MMWR Morb Mortal Wkly Rep. 2022 Nov 11;71(45):1442-1448. doi: 10.15585/mmwr.mm7145a3.
COVID-19-associated hospitalization rates are highest among adults aged ≥65 years (1); however, COVID-19 can and does cause severe and fatal outcomes in children, including infants (2,3). After the emergence of the SARS-CoV-2 B.1.1.529 (Omicron) BA.1 variant in December 2021, hospitalizations among children aged <5 years, who were ineligible for vaccination, increased more rapidly than did those in other age groups (4). On June 18, 2022, CDC recommended COVID-19 vaccination for infants and children aged ≥6 months (5). Data from the Coronavirus Disease 2019-Associated Hospitalization Surveillance Network (COVID-NET)* were analyzed to describe changes in the age distribution of COVID-19-associated hospitalizations since the Delta-predominant period (June 20-December 18, 2021) with a focus on U.S. infants aged <6 months. During the Omicron BA.2/BA.5-predominant periods (December 19, 2021–August 31, 2022), weekly hospitalizations per 100,000 infants aged <6 months increased from a nadir of 2.2 (week ending April 9, 2022) to a peak of 26.0 (week ending July 23, 2022), and the average weekly hospitalization rate among these infants (13.7) was similar to that among adults aged 65-74 years (13.8). However, the prevalence of indicators of severe disease among hospitalized infants did not increase since the B.1.617.2 (Delta)-predominant period. To help protect infants too young to be vaccinated, prevention should focus on nonpharmaceutical interventions and vaccination of pregnant women, which might provide protection through transplacental transfer of antibodies (6).
COVID-19 相关住院率在≥65 岁的成年人中最高(1);然而,COVID-19 可导致儿童(包括婴儿)出现严重和致命后果(2,3)。2021 年 12 月 SARS-CoV-2 B.1.1.529(Omicron)BA.1 变异株出现后,未接种疫苗的<5 岁儿童住院率增长速度快于其他年龄组(4)。2022 年 6 月 18 日,CDC 建议≥6 个月的婴儿和儿童接种 COVID-19 疫苗(5)。对冠状病毒疾病 2019 相关住院监测网络(COVID-NET)*的数据进行分析,以描述 Delta 主导时期(2021 年 6 月 20 日至 12 月 18 日)以来 COVID-19 相关住院人数的年龄分布变化,重点是美国<6 个月的婴儿。在 Omicron BA.2/BA.5 主导时期(2021 年 12 月 19 日至 2022 年 8 月 31 日),每 10 万<6 个月婴儿每周住院人数从 4 月 9 日(第 15 周)的最低点 2.2 增加到 7 月 23 日(第 30 周)的峰值 26.0,这些婴儿的平均每周住院率(13.7)与 65-74 岁成年人相似(13.8)。然而,自 B.1.617.2(Delta)主导时期以来,住院婴儿严重疾病指标的流行率并未增加。为了帮助保护太小而不能接种疫苗的婴儿,预防措施应侧重于非药物干预和孕妇接种疫苗,这可能通过抗体的胎盘转移提供保护(6)。