Although there was some variation across periods, most patients had COVID-19–related symptoms recorded at admission (87%) and COVID-19 as the primary reason for admission (85%). Hospitalization rates among infants and children aged 0–4 years decreased by the week ending Febru(3.9).Ĭomplete clinical data were available for 97% (2,562 of 2,637) of hospitalized infants and children aged 0–4 years, including 99% (1,200 of 1,209), 94% (790 of 841), and 97% (572 of 587) hospitalized during the pre-Delta–, Delta- and Omicron-predominant periods, respectively ( Table 1). Monthly ICU admission rates were approximately 3.5 times as high during the Omicron predominance peak in January 2022 (10.6) as during the Delta predominance peak in September 2021 (3.0). Hospitalization rates among infants aged <6 months were approximately six times as high during the peak week of Omicron predominance (68.1) as during Delta predominance (11.1) (RR = 6.1 95% CI = 3.9–10.0) Omicron-predominant versus Delta-predominant hospitalization RRs were also elevated among infants and children aged 6–23 months (16.9 versus 3.3 RR = 5.1 95% CI = 3.1–8.5) and 2–4 years (4.7 versus 1.4 RR = 3.5 95% CI = 2.0–6.3) ( Figure). This peak hospitalization rate during Omicron predominance was approximately five times the peak during Delta predominance (2.9) (week ending September 11, 2021) (RR = 5.0 95% CI = 3.8–6.8). §§§ĭuring March 1, 2020–February 19, 2022, weekly hospitalization rates (hospitalized patients per 100,000 infants and children aged 0–4 years) peaked during Omicron predominance, in the week ending January 8, 2022, at 14.5. This activity was reviewed by CDC and was conducted consistent with applicable federal law and CDC policy. Data were analyzed using SAS (version 9.4 SAS Institute).

Percentages were weighted to account for the probability of selection for sampled cases and adjusted to account for nonresponse. Wilcoxon rank-sum tests and chi-square tests were used to compare medians and proportions, respectively p-values <0.05 were considered statistically significant. For the period of Omicron predominance, proportions were compared by age (<6 months, 6–23 months, and 2–4 years). § During Omicron predominance, 63% of hospitalized infants and children had no underlying medical conditions infants aged 50% of sequenced isolates was considered predominant. During the period of Omicron predominance (December 19, 2021–February 19, 2022), weekly COVID-19–associated hospitalization rates per 100,000 infants and children aged 0–4 years peaked at 14.5 (week ending January 8, 2022) this Omicron-predominant period peak was approximately five times that during the period of SARS-CoV-2 B.1.617.2 (Delta) predominance (June 27–December 18, 2021, which peaked the week ending September 11, 2021). infants and children aged 0–4 years since March 2020.

Coronavirus Disease 19–Associated Hospitalization Surveillance Network (COVID-NET) † data were analyzed to describe COVID-19–associated hospitalizations among U.S. The B.1.1.529 (Omicron) variant of SARS-CoV-2, the virus that causes COVID-19, has been the predominant circulating variant in the United States since late December 2021.* Coinciding with increased Omicron circulation, COVID-19–associated hospitalization rates increased rapidly among infants and children aged 0–4 years, a group not yet eligible for vaccination ( 1).

Erica cobb