WHO Collaborating Centre for Infectious Disease Epidemiology and Control, School of Public Health, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Hong Kong Special Administrative Region, China.
WHO Collaborating Centre for Infectious Disease Epidemiology and Control, School of Public Health, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Hong Kong Special Administrative Region, China.
Lancet Infect Dis. 2022 Oct;22(10):1435-1443. doi: 10.1016/S1473-3099(22)00345-0. Epub 2022 Jul 15.
Hong Kong maintained low circulation of SARS-CoV-2 until a major community epidemic of the omicron (B.1.1.529) sublineage BA.2 began in January, 2022. Both mRNA (BNT162b2 [Fosun Pharma-BioNTech]) and inactivated CoronaVac (Sinovac, Beijing, China) vaccines are widely available; however, vaccination coverage has been low, particularly in older adults aged 70 years or older. We aimed to assess vaccine effectiveness in this predominantly infection-naive population.
In this observational study, we used individual-level case data on mild or moderate, severe or fatal, and fatal disease in patients hospitalised with COVID-19 along with census information and coverage data of BNT162b2 and CoronaVac. We used a negative binomial model, adjusting for age, sex, and calendar day to estimate vaccine effectiveness of one, two, and three doses of both BNT162b2 and CoronaVac vaccines, and relative effectiveness by number of doses and vaccine type.
Between Dec 31, 2020, and March 16, 2022, 13·2 million vaccine doses were administered in Hong Kong's 7·4-million population. We analysed data from confirmed cases with mild or moderate (n=5566), severe or fatal (n=8875), and fatal (n=6866) COVID-19. Two doses of either vaccine protected against severe disease and death within 28 days of a positive test, with higher effectiveness among adults aged 60 years or older with BNT162b2 (vaccine effectiveness 89·3% [95% CI 86·6-91·6]) compared with CoronaVac (69·9% [64·4-74·6]). Three doses of either vaccine offered very high levels of protection against severe or fatal outcomes (97·9% [97·3-98·4]).
Third doses of either BNT162b2 or CoronaVac provide substantial additional protection against severe COVID-19 and should be prioritised, particularly in older adults older than 60 years and others in high-risk populations who received CoronaVac primary schedules. Longer follow-up is needed to assess duration of protection across different vaccine platforms and schedules.
COVID-19 Vaccines Evaluation Program, Chinese Center for Disease Control and Prevention.
香港的 SARS-CoV-2 循环量一直很低，直到 2022 年 1 月，奥密克戎（B.1.1.529）亚谱系 BA.2 开始在社区大规模流行。mRNA（BNT162b2[复星医药-辉瑞]）和灭活 CoronaVac（北京科兴）疫苗广泛可用；然而，疫苗接种率一直很低，特别是在 70 岁及以上的老年人中。我们旨在评估这一主要为感染初治人群的疫苗有效性。
在这项观察性研究中，我们使用了 COVID-19 住院患者轻度或中度、重度或致命和致命疾病的个体水平病例数据，以及人口普查信息和 BNT162b2 和 CoronaVac 的覆盖数据。我们使用负二项模型，根据年龄、性别和日历日调整，以估计 BNT162b2 和 CoronaVac 疫苗一剂、两剂和三剂的疫苗有效性，并根据疫苗类型和剂量数估计相对有效性。
2020 年 12 月 31 日至 2022 年 3 月 16 日期间，香港 740 万人口中接种了 1320 万剂疫苗。我们分析了确诊为轻度或中度（n=5566）、重度或致命（n=8875）和致命（n=6866）COVID-19 的患者的数据。两剂任一疫苗均能在阳性检测后 28 天内预防重症疾病和死亡，60 岁及以上人群中 BNT162b2 疫苗的有效性更高（疫苗有效性 89.3%[95%CI86.6-91.6%]），而 CoronaVac 疫苗为 69.9%[64.4-74.6%]。两剂任一种疫苗对严重或致命结局的保护率均非常高（97.9%[97.3-98.4%]）。
两剂任一种 BNT162b2 或 CoronaVac 疫苗都能为预防严重 COVID-19 提供实质性的额外保护，应优先考虑接种，特别是在 60 岁以上的老年人和其他接受 CoronaVac 基础接种方案的高危人群中。需要更长时间的随访来评估不同疫苗平台和接种方案的保护持续时间。
中国疾病预防控制中心 COVID-19 疫苗评估计划。
