Hara Megumi, Furue Takeki, Fukuoka Mami, Iwanaga Kentaro, Matsuishi Eijo, Miike Toru, Sakamoto Yuichiro, Mukai Naoko, Kinugasa Yuki, Shigyo Mutsumi, Sonoda Noriko, Tanaka Masato, Arase Yasuko, Tanaka Yosuke, Nakashima Hitoshi, Irie Shin, Hirota Yoshio
Department of Preventive Medicine, Faculty of Medicine, Saga University, 5-1-1 Nabeshima, Saga 849-8501, Japan.
Fukuoka City Office, 1-8-1 Tenjin, Chuohku, Fukuoka 810-8620, Japan.
Vaccines (Basel). 2022 May 14;10(5):779. doi: 10.3390/vaccines10050779.
The real-world effectiveness of the coronavirus disease 2019 (COVID-19) vaccines in Japan remains unclear. This case-control study evaluated the vaccine effectiveness (VE) of two doses of mRNA vaccine, BNT162b2 or mRNA-1273, against the delta (B.1.617.2) variant in the Japanese general population in the period June-September 2021. Individuals in close contact with COVID-19 patients were tested using polymerase chain reaction (PCR). A self-administered questionnaire evaluated vaccination status, demographic data, underlying medical conditions, lifestyle, personal protective health behaviors, and living environment. Two vaccine doses were reported by 11.6% of cases ( = 389) and 35.2% of controls ( = 179). Compared with controls, cases were younger and had a lower proportion who always performed handwashing for ≥20 s, a higher proportion of alcohol consumers, and a lower proportion of individuals living in single-family homes or with commuting family members. After adjusting for these confounding factors and day of PCR testing by multivariate logistic regression analysis, the VE in the period June-July (delta variant proportion 45%) was 92% and 79% in the period August-September (delta variant proportion 89%). The adjusted VE for homestay, hotel-based isolation and quarantine, and hospitalization was 78%, 77%, and 97%, respectively. Despite declining slightly, VE against hospitalization remained robust for ~3 months after the second dose. Vaccination policymaking will require longer-term monitoring of VE against new variants.
2019冠状病毒病（COVID-19）疫苗在日本的实际效果仍不明确。这项病例对照研究评估了两剂mRNA疫苗BNT162b2或mRNA-1273针对2021年6月至9月期间日本普通人群中德尔塔（B.1.617.2）变异株的疫苗效力（VE）。对与COVID-19患者密切接触的个体进行聚合酶链反应（PCR）检测。通过一份自行填写的问卷评估疫苗接种状况、人口统计学数据、基础疾病、生活方式、个人防护健康行为和生活环境。11.6%的病例（n = 389）和35.2%的对照者（n = 179）报告接种了两剂疫苗。与对照者相比，病例更年轻，经常洗手≥20秒的比例更低，饮酒者比例更高，居住在独栋房屋或与通勤家庭成员同住的个体比例更低。通过多因素逻辑回归分析对这些混杂因素和PCR检测日期进行调整后，6月至7月期间（德尔塔变异株比例为45%）的疫苗效力为92%，8月至9月期间（德尔塔变异株比例为89%）为79%。针对居家、酒店隔离检疫和住院治疗的调整后疫苗效力分别为78%、77%和97%。尽管略有下降，但第二剂疫苗接种后约3个月内针对住院治疗的疫苗效力仍然强劲。疫苗接种政策制定将需要对针对新变异株的疫苗效力进行长期监测。
