玉林市急性弛缓性麻痹病例肠道病毒感染状况分析

Analysis on Enterovirus Infections of Acute Flaccid Paralysis Cases in Yulin

目的了解玉林市急性弛缓性麻痹(AFP)病例肠道病毒感染及其流行病学情况,为制订维持无脊灰状态AFP监测策略提供科学依据。方法运用流行病学分析方法对玉林市1996～2004年AFP病例中粪便检测到肠道病毒(EV)病例进行分类,分析其免疫史、性别、年龄与病原学结果之间的关系。结果1996～2004年共检测了251例急性弛缓性麻痹病例的粪便标本,分离到肠道病毒55株,分离率为21.91%。包括脊髓灰质炎病毒(PV)14株,均为疫苗相关株,其中Ⅱ型7株,占50%;口服脊灰减毒活疫苗“零”剂次免疫AFP病例的PV分离率依次高于1～2次和≥3次免疫者,分别为20.00%、17.86%和3.40%。PV感染引起残留麻痹6例,其中Ⅱ型4例。口服脊灰减毒活疫苗“零”剂次免疫的PV感染病例残留麻痹率依次高于1～2次和≥3次免疫者。非脊灰肠道病毒(NPEV)41株,NPEV检出农村高于城区。结论玉林市巳连续12年未发现由脊灰野病毒引起的病例。在无脊灰证实以后,应加强对PV和NPEV的研究,特别是本文中脊灰疫苗株病毒对0剂次免疫儿童的致病和致残率高于全程免疫者的原因有待进一步探讨,今后我们应继续抓好常规免疫,提高免疫接种率,消除免疫空白。

Objective This study was designed to understand enterovirus infections and their epidemiological characteristics of acute flaccid paralysis （AFP） cases in Yulin city to provide a scientific evidence for the formulation of AFP surveillance strategies on the maintenance of poliomyelitis eradication. Methods Epidemiological analysis was used to classify the AFP cases in whom enteroviruses were detected in their faces from 1996 to 2004 in Yulin city, and the relationship between their immunization history, genders and ages, and etiology was analyzed Results Fecal samples of 251 cases of AFP were tested from 1996 through 2004 and 55 strains of enteroviruses were isolated with an isolation rate of 21.91%. Of the isolated, there were 14 poliomyelitis viruses （PV） which were vaccine-related strains, including 7 strains of type Ⅱ viruses （50%）; The isolation rate of PV in cases of AFP with no immunization of oral attenuated live polio vaccine was higher than that of those immunized once to twice and higher than or equal to that of those immunized three times for the disease, with the rate being 20.00%, 17.86% and 3.40%, respectively. Niteen cases of EV infection menifested residual paralysis 60 days after the onset of the disease. And residual paralysis was seen in six cases of PV infection, four of whom were of type Ⅱ, accounting for 66.67%. The residual paralysis rate was higher in the cases of PV infection with zero oral polio-virus vaccine immunization than in those with 1 to 2 immunizations and still higher than in those with 3 or more immunizations. Also, 41 strains of non-poliomyelitis enteroviruses （NPEV） were detected with the incidence higher in rural areas than in towns. Conclusion There have been no cases found caused by wild poliomyelitis viruses for 12 years in Yulin city. After polio eradication having been confirmed, the study on PV and NPEV is to be strengthened, and especially the causes of the morbidity and disability rate of children with no immunization of poliovirus vaccines being both higher than those of fully immunized children remain to be learned. We should henceforth keep on reinforcing the routine immunization schedule, enhancing the rate of vaccination and eradicating zero immunization.