Bureau of Communicable Disease, New York City Department of Health and Mental Hygiene, Long Island City, New York, USA.
Bureau of Epidemiology Services, New York City Department of Health and Mental Hygiene, Long Island City, New York, USA.
Clin Infect Dis. 2023 Feb 8;76(3):e469-e476. doi: 10.1093/cid/ciac380.
Belief that vaccination is not needed for individuals with prior infection contributes to coronavirus disease 2019 (COVID-19) vaccine hesitancy. Among individuals infected with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) before vaccines became available, we determined whether vaccinated individuals had reduced odds of reinfection.
We conducted a case-control study among adult New York City residents who tested positive for SARS-CoV-2 infection in 2020 and had not died or tested positive again >90 days after an initial positive test as of 1 July 2021. Case patients with reinfection during July 2021-November 2021 and controls with no reinfection were matched (1:3) on age, sex, timing of initial positive test in 2020, and neighborhood poverty level. Matched odds ratios (mORs) and 95% confidence intervals (CIs) were calculated using conditional logistic regression.
Of 349 827 eligible adults, 2583 were reinfected during July 2021-November 2021. Of 2401 with complete matching criteria data, 1102 (45.9%) were known to be symptomatic for COVID-19-like illness, and 96 (4.0%) were hospitalized. Unvaccinated individuals, compared with individuals fully vaccinated within the prior 90 days, had elevated odds of reinfection (mOR, 3.21; 95% CI, 2.70 to 3.82), of symptomatic reinfection (mOR, 2.97; 95% CI, 2.31 to 3.83), and of reinfection with hospitalization (mOR, 2.09; 95% CI, .91 to 4.79).
Vaccination reduced odds of reinfections when the Delta variant predominated. Further studies should assess risk of severe outcomes among reinfected persons as new variants emerge, infection- and vaccine-induced immunity wanes, and booster doses are administered.
认为既往感染者无需接种疫苗，这导致了对 2019 年冠状病毒病（COVID-19）疫苗的犹豫。在疫苗问世之前感染严重急性呼吸综合征冠状病毒 2（SARS-CoV-2）的人群中，我们确定了已接种疫苗的个体感染再感染的几率是否降低。
我们对 2020 年在纽约市成年居民中进行了一项病例对照研究，这些居民的 SARS-CoV-2 感染检测呈阳性，且截至 2021 年 7 月 1 日，初始阳性检测后 90 天以上未死亡或再次检测呈阳性。2021 年 7 月至 11 月期间发生再感染的病例患者和未再感染的对照患者按年龄、性别、2020 年首次阳性检测时间和社区贫困水平进行 1:3 匹配。使用条件逻辑回归计算匹配优势比（mOR）和 95%置信区间（CI）。
在 349827 名符合条件的成年人中，有 2583 人在 2021 年 7 月至 11 月期间发生再感染。在 2401 名具有完整匹配标准数据的患者中，有 1102 名（45.9%）已知患有 COVID-19 样疾病症状，有 96 名（4.0%）住院。与在过去 90 天内完全接种疫苗的个体相比，未接种疫苗的个体再感染的几率更高（mOR，3.21；95%CI，2.70 至 3.82）、有症状再感染的几率更高（mOR，2.97；95%CI，2.31 至 3.83），以及再感染导致住院的几率更高（mOR，2.09；95%CI，0.91 至 4.79）。
当 Delta 变异株占主导地位时，疫苗接种降低了再感染的几率。随着新变异株的出现、感染和疫苗诱导的免疫减弱以及加强剂量的接种，应进一步评估再感染人群发生严重结局的风险。
