International Centre for Diarrhoeal Disease Research, Bangladesh (icddr,b), Bangladesh.
International Centre for Diarrhoeal Disease Research, Bangladesh (icddr,b), Bangladesh.
Vaccine. 2020 Feb 29;38 Suppl 1:A127-A131. doi: 10.1016/j.vaccine.2019.06.082. Epub 2019 Jul 10.
Cholera has been endemic in India and Bangladesh for the greater part of recorded history, giving this region the reputation of being the 'homeland of cholera'. The causative organism Vibrio cholerae O1 has been responsible for large epidemics and pandemics. Bangladesh and India have conducted several sequential studies of Oral Cholera Vaccine (OCV) to ascertain its safety, efficacy, effectiveness, field feasibility and acceptance in high-risk urban populations. The objective of this article is to illustrate the experience of OCV use in these endemic settings, its major challenges, and how policymakers can grant vaccine licenses as well as implement its use in the national immunization programme. The relevant aspects of the OCV studies, such as boosting the effect of vaccine, single-dose versus double-dose trials and thermal stability of the vaccine during delivery have generated strong evidence for recommendation of vaccine use in these settings. Studies have shown that a single dose is effective for children of five years of age and older age groups. The locally manufactured vaccine in India is thermostable and can be delivered in field settings without use of cold chain. The vaccine delivery is feasible and the protective efficacy (PE) of this vaccine above five years of age against cholera was 53-65%. Administration of an OCV boosting regimen elicits an immune response similar to those who received a two-dose vaccine five years back. OCV can be used as a preemptive measure in endemic settings, in natural calamities and during political instability when there is total disruption as well as collapse of safe water supply, sanitation and hygiene (WASH) facilities and other control measures. Clear identification of areas and target population (who will gain benefit from the OCVs) is required to be developed in endemic settings.
在有记录历史的大部分时间里，霍乱一直存在于印度和孟加拉国，这使得该地区享有“霍乱之乡”的声誉。致病生物体霍乱弧菌 O1 一直是导致大规模流行和大流行的原因。孟加拉国和印度已经进行了几项口服霍乱疫苗（OCV）的连续研究，以确定其安全性、有效性、效果、现场可行性和在高危城市人群中的可接受性。本文的目的是说明在这些流行地区使用 OCV 的经验、主要挑战，以及政策制定者如何授予疫苗许可证以及在国家免疫规划中实施其使用。OCV 研究的相关方面，如增强疫苗效果、单剂量与双剂量试验以及疫苗在运输过程中的热稳定性，为推荐在这些环境中使用疫苗提供了强有力的证据。研究表明，一剂疫苗对五岁及五岁以上的儿童有效。印度生产的本地疫苗具有热稳定性，无需冷链即可在现场使用。疫苗接种是可行的，这种疫苗对五岁以上人群的保护效力（PE）为 53-65%。接种 OCV 增强剂可引起与五年前接种两剂疫苗相似的免疫反应。在流行地区、自然灾害期间以及在总中断以及安全饮用水供应、卫生和环境卫生（WASH）设施和其他控制措施崩溃的政治不稳定期间，OCV 可作为预防措施使用。需要在流行地区确定明确的地区和目标人群（谁将从 OCV 中受益）。
