Instituto Nacional de Ciencias Médicas y Nutrición Salvador Zubirán, Mexico City, Mexico.
Rev Invest Clin. 2022;74(4):175-180. doi: 10.24875/RIC.22000159.
Relatively low SARS-CoV-2 reinfection rates have been reported in vaccinated individuals, but updates considering the Omicron variant are lacking.
The objective of the study was to provide a current estimate of the SARS-CoV-2 reinfection rate in a highly immunized population.
A prospective cohort of Mexican hospital workers was followed (March 2020-February 2022). Reinfection was defined as the occurrence of two or more episodes of COVID-19 separated by a period of ≥ 90 days without symptoms. The reinfection rate was calculated as the number of reinfection episodes per 100,000 persons per day.
A total of 3732 medical consultations were provided to 2700 workers, of whom 1388 (51.4%) were confirmed COVID-19 cases. A total of 73 reinfection cases were identified, of whom 71 (97.3%) had completed their primary vaccination series and 22 (30.1%) had had a booster dose before the second episode. The overall reinfection rate was 23.1 per 100,000 persons per day (as compared to a rate of 1.9 per 100,000 persons per day before the Omicron wave).
The SARS-CoV-2 reinfection rate rose significantly during the Omicron wave despite a high primary vaccination coverage rate. Almost one-third of reinfected workers had a vaccine booster ≥ 14 days before the last COVID-19 episode.
已报道接种疫苗者的 SARS-CoV-2 再感染率相对较低，但缺乏针对奥密克戎变异株的更新数据。
本研究旨在提供在高免疫人群中 SARS-CoV-2 再感染率的最新估计。
对墨西哥医院工作人员进行前瞻性队列研究（2020 年 3 月至 2022 年 2 月）。再感染定义为两次或两次以上 COVID-19 发作，两次发作间隔≥90 天且无症状。再感染率以每 10 万人每天的再感染例数计算。
共为 2700 名工作人员提供了 3732 次医疗咨询，其中 1388 人（51.4%）被确诊为 COVID-19 病例。共发现 73 例再感染病例，其中 71 例（97.3%）已完成初级疫苗接种系列，22 例（30.1%）在第二次发作前已接种加强针。总体再感染率为 23.1/10 万人/天（奥密克戎波前为 1.9/10 万人/天）。
尽管初级疫苗接种覆盖率很高，但在奥密克戎波期间，SARS-CoV-2 再感染率显著上升。近三分之一的再感染工人在最后一次 COVID-19 发作前≥14 天接种了疫苗加强针。
