评估延长接种间隔对青少年 mRNA COVID-19 疫苗有效性的影响。

Evaluating the impact of extended dosing intervals on mRNA COVID-19 vaccine effectiveness in adolescents.

机构信息

WHO Collaborating Centre for Infectious Disease Epidemiology and Control, School of Public Health, Li Ka Shing, Faculty of Medicine, The University of Hong Kong, 7 Sassoon Road, Pokfulam, Hong Kong Special Administrative Region, China.

Laboratory of Data Discovery for Health Limited, Hong Kong Science and Technology Park, New Territories, Hong Kong Special Administrative Region, China.

出版信息

BMC Med. 2024 Sep 12;22(1):384. doi: 10.1186/s12916-024-03597-4.

BACKGROUND

Extending the dosing interval of a primary series of mRNA COVID-19 vaccination has been employed to reduce myocarditis risk in adolescents, but previous evaluation of impact on vaccine effectiveness (VE) is limited to risk after second dose.

METHODS

We quantified the impact of the dosing interval based on case notifications and vaccination uptake in Hong Kong from January to April 2022, based on calendar-time proportional hazards models and matching approaches.

RESULTS

We estimated that the hazard ratio (HR) and odds ratio (OR) of infections after the second dose for extended (28 days or more) versus regular (21-27 days) dosing intervals ranged from 0.86 to 0.99 from calendar-time proportional hazards models, and from 0.85 to 0.87 from matching approaches, respectively. Adolescents in the extended dosing groups (including those who did not receive a second dose in the study period) had a higher hazard of infection than those with a regular dosing interval during the intra-dose period (HR 1.66; 95% CI 1.07, 2.59; p = 0.02) after the first dose.

CONCLUSIONS

Implementing an extended dosing interval should consider multiple factors including the degree of myocarditis risk, the degree of protection afforded by each dose, and the extra protection achievable using an extended dosing interval.

背景

为降低青少年心肌炎的风险，已采用延长 mRNA COVID-19 疫苗基础系列接种剂次间隔的方法，但此前对于其对疫苗有效性（VE）影响的评估仅限于第二剂次之后。

方法

我们根据香港 2022 年 1 月至 4 月期间的病例报告和疫苗接种数据，采用日历时间比例风险模型和匹配方法，量化了剂次间隔的影响。

结果

我们估计，对于延长（28 天或以上）与常规（21-27 天）间隔的第二剂次接种，日历时间比例风险模型得出的感染后危险比（HR）和比值比（OR）范围分别为 0.86 至 0.99，匹配方法得出的分别为 0.85 至 0.87。在第一剂次后，与常规剂次间隔相比，延长剂次间隔组（包括研究期间未接种第二剂次的青少年）的感染风险更高（HR 1.66；95%CI 1.07，2.59；p=0.02）。