PDF(Pubmed)
Abstract：
Despite the successful introduction of oral cholera vaccines, Zambia continues to experience multiple, sporadic, and protracted cholera outbreaks in various parts of the country. While vaccines have been useful in staying the cholera outbreaks, the ideal window for re-vaccinating individuals resident in cholera hotspot areas remains unclear. Using a prospective cohort study design, 225 individuals were enrolled and re-vaccinated with two doses of Shanchol™, regardless of previous vaccination, and followed-up for 90 days. Bloods were collected at baseline before re-vaccination, at day 14 prior to second dosing, and subsequently on days 28, 60, and 90. Vibriocidal assay was performed on samples collected at all five time points. Our results showed that anti-LPS and vibriocidal antibody titers increased at day 14 after re-vaccination and decreased gradually at 28, 60, and 90 days across all the groups. Seroconversion rates were generally comparable in all treatment arms. We therefore conclude that vibriocidal antibody titers generated in response to re-vaccination still wane quickly, irrespective of previous vaccination status. However, despite the observed decline, the levels of vibriocidal antibodies remained elevated over baseline values across all groups, an important aspect for Zambia where there is no empirical evidence as to the ideal time for re-vaccination.
摘要：
尽管成功引入了口服霍乱疫苗，赞比亚继续经历多次，零星的,以及该国各地旷日持久的霍乱疫情。虽然疫苗对保持霍乱疫情很有用，霍乱热点地区居民重新接种疫苗的理想窗口仍不清楚.使用前瞻性队列研究设计，225名个体被招募并再次接种了两剂Shanchol™，不管以前的疫苗接种，并随访90天。在重新接种疫苗之前，在基线时收集血液，在第二次给药之前的第14天，随后在第28、60和90天。对在所有五个时间点收集的样品进行杀弧菌测定。我们的结果显示,抗LPS和杀弧菌抗体滴度在再次接种后第14天增加,并且在所有组的第28、60和90天逐渐降低。血清转换率在所有治疗组中通常是相当的。因此，我们得出的结论是，响应于重新接种疫苗而产生的杀弧菌抗体滴度仍然迅速下降，无论以前的疫苗接种情况如何。然而,尽管观察到下降，所有组的杀弧菌抗体水平均高于基线值，对于赞比亚来说，这是一个重要的方面，那里没有经验证据表明再接种疫苗的理想时间。
