MMWR Morb Mortal Wkly Rep. 2022 Mar 25;71(12):466-473. doi: 10.15585/mmwr.mm7112e2.
Beginning the week of December 19-25, 2021, the B.1.1.529 (Omicron) variant of SARS-CoV-2 (the virus that causes COVID-19) became the predominant circulating variant in the United States (i.e., accounted for >50% of sequenced isolates).* Information on the impact that booster or additional doses of COVID-19 vaccines have on preventing hospitalizations during Omicron predominance is limited. Data from the COVID-19-Associated Hospitalization Surveillance Network (COVID-NET) were analyzed to compare COVID-19-associated hospitalization rates among adults aged ≥18 years during B.1.617.2 (Delta; July 1-December 18, 2021) and Omicron (December 19, 2021-January 31, 2022) variant predominance, overall and by race/ethnicity and vaccination status. During the Omicron-predominant period, weekly COVID-19-associated hospitalization rates (hospitalizations per 100,000 adults) peaked at 38.4, compared with 15.5 during Delta predominance. Hospitalizations rates increased among all adults irrespective of vaccination status (unvaccinated, primary series only, or primary series plus a booster or additional dose). Hospitalization rates during peak Omicron circulation (January 2022) among unvaccinated adults remained 12 times the rates among vaccinated adults who received booster or additional doses and four times the rates among adults who received a primary series, but no booster or additional dose. The rate among adults who received a primary series, but no booster or additional dose, was three times the rate among adults who received a booster or additional dose. During the Omicron-predominant period, peak hospitalization rates among non-Hispanic Black (Black) adults were nearly four times the rate of non-Hispanic White (White) adults and was the highest rate observed among any racial and ethnic group during the pandemic. Compared with the Delta-predominant period, the proportion of unvaccinated hospitalized Black adults increased during the Omicron-predominant period. All adults should stay up to date (1) with COVID-19 vaccination to reduce their risk for COVID-19-associated hospitalization. Implementing strategies that result in the equitable receipt of COVID-19 vaccinations, through building vaccine confidence, raising awareness of the benefits of vaccination, and removing barriers to vaccination access among persons with disproportionately higher hospitalizations rates from COVID-19, including Black adults, is an urgent public health priority.
从 2021 年 12 月 19 日至 25 日那一周开始，SARS-CoV-2（引发 COVID-19 的病毒）的 B.1.1.529（奥密克戎）变体成为美国主要传播的变体（即，占测序分离株的 50%以上）。*关于 COVID-19 疫苗加强针或额外剂量对奥密克戎流行期间预防住院的影响的信息有限。对 COVID-19 相关住院监测网络（COVID-NET）的数据进行了分析，以比较 18 岁及以上成年人在 B.1.617.2（德尔塔；2021 年 7 月 1 日至 12 月 18 日）和奥密克戎（2021 年 12 月 19 日至 2022 年 1 月 31 日）变体为主导期间 COVID-19 相关住院率，总体以及按种族/族裔和疫苗接种状况进行比较。在奥密克戎为主导的时期，每周 COVID-19 相关住院率（每 10 万成年人中的住院人数）峰值为 38.4，而德尔塔为主导时期为 15.5。所有成年人的住院率均有所增加，无论其疫苗接种状况如何（未接种、仅接种初级系列或接种初级系列加加强针或额外剂量）。在奥密克戎传播高峰期（2022 年 1 月），未接种疫苗的成年人的住院率仍然是接种加强针或额外剂量的成年人的 12 倍，是未接种初级系列但接种了加强针或额外剂量的成年人的 4 倍。未接种疫苗的成年人的住院率是仅接种加强针或额外剂量的成年人的 3 倍。在奥密克戎为主导的时期，非西班牙裔黑人（黑人）成年人的住院率峰值几乎是西班牙裔白人（白人）成年人的四倍，是大流行期间任何种族和族裔群体中观察到的最高率。与德尔塔为主导的时期相比，奥密克戎为主导的时期未接种疫苗的住院黑人成年人比例有所增加。所有成年人都应及时接种 COVID-19 疫苗，以降低 COVID-19 相关住院的风险。实施通过建立疫苗信心、提高对疫苗益处的认识以及消除疫苗接种障碍等策略，使 COVID-19 住院率较高的人群（包括黑人成年人）公平地获得 COVID-19 疫苗，这是一项紧迫的公共卫生优先事项。
