Abstract
By employing a common protocol and data from electronic health registries in Denmark, Navarre (Spain), Norway and Portugal, we estimated vaccine effectiveness (VE) against hospitalisation due to COVID-19 in individuals aged ≥ 65 years old, without previous documented infection, between October 2021 and March 2022. VE was higher in 65-79-year-olds compared with ≥ 80-year-olds and in those who received a booster compared with those who were primary vaccinated. VE remained high (ca 80%) between ≥ 12 and < 24 weeks after the first booster administration, and after Omicron became dominant.
Keywords: COVID-19; delta variant; omicron variant; vaccination booster dose; vaccination primary course; vaccine effectiveness.
【저자키워드】 COVID-19, delta variant, Omicron variant, vaccine effectiveness., vaccination booster dose, vaccination primary course, 【초록키워드】 Vaccine, vaccination, protocol, Infection, omicron, delta variant, Health, Effectiveness, Spain, Omicron variant, Denmark, Portugal, Norway, hospitalisation, booster, administration, individual, dominant, remained, 【제목키워드】 COVID-19 vaccine, Health, Effectiveness, estimation, pilot study, individual,