Deng Yangyang, Kim Yun, Bratcher Anna, Jones Jefferson M, Simuzingili Muloongo, Gundlapalli Adi V, Hagen Melissa Briggs, Iachan Ronaldo, Clarke Kristie E N
ICF Macro, inc., Reston, Virginia, USA.
Epidemic Intelligence Service, CDC, Atlanta, Georgia, USA.
Open Forum Infect Dis. 2025 Jan 16;12(1):ofae719. doi: 10.1093/ofid/ofae719. eCollection 2025 Jan.
Understanding the risk of hospitalization from severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infections can guide effective public health interventions and severity assessments. This study calculated infection-hospitalization ratios (IHRs) and infection-case ratios (ICRs) to understand the relationship between SARS-CoV-2 infections, cases, and hospitalizations among different age groups during periods of Delta and Omicron variant predominance.
After calculating antinucleocapsid SARS-CoV-2 antibody seroprevalence using residual commercial laboratory serum specimens, 2 ratios were computed: (1) IHRs using coronavirus disease 2019 hospitalization data and (2) ICRs using Centers for Disease Control and Prevention surveillance data. Ratios were calculated across age groups (0-17, 18-49, 50-69, and ≥70 years) for 2 time periods (September-December 2021 [Delta] and December 2021-February 2022 [Omicron]).
Pediatric IHRs increased from 76.7 during Delta to 258.4 during Omicron. Adult IHRs ranged from 3.0 (≥70 years) to 21.6 (18-49 years) during Delta and from 10.0 (≥70 years) to 119.1 (18-49 years) during Omicron. The pediatric ICR was lower during the Delta period (2.7) compared with the Omicron period (3.7). Adult ICRs (Delta: 1.1 [18-49 years] to 2.1 [70+ years]; Omicron: 2.2 [>70+ years] to 2.9 [50-69 years]) were lower than pediatric ICRs during both time periods.
All age groups exhibited a lower proportion of infections associated with hospitalization in the Omicron period than the Delta period; the proportion of infections associated with hospitalization increased with each older age group. A lower proportion of SARS-CoV-2 infections were associated with reported cases in the Omicron period than in the Delta period among all age groups.
了解严重急性呼吸综合征冠状病毒2（SARS-CoV-2）感染导致住院的风险，可为有效的公共卫生干预措施和病情严重程度评估提供指导。本研究计算了感染住院率（IHR）和感染病例率（ICR），以了解在德尔塔和奥密克戎变异株占主导的时期，不同年龄组中SARS-CoV-2感染、病例和住院之间的关系。
在使用商业实验室剩余血清标本计算抗SARS-CoV-2核衣壳抗体血清流行率后，计算了两个比率：（1）使用2019冠状病毒病住院数据计算的IHR，以及（2）使用疾病控制与预防中心监测数据计算的ICR。在两个时间段（2021年9月至12月[德尔塔]和2021年12月至2022年2月[奥密克戎]），按年龄组（0至17岁、18至49岁、50至69岁和≥70岁）计算比率。
儿童IHR从德尔塔时期的76.7增至奥密克戎时期的258.4。成人IHR在德尔塔时期为3.0（≥70岁）至21.6（18至49岁），在奥密克戎时期为10.0（≥70岁）至119.1（18至49岁）。与奥密克戎时期（3.7）相比，德尔塔时期儿童ICR较低（2.7）。在两个时间段，成人ICR（德尔塔：1.1[18至49岁]至2.1[70岁以上]；奥密克戎：2.2[70岁以上]至2.9[50至69岁]）均低于儿童ICR。
在奥密克戎时期，所有年龄组与住院相关的感染比例均低于德尔塔时期；与住院相关的感染比例随年龄增长而增加。在奥密克戎时期，所有年龄组中与报告病例相关的SARS-CoV-2感染比例均低于德尔塔时期。
