背景:三价口服脊髓灰质炎病毒疫苗(tOPV)于2016年4月在全球范围内被二价口服脊髓灰质炎病毒疫苗(bOPV)取代(“开关”)。从那时起,已经报道了许多与2型循环疫苗衍生的脊髓灰质炎(cVDPV2)相关的麻痹性脊髓灰质炎暴发。全球根除脊髓灰质炎倡议(GPEI)制定了标准操作程序(SOP),以指导经历cVDPV2疫情的国家实施及时有效的疫情应对(OBR)。为了评估遵守SOP在成功阻止cVDPV2爆发中的可能作用,我们分析了OBR过程中关键时间线的数据.
方法:收集了2016年4月1日至2020年12月31日期间检测到的所有cVDPV2暴发的数据,以及2016年4月1日至2021年12月31日期间对这些暴发的所有暴发响应。我们使用GPEI脊髓灰质炎信息系统数据库进行了二次数据分析,匿名机构脊髓灰质炎病毒实验室的记录,和单价OPV2(mOPV2)咨询小组的会议记录。对于该分析,将循环病毒的通知日期定义为第0天。提取的过程变量与GPEISOP版本3.1中的指标进行了比较。
结果:在2016年4月1日至2020年12月31日期间,报告了由67次不同的cVDPV2暴发引起的111次cVDPV2暴发,影响了四个世界卫生组织地区的34个国家。在第0天之后进行第一次大规模活动(R1)的65个OBR中,只有12个(18.5%)R1在第0天之后通过28天的目标进行。在第0天之后进行第二次大规模活动(R2)的89个OBR中,在第0天之后56天的目标进行30(33.7%)R2。在第0天之后爆发的72次分离株中,有23次(31.9%)在120天的目标内停止。
结论:因为\"交换机\",OBR实施的延误在许多国家都很明显,这可能与cVDPV2爆发的持久性>120天有关。做到及时有效应对,各国应遵循GPEIOBR指南。
Trivalent oral poliovirus vaccine (tOPV) was globally replaced with bivalent oral poliovirus vaccine (bOPV) in April 2016 (\"the switch\"). Many outbreaks of paralytic poliomyelitis associated with type 2 circulating vaccine-derived poliovirus (cVDPV2) have been reported since this time. The Global Polio Eradication Initiative (GPEI) developed standard operating procedures (SOPs) to guide countries experiencing cVDPV2 outbreaks to implement timely and effective outbreak response (OBR). To assess the possible role of compliance with SOPs in successfully stopping cVDPV2 outbreaks, we analyzed data on critical timelines in the OBR process.
Data were collected on all cVDPV2 outbreaks detected for the period April 1, 2016 and December 31, 2020 and all outbreak responses to those outbreaks between April 1, 2016 and December 31, 2021. We conducted secondary data analysis using the GPEI Polio Information System database, records from the U.S. Centers for Disease Control and Prevention Polio Laboratory, and meeting minutes of the monovalent OPV2 (mOPV2) Advisory Group. Date of notification of circulating virus was defined as Day 0 for this analysis. Extracted process variables were compared with indicators in the GPEI SOP version 3.1.
One hundred and eleven cVDPV2 outbreaks resulting from 67 distinct cVDPV2 emergences were reported during April 1, 2016-December 31, 2020, affecting 34 countries across four World Health Organization Regions. Out of 65 OBRs with the first large-scale campaign (R1) conducted after Day 0, only 12 (18.5%) R1s were conducted by the target of 28 days after Day 0. Of the 89 OBRs with the second large-scale campaign (R2) conducted after Day 0, 30 (33.7%) R2s were conducted by the target of 56 days after Day 0. Twenty-three (31.9%) of the 72 outbreaks with isolates dated after Day 0 were stopped within the 120-day target.
Since \"the switch\", delays in OBR implementation were evident in many countries, which may be related to the persistence of cVDPV2 outbreaks >120 days. To achieve timely and effective response, countries should follow GPEI OBR guidelines.