Monitoring poliovirus among acute flaccid paralysis cases and in environmental sewage during 2016-2023 in Heilongjiang province
Objective To monitor poliovirus among acute flaccid paralysis(AFP)cases and in environmental sewage and confirm polio-free status in Heilongjiang province.Methods We obtained stool samples from reported AFP cases＜15 years old and sewage samples from environmental monitoring sites during 2016-2023.We isolated enteroviruses(EV),including polioviruses(PV)and non-polio enteroviruses(NPEV);determined PV serotypes;and conducted intratypic differentiation.Results The average annual reported incidence of AFP cases＜15 years old was 1.95 per 100 000 population(613 cases)during 2016-2023 in Heilongjiang.EVs,PVs,and NPEVs were isolated from 3.10％(19 cases),0.49％(3 cases),and 2.61％(16 cases)of AFP cases,respectively.Four PV isolates from AFP cases were vaccine-like strains:2 type Ⅲ and 2 type Ⅰ+Ⅲ.EVs,PVs,and NPEVs were isolated from 74.75％(222 specimens),43.43％(129 specimens),and 57.91％(172 specimens)of 297 environmental sewage specimens;313 PV isolates from environmental sewage included 45,6,and 262 type Ⅰ,type Ⅱ,and type Ⅲ strains,in which one strain was identified as a type Ⅱ VDPV(in July 2016)and others were vaccine-like strains.Conclusion Most PV isolates were vaccine-like strains,and no wild poliovirus were found among AFP cases or in environmental sewage during 2016-2013 in Heilongjiang,indicating continuous maintenance of polio-free status.
万方数据
维普
