Addo Isaac Yeboah, Dadzie Frederick Asankom, Okeke Sylvester Reuben, Boadi Caleb, Boadu Elijah Frimpong
Centre for Social Research in Health, University of New South Wales, Sydney, 2052, Australia.
Centre for Ecosystem Science, School of Biological, Earth and Environmental Sciences, University of New South Wales, Sydney, 2052, Australia.
Arch Public Health. 2022 Sep 2;80(1):200. doi: 10.1186/s13690-022-00935-x.
As vaccine roll-out continues across the globe as part of the efforts to protect humanity against SARS-CoV-2, concerns are increasingly shifting to the duration of vaccine-induced immunity. Responses to these concerns are critical in determining if, when, and who will need booster doses following full vaccination against SARS-CoV-2. However, synthesised studies about the durability of vaccine-induced immunity against SARS-CoV-2 are scarce. This systematic review synthesised available global evidence on the duration of immunity following full vaccination against SARS-CoV-2.
We searched through Psych Info, Web of Science, Scopus, Google Scholar, PubMed, and WHO COVID-19 databases for relevant studies published before December 2021. Five eligibility criteria were used in scrutinising studies for inclusion. The quality of the included studies was assessed based on Joana Briggs Institute's (JBI) Critical Appraisal tool and Cochrane's Risk of Bias tool-version 2 (RoB 2), while the reporting of the results was guided by the Synthesis Without Meta-analysis (SWiM) guidelines.
Twenty-seven out of the 666 identified studies met the inclusion criteria. The findings showed that vaccine-induced protection against SARS-CoV-2 infections builds rapidly after the first dose of vaccines and peaks within 4 to 42 days after the second dose, before waning begins in subsequent months, typically from 3 to 24 weeks. Vaccine-induced antibody response levels varied across different demographic and population characteristics and were higher in people who reported no underlying health conditions compared to those with immunosuppressed conditions.
Waning of immunity against SARS-CoV-2 begins as early as the first month after full vaccination and this decline continues till the sixth month when the level of immunity may not be able to provide adequate protection against SARS-CoV-2. While the evidence synthesised in this review could effectively inform and shape vaccine policies regarding the administration of booster doses, more evidence, especially clinical trials, are still needed to ascertain, with greater precision, the exact duration of immunity offered by different vaccine types, across diverse population characteristics, and in different vulnerability parameters.
The protocol for this review was pre-registered with the International Prospective Register of Systematic Reviews [PROSPERO] (Registration ID: CRD420212818).
作为全球保护人类免受严重急性呼吸综合征冠状病毒2（SARS-CoV-2）侵害努力的一部分，疫苗接种工作仍在持续推进，人们日益关注疫苗诱导免疫的持续时间。应对这些担忧对于确定在完成SARS-CoV-2全程疫苗接种后是否、何时以及哪些人需要接种加强针至关重要。然而，关于疫苗诱导针对SARS-CoV-2免疫持久性的综合研究很少。本系统评价综合了全球范围内关于SARS-CoV-2全程疫苗接种后免疫持续时间的现有证据。
我们在PsycINFO、科学网、Scopus、谷歌学术、PubMed和世界卫生组织COVID-19数据库中检索了2021年12月之前发表的相关研究。在筛选纳入研究时使用了五条纳入标准。纳入研究的质量根据乔安娜·布里格斯研究所（JBI）的批判性评价工具和Cochrane偏倚风险工具第2版（RoB 2）进行评估，而结果报告则以非Meta分析的综合（SWiM）指南为指导。
在666项已识别的研究中，有27项符合纳入标准。研究结果表明，疫苗诱导的针对SARS-CoV-2感染的保护作用在首剂疫苗接种后迅速建立，并在第二剂疫苗接种后4至42天内达到峰值，随后在接下来的几个月中开始下降，通常从3至24周开始。疫苗诱导的抗体反应水平因不同的人口统计学和人群特征而异，与免疫功能低下的人群相比，报告无基础健康状况的人群抗体反应水平更高。
针对SARS-CoV-2的免疫减弱在全程疫苗接种后的第一个月就开始了，这种下降会持续到第六个月，此时免疫水平可能无法为抵御SARS-CoV-2提供足够的保护。虽然本综述中综合的证据可以有效地为有关加强针接种的疫苗政策提供信息并塑造相关政策，但仍需要更多证据，尤其是临床试验，以更精确地确定不同疫苗类型在不同人群特征和不同易感性参数下提供的免疫的确切持续时间。
本综述方案已在国际前瞻性系统评价注册库[PROSPERO]（注册号：CRD420212818）进行了预注册。
