47 cases per million births.Using the number of OPV doses administered through routine immunization,the VAPP incidence was 0.55 cases per million doses.Among vaccine-recipient VAPP cases,22(85%)were associated with the first dose of OPV;3 were associated with the second OPV dose.The relative risk of VAPP following the first dose compared with the second dose was 7.07.Conclusions and Implications for Public Health Practice:The per-dose and per-child incidences of VAPP were consistent with incidence estimates by the World Health Organization(WHO).The vast majority(85%)of VAPP in China was associated with the first dose of OPV in an all-OPV schedule.Because inactivated polio vaccine(IPV)is known to prevent VAPP from subsequent doses of OPV in immunocompetent children,this association provided strong evidence for using an IPV-first,sequential IPVOPV polio vaccination schedule in China during the globally-synchronized cessation of type 2 OPV and introduction of IPV in 2016.