VA Pittsburgh Healthcare System, Pittsburgh, PA, USA.
CRISMA Center, Department of Critical Care Medicine, University of Pittsburgh, Pittsburgh, PA, USA.
Nat Commun. 2022 Jun 25;13(1):3647. doi: 10.1038/s41467-022-31402-4.
The SARS-CoV-2 Omicron variant is thought to cause less severe disease among the general population, but disease severity among at-risk populations is unknown. We performed a retrospective analysis using a matched cohort of United States veterans to compare the disease severity of subjects infected during Omicron and Delta predominant periods within 14 days of initial diagnosis. We identified 22,841 matched pairs for both periods. During the Omicron period, 20,681 (90.5%) veterans had mild, 1308 (5.7%) moderate, and 852 (3.7%) severe disease. During the Delta predominant period, 19,356 (84.7%) had mild, 1467 (6.4%) moderate, and 2018 (8.8%) severe disease. Moderate or severe disease was less likely during the Omicron period and more common among older subjects and those with more comorbidities. Here we show that infection with the Omicron variant is associated with less severe disease than the Delta variant in a high-risk older veteran population, and vaccinations provide protection against severe or critical disease.
奥密克戎变异株被认为在普通人群中引起的疾病较轻，但在高危人群中的疾病严重程度尚不清楚。我们使用美国退伍军人的匹配队列进行了回顾性分析，比较了在初始诊断后 14 天内奥密克戎和德尔塔变异株流行期间感染患者的疾病严重程度。我们确定了两个时期的 22841 对匹配。在奥密克戎时期，20681 名（90.5%）退伍军人患有轻度疾病，1308 名（5.7%）患有中度疾病，852 名（3.7%）患有重度疾病。在德尔塔为主的时期，19356 名（84.7%）患有轻度疾病，1467 名（6.4%）患有中度疾病，2018 名（8.8%）患有重度疾病。奥密克戎时期的中度或重度疾病较少，而在年龄较大的患者和合并症较多的患者中更为常见。在这里，我们表明在高危老年退伍军人中，与德尔塔变异株相比，感染奥密克戎变异株与疾病较轻相关，而疫苗接种可预防重症或危重症疾病。
