CDC COVID-19 Response Team, Atlanta, Georgia, USA.
Vanderbilt University Medical Center, Nashville, Tennessee, USA.
Clin Infect Dis. 2023 Feb 8;76(3):e460-e468. doi: 10.1093/cid/ciac381.
Coronavirus disease 2019 (COVID-19) messenger RNA (mRNA) vaccines were authorized in the United States in December 2020. Although vaccine effectiveness (VE) against mild infection declines markedly after several months, limited understanding exists on the long-term durability of protection against COVID-19-associated hospitalization.
Case-control analysis of adults (≥18 years) hospitalized at 21 hospitals in 18 states 11 March-15 December 2021, including COVID-19 case patients and reverse transcriptase-polymerase chain reaction-negative controls. We included adults who were unvaccinated or vaccinated with 2 doses of a mRNA vaccine before the date of illness onset. VE over time was assessed using logistic regression comparing odds of vaccination in cases versus controls, adjusting for confounders. Models included dichotomous time (<180 vs ≥180 days since dose 2) and continuous time modeled using restricted cubic splines.
A total of 10 078 patients were included, 4906 cases (23% vaccinated) and 5172 controls (62% vaccinated). Median age was 60 years (interquartile range, 46-70), 56% were non-Hispanic White, and 81% had ≥1 medical condition. Among immunocompetent adults, VE <180 days was 90% (95% confidence interval [CI], 88-91) versus 82% (95% CI, 79-85) at ≥180 days (P < .001). VE declined for Pfizer-BioNTech (88% to 79%, P < .001) and Moderna (93% to 87%, P < .001) products, for younger adults (18-64 years) (91% to 87%, P = .005), and for adults ≥65 years of age (87% to 78%, P < .001). In models using restricted cubic splines, similar changes were observed.
In a period largely predating Omicron variant circulation, effectiveness of 2 mRNA doses against COVID-19-associated hospitalization was largely sustained through 9 months.
2020 年 12 月，美国批准了针对 2019 年冠状病毒病（COVID-19）信使 RNA（mRNA）疫苗。尽管疫苗有效性（VE）对轻度感染的保护作用在几个月后明显下降，但对 COVID-19 相关住院治疗的长期保护持久性的了解有限。
这是一项在 2021 年 3 月 11 日至 12 月 15 日期间，在 18 个州的 21 家医院进行的成年（≥18 岁）住院患者的病例对照分析，包括 COVID-19 病例患者和逆转录酶-聚合酶链反应阴性对照者。我们纳入了在发病前未接种疫苗或接种了 2 剂 mRNA 疫苗的成年人。使用病例与对照者之间的接种几率比较，通过逻辑回归评估时间变化的 VE，并针对混杂因素进行调整。模型包括二分类时间（<180 天与≥180 天）和使用受限立方样条的连续时间模型。
共纳入 10078 例患者，4906 例病例（23%接种疫苗）和 5172 例对照（62%接种疫苗）。中位年龄为 60 岁（四分位间距，46-70），56%为非西班牙裔白人，81%有≥1 种合并症。在免疫功能正常的成年人中，<180 天的 VE 为 90%（95%置信区间，88%-91%），而≥180 天的 VE 为 82%（95%置信区间，79%-85%）（P<0.001）。辉瑞-生物技术公司（Pfizer-BioNTech）和莫德纳（Moderna）产品的 VE 下降（88%降至 79%，P<0.001），年轻成年人（18-64 岁）的 VE 下降（91%降至 87%，P=0.005），65 岁及以上成年人的 VE 下降（87%降至 78%，P<0.001）。在使用受限立方样条的模型中，也观察到了类似的变化。
在很大程度上早于奥密克戎变体传播的时期，2 剂 mRNA 疫苗对 COVID-19 相关住院的有效性在 9 个月内基本保持不变。
