Infectious Disease Control and Vaccinations Unit, Department of Health Security, Finnish Institute for Health and Welfare (THL), Helsinki, Finland.
Population Health Unit, Department of Public Health and Welfare, Finnish Institute for Health and Welfare (THL), Tampere, Finland.
PLoS One. 2021 Nov 18;16(11):e0258704. doi: 10.1371/journal.pone.0258704. eCollection 2021.
In Finland, both mRNA and adenovirus vector (AdV) Covid-19 vaccines have been used after the vaccination campaign started on December 27, 2020. Vaccination of the elderly and chronically ill was prioritized and the interval between doses set to 12 weeks. The objective of this interim analysis was to evaluate first and second dose vaccine effectiveness (VE) in a real-world setting.
During the first five months of the campaign, a register-based cohort study was conducted in the Finnish elderly aged 70+ years and those aged 16-69 years with medical conditions predisposing to severe Covid-19 (chronically ill). Using Cox regression, VE against SARS-CoV-2 infection and Covid-19 hospitalisation was estimated comparing the hazard in the vaccinated with that in the unvaccinated.
The cohorts included 901092 elderly (89% vaccinated) and 774526 chronically ill (69% vaccinated) individuals. Three weeks after the first dose, mRNA VE against infection was 45% (95% confidence interval, 36-53%) and 40% (26-51%) in elderly and chronically ill; mRNA VE against hospitalisation was 63% (49-74%) and 82% (56-93%). In chronically ill, AdV VE was 42% (32-50) and 62% (42-75%) against infection and hospitalisation, respectively. One week after the second dose, mRNA VE against infection was 75% (65-82%) and 77% (65-85%) in elderly and chronically ill; mRNA VE against hospitalisation was 93% (70-98%) and 90% (29-99%).
Covid-19 vaccines protect against SARS-CoV-2 infection and Covid-19 hospitalisation. A single dose provides moderate protection in elderly and chronically ill, although two doses are clearly superior.
在芬兰，自 2020 年 12 月 27 日开始疫苗接种活动以来，已使用信使 RNA（mRNA）和腺病毒载体（AdV）两种新冠疫苗。优先为老年人和慢性病患者接种疫苗，并将两剂疫苗的间隔设定为 12 周。本中期分析的目的是在真实环境中评估第一剂和第二剂疫苗的有效性（VE）。
在疫苗接种活动的头五个月期间，对芬兰 70 岁以上的老年人和患有易患严重新冠疾病的 16-69 岁的慢性病患者进行了基于登记的队列研究。使用 Cox 回归，通过比较疫苗接种者和未接种者的风险，估计针对 SARS-CoV-2 感染和新冠住院的 VE。
队列包括 901092 名老年人（89%接种疫苗）和 774526 名慢性病患者（69%接种疫苗）。接种第一剂疫苗后 3 周，mRNA 对感染的 VE 为 45%（95%置信区间，36-53%）和 40%（26-51%），老年人和慢性病患者；mRNA 对住院的 VE 为 63%（49-74%）和 82%（56-93%）。在慢性病患者中，AdV 对感染和住院的 VE 分别为 42%（32-50%）和 62%（42-75%）。接种第二剂疫苗后 1 周，mRNA 对感染的 VE 为 75%（65-82%）和 77%（65-85%），老年人和慢性病患者；mRNA 对住院的 VE 为 93%（70-98%）和 90%（29-99%）。
新冠疫苗可预防 SARS-CoV-2 感染和新冠住院。一剂疫苗可在老年人和慢性病患者中提供适度的保护，但两剂疫苗显然更优。
