Dear Editor,Avian influenza A (H9N2) virus plays a crucial role in interspecies transmission between animals and humans due to its wide host range, adaptation in mammals and the diversified gene reassortments. Since 1...Dear Editor,Avian influenza A (H9N2) virus plays a crucial role in interspecies transmission between animals and humans due to its wide host range, adaptation in mammals and the diversified gene reassortments. Since 1990s, two lineages of H9N2 virus, A/Duck/HK/Y280/97 (Y280-like)and A/Quail/HK/G1/97 (G1) have established in domestic poultry in China and are now widespread in the展开更多
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 ...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.展开更多
基金supported by the National Natural Science Foundation of China-Youth Scientist Program (Epidemiological spatial-temporal dynamics of H1N1 influenza virus in a climatologically diverse region, 81502856)
文摘Dear Editor,Avian influenza A (H9N2) virus plays a crucial role in interspecies transmission between animals and humans due to its wide host range, adaptation in mammals and the diversified gene reassortments. Since 1990s, two lineages of H9N2 virus, A/Duck/HK/Y280/97 (Y280-like)and A/Quail/HK/G1/97 (G1) have established in domestic poultry in China and are now widespread in the
文摘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.
