COVID-19 Response Team, Centers for Disease Control and Prevention, Atlanta, Georgia.
Vitalant Research Institute, San Francisco, California.
JAMA. 2021 Oct 12;326(14):1400-1409. doi: 10.1001/jama.2021.15161.
People who have been infected with or vaccinated against SARS-CoV-2 have reduced risk of subsequent infection, but the proportion of people in the US with SARS-CoV-2 antibodies from infection or vaccination is uncertain.
To estimate trends in SARS-CoV-2 seroprevalence related to infection and vaccination in the US population.
DESIGN, SETTING, AND PARTICIPANTS: In a repeated cross-sectional study conducted each month during July 2020 through May 2021, 17 blood collection organizations with blood donations from all 50 US states; Washington, DC; and Puerto Rico were organized into 66 study-specific regions, representing a catchment of 74% of the US population. For each study region, specimens from a median of approximately 2000 blood donors were selected and tested each month; a total of 1 594 363 specimens were initially selected and tested. The final date of blood donation collection was May 31, 2021.
Calendar time.
Proportion of persons with detectable SARS-CoV-2 spike and nucleocapsid antibodies. Seroprevalence was weighted for demographic differences between the blood donor sample and general population. Infection-induced seroprevalence was defined as the prevalence of the population with both spike and nucleocapsid antibodies. Combined infection- and vaccination-induced seroprevalence was defined as the prevalence of the population with spike antibodies. The seroprevalence estimates were compared with cumulative COVID-19 case report incidence rates.
Among 1 443 519 specimens included, 733 052 (50.8%) were from women, 174 842 (12.1%) were from persons aged 16 to 29 years, 292 258 (20.2%) were from persons aged 65 years and older, 36 654 (2.5%) were from non-Hispanic Black persons, and 88 773 (6.1%) were from Hispanic persons. The overall infection-induced SARS-CoV-2 seroprevalence estimate increased from 3.5% (95% CI, 3.2%-3.8%) in July 2020 to 20.2% (95% CI, 19.9%-20.6%) in May 2021; the combined infection- and vaccination-induced seroprevalence estimate in May 2021 was 83.3% (95% CI, 82.9%-83.7%). By May 2021, 2.1 SARS-CoV-2 infections (95% CI, 2.0-2.1) per reported COVID-19 case were estimated to have occurred.
Based on a sample of blood donations in the US from July 2020 through May 2021, vaccine- and infection-induced SARS-CoV-2 seroprevalence increased over time and varied by age, race and ethnicity, and geographic region. Despite weighting to adjust for demographic differences, these findings from a national sample of blood donors may not be representative of the entire US population.
感染 SARS-CoV-2 或接种 SARS-CoV-2 疫苗的人，其随后感染的风险降低，但美国 SARS-CoV-2 抗体人群的比例尚不确定。
估计美国人群中与感染和疫苗接种相关的 SARS-CoV-2 血清流行率趋势。
设计、地点和参与者：在一项于 2020 年 7 月至 2021 年 5 月期间每月进行的重复横断面研究中，17 个血液采集组织从美国所有 50 个州、华盛顿特区和波多黎各采集血液，这些组织被组织成 66 个特定地区，代表美国 74%的人口的集水区。对于每个研究区域，每月选择并测试中位数约为 2000 名献血者的标本；共选择并测试了 1594363 个标本。最后一次采血日期为 2021 年 5 月 31 日。
日历时间。
具有可检测 SARS-CoV-2 刺突和核衣壳抗体的人的比例。血清流行率根据献血者样本与一般人群之间的人口统计学差异进行加权。感染诱导的血清流行率定义为具有刺突和核衣壳抗体的人群的流行率。合并感染和疫苗接种诱导的血清流行率定义为具有刺突抗体的人群的流行率。将血清流行率估计值与累积 COVID-19 病例报告发病率进行比较。
在纳入的 1443519 份标本中，733052 份（50.8%）来自女性，174842 份（12.1%）来自 16 至 29 岁的人群，292258 份（20.2%）来自 65 岁及以上的人群，36654 份（2.5%）来自非西班牙裔黑人，88773 份（6.1%）来自西班牙裔人。总体感染诱导的 SARS-CoV-2 血清流行率估计值从 2020 年 7 月的 3.5%（95%CI，3.2%-3.8%）增加到 2021 年 5 月的 20.2%（95%CI，19.9%-20.6%）；2021 年 5 月合并感染和疫苗接种诱导的血清流行率估计值为 83.3%（95%CI，82.9%-83.7%）。到 2021 年 5 月，估计每报告 1 例 COVID-19 病例就有 2.1 例 SARS-CoV-2 感染（95%CI，2.0-2.1）。
基于 2020 年 7 月至 2021 年 5 月期间美国血液捐赠的样本，疫苗和感染诱导的 SARS-CoV-2 血清流行率随时间增加，且按年龄、种族和民族以及地理位置不同而有所差异。尽管进行了加权以调整人口统计学差异，但这些来自全国血液捐赠者样本的发现可能无法代表美国的整个人口。
