Kanungo Suman, Kim Deok Ryun, Haldar Bisakha, Snider Cynthia, Nalavade Uma, Kim Soon Ae, Park Ju Yeon, Sinha Anuradha, Mallick Aiyel Haque, Manna Byomkesh, Sur Dipika, Nandy Ranjan Kumar, Deshpande Jagadish M, Czerkinsky Cecil, Wierzba Thomas F, Petri William A, Ali Mohammad, Dey Ayan
National Institute of Cholera and Enteric Diseases, Kolkata, India.
International Vaccine Institute, Seoul, South Korea.
Heliyon. 2017 Jan 9;3(1):e00223. doi: 10.1016/j.heliyon.2016.e00223. eCollection 2017 Jan.
The final endgame strategy of global polio eradication initiative includes switching from trivalent oral poliovirus vaccines (tOPV) to bivalent oral polio vaccine (bOPV), and introduction of inactivated poliovirus vaccine (IPV). This study compares IPV with tOPV week 39 boost in Indian infants.
Starting 28 March 2012, we enrolled 372 Indian infant-mother pairs from Kolkata, India in an open-label, block-randomized, controlled trial comparing a 39 week tOPV to an IPV boost among infants immunized with three doses of tOPV. The primary outcome was mucosal immunity to poliovirus as measured by fecal polio virus shedding after OPV challenge. The secondary outcome was humoral response as defined by >1:8 titers for neutralizing antibodies at week 40. Seroconversion was measured by change in level of antibody titers from week 18 to week 40. The analyses were performed by both intention-to-treat (ITT) and per-protocol (PP) comparing the occurrences of outcomes between the arms of the study.
Both the study arms provided equivalent mucosal immunity at 52 weeks with a total shedding prevalence of 28%. Vaccination with IPV resulted in significantly higher seroconversion rates for Polio type 2 (p = 0.03) and Polio type 3 (p < 0.01).
This study indicates that an IPV boost at week 39 is equivalent to tOPV in intestinal immunity, and provides higher seroconversion compared to tOPV. The major limitation of the study was the additional OPV doses receive by infants during pulse polio immunization resulted in additional mucosal boosting, diminishing the impact of IPV or tOPV boost at week 39. However, IPV for OPV boost should prove to be a step forward in the global polio eradication initiative to reduce the problem of circulating vaccine-derived poliovirus (cVDPV).
全球根除脊髓灰质炎行动的最终战略包括从三价口服脊髓灰质炎疫苗（tOPV）转换为二价口服脊髓灰质炎疫苗（bOPV），并引入灭活脊髓灰质炎疫苗（IPV）。本研究比较了IPV与tOPV对印度婴儿的39周龄加强免疫效果。
从2012年3月28日开始，我们在印度加尔各答招募了372对婴儿-母亲，进行一项开放标签、区组随机对照试验，比较39周龄时tOPV与IPV加强免疫对已接种三剂tOPV的婴儿的效果。主要结局是口服脊髓灰质炎疫苗激发后通过粪便脊髓灰质炎病毒排出量衡量的对脊髓灰质炎病毒的黏膜免疫。次要结局是40周龄时中和抗体滴度>1:8定义的体液反应。血清阳转通过18周龄至40周龄抗体滴度水平的变化来衡量。分析采用意向性分析（ITT）和符合方案分析（PP），比较研究组间结局的发生情况。
两个研究组在52周时提供了相当的黏膜免疫，总排出率为28%。接种IPV导致2型脊髓灰质炎（p = 0.03）和3型脊髓灰质炎（p < 0.01）的血清阳转率显著更高。
本研究表明，39周龄时的IPV加强免疫在肠道免疫方面与tOPV相当，且与tOPV相比血清阳转率更高。该研究的主要局限性是婴儿在脊髓灰质炎强化免疫期间额外接种的OPV剂量导致额外的黏膜加强免疫，削弱了39周龄时IPV或tOPV加强免疫的效果。然而，IPV用于OPV加强免疫应被证明是全球根除脊髓灰质炎行动中减少循环疫苗衍生脊髓灰质炎病毒（cVDPV）问题的一个进步。
