IMPORTANCE: Routine vaccinations are key to prevent outbreaks of vaccine-preventable diseases. However, there have been documented declines in routine childhood vaccinations in the U.S. and worldwide during the COVID-19 pandemic. OBJECTIVE: Assess how the COVID-19 pandemic impacted routine childhood vaccinations by evaluating vaccination coverage for routine childhood vaccinations for children born in 2016-2021. METHODS: Data on routine childhood vaccinations reported to CDC by nine U.S. jurisdictions via the immunization information systems (IISs) by December 31, 2022, were available for analyses. Population size for each age group was obtained from the National Center for Health Statistics' Bridging Population Estimates. MAIN OUTCOMES AND MEASURES: Vaccination coverage for routine childhood vaccinations at age three months, five months, seven months, one year, and two years was calculated by vaccine type and overall, for 4:3:1:3:3:1:4 series (≥4 doses DTaP, ≥3 doses Polio, ≥1 dose MMR, ≥3 doses Hib, ≥3 doses Hepatitis B, ≥1 dose Varicella, and ≥ 4 doses pneumococcal conjugate), for each birth cohort year and by jurisdiction. RESULTS: Overall, there was a 10.4 percentage point decrease in the 4:3:1:3:3:1:4 series in those children born in 2020 compared to those children born in 2016. As of December 31, 2022, 71.0% and 71.3% of children born in 2016 and 2017, respectively, were up to date on their routine childhood vaccinations by two years of age compared to 69.1%, 64.7% and 60.6% for children born in 2018, 2019, and 2020, respectively. CONCLUSIONS AND RELEVANCE: The decline in vaccination coverage for routine childhood vaccines is concerning. In order to protect population health, strategic efforts are needed by health care providers, schools, parents, as well as state, local, and federal governments to work together to address these declines in vaccination coverage during the COVID-19 pandemic to prevent outbreaks of vaccine preventable diseases by maintaining high levels of population immunity.

BACKGROUND: Although psychiatric disorders have been associated with reduced immune responses to other vaccines, it remains unknown whether they influence COVID-19 vaccine effectiveness (VE). This study evaluated risk of COVID-19 hospitalization and estimated mRNA VE stratified by psychiatric disorder status. METHODS: In a retrospective cohort analysis of the VISION Network in four US states, the rate of laboratory-confirmed COVID-19-associated hospitalization between December 2021 and August 2022 was compared across psychiatric diagnoses and by monovalent mRNA COVID-19 vaccination status using Cox proportional hazards regression. RESULTS: Among 2,436,999 adults, 22.1% had ≥1 psychiatric disorder. The incidence of COVID-19-associated hospitalization was higher among patients with any versus no psychiatric disorder (394 vs. 156 per 100,000 person-years, p < 0.001). Any psychiatric disorder (adjusted hazard ratio [aHR], 1.27; 95% CI, 1.18-1.37) and mood (aHR, 1.25; 95% CI, 1.15-1.36), anxiety (aHR, 1.33, 95% CI, 1.22-1.45), and psychotic (aHR, 1.41; 95% CI, 1.14-1.74) disorders were each significant independent predictors of hospitalization. Among patients with any psychiatric disorder, aHRs for the association between vaccination and hospitalization were 0.35 (95% CI, 0.25-0.49) after a recent second dose, 0.08 (95% CI, 0.06-0.11) after a recent third dose, and 0.33 (95% CI, 0.17-0.66) after a recent fourth dose, compared to unvaccinated patients. Corresponding VE estimates were 65%, 92%, and 67%, respectively, and were similar among patients with no psychiatric disorder (68%, 92%, and 79%). CONCLUSION: Psychiatric disorders were associated with increased risk of COVID-19-associated hospitalization. However, mRNA vaccination provided similar protection regardless of psychiatric disorder status, highlighting its benefit for individuals with psychiatric disorders.

In October 2023, the Advisory Committee on Immunization Practices (ACIP) voted to approve the Recommended Adult Immunization Schedule for Ages 19 Years or Older, United States, 2024. The 2024 adult immunization schedule, available at www.cdc.gov/vaccines/schedules/hcp/imz/adult.html, summarizes ACIP recommendations in the cover page, tables, notes, appendix, and addendum (Figure). The full ACIP recommendations for each vaccine are available at www.cdc.gov/vaccines/hcp/acip-recs/index.html. The 2024 schedule has also been approved by the director of the Centers for Disease Control and Prevention (CDC) and by the American College of Physicians (www.acponline.org), the American Academy of Family Physicians (www.aafp.org), the American College of Obstetricians and Gynecologists (www.acog.org), the American College of Nurse-Midwives (www.midwife.org), the American Academy of Physician Associates (www.aapa.org), the American Pharmacists Association (www.pharmacist.com), and the Society for Healthcare Epidemiology of America (www.shea-online.org).

At its October 2023 meeting, the Advisory Committee on Immunization Practices* (ACIP) approved the Recommended Adult Immunization Schedule for Ages 19 Years or Older, United States, 2024. The adult immunization schedule, which can be found on the CDC immunization schedule website (https://www.cdc.gov/vaccines/schedules), is published annually to consolidate and summarize updates to ACIP recommendations on the vaccination of adults and to assist health care providers in implementing current ACIP recommendations. The 2024 immunization schedule includes several changes to the cover page, tables, notes, and appendix from the 2023 immunization schedule.(†) In addition, the 2024 adult immunization schedule includes a new addendum section that summarizes new or updated ACIP recommendations that will occur before the next annual update to the adult immunization schedule. Health care providers are advised to use the cover page, tables, notes, appendix, and addendum together to determine recommended vaccinations for patient populations.

At its October 2023 meeting, the Advisory Committee on Immunization Practices* (ACIP) approved the Recommended Child and Adolescent Immunization Schedule for Ages 18 Years or Younger, United States, 2024. The child and adolescent immunization schedule, which can be found on the CDC immunization schedule website (https://www.cdc.gov/vaccines/schedules), is published annually to consolidate and summarize updates to ACIP recommendations on the vaccination of children and adolescents and to assist health care providers in implementing current ACIP recommendations. The 2024 immunization schedule includes several changes to the cover page, tables, notes, and appendix from the 2023 immunization schedule.(†) In addition, the 2024 child and adolescent immunization schedule includes a new addendum section to summarize new or updated ACIP recommendations that will occur before the next annual update to the child and adolescent immunization schedule. Health care providers are advised to use the cover page, tables, notes, appendix, and addendum together to identify the recommended immunizations for patient populations.

Repeat vaccination with egg-based influenza vaccines could preferentially boost antibodies targeting the egg-adapted epitopes and reduce immunogenicity to circulating viruses. In this randomized trial (Clinicaltrials.gov: NCT03722589), sera pre- and post-vaccination with quadrivalent inactivated egg-based (IIV4), cell culture-based (ccIIV4), and recombinant (RIV4) influenza vaccines were collected from healthcare personnel (18-64 years) in 2018-19 (N = 723) and 2019-20 (N = 684) influenza seasons. We performed an exploratory analysis. Vaccine egg-adapted changes had the most impact on A(H3N2) immunogenicity. In year 1, RIV4 induced higher neutralizing and total HA head binding antibodies to cell- A(H3N2) virus than ccIIV4 and IIV4. In year 2, among the 7 repeat vaccination arms (IIV4-IIV4, IIV4-ccIIV4, IIV4-RIV4, RIV4-ccIIV4, RIV4-RIV4, ccIIV4-ccIIV4 and ccIIV4-RIV4), repeat vaccination with either RIV4 or ccIIV4 further improved antibody responses to circulating viruses with decreased neutralizing antibody egg/cell ratio. RIV4 also had higher post-vaccination A(H1N1)pdm09 and A(H3N2) HA stalk antibodies in year 1, but there was no significant difference in HA stalk antibody fold rise among vaccine groups in either year 1 or year 2. Multiple seasons of non-egg-based vaccination may be needed to redirect antibody responses from immune memory to egg-adapted epitopes and re-focus the immune responses towards epitopes on the circulating viruses to improve vaccine effectiveness.

Immunizations are an important tool to reduce the burden of vaccine preventable diseases and improve population health.(1) High-quality immunization data is essential to inform clinical and public health interventions and respond to outbreaks of vaccine-preventable diseases. To track COVID-19 vaccines and vaccinations, CDC established an integrated network that included vaccination provider systems, health information exchange systems, immunization information systems, pharmacy and dialysis systems, vaccine ordering systems, electronic health records, and tools to support mass vaccination clinics. All these systems reported data to CDC's COVID-19 response system (either directly or indirectly) where it was processed, analyzed, and disseminated. This unprecedented vaccine tracking effort provided essential information for public health officials that was used to monitor the COVID-19 response and guide decisions. This paper will describe systems, processes, and policies that enabled monitoring and reporting of COVID-19 vaccination efforts and share challenges and lessons learned for future public health emergency responses.

BACKGROUND: The epidemiology of COVID-19 continues to develop with emerging variants, expanding population-level immunity, and advances in clinical care. We describe changes in the clinical epidemiology of hospitalized COVID-19 and risk factors for critical outcomes over time. METHODS: We included adults aged ≥18 years from 10 states hospitalized with COVID-19 June 2021-March 2023 when multiple SARS-CoV-2 variants or sub-lineages predominated. We evaluated changes in baseline demographic and clinical characteristics and critical outcomes (intensive care unit admission and/or death) and used regression models to evaluate critical outcomes risk factors (risk ratios) stratified by COVID-19 vaccination status. RESULTS: 60,488 COVID-19-associated hospitalizations were included in the analysis. Among those hospitalized, from Delta period (June-December 2021) to the Omicron post-BA.4/BA.5 period (September 2022-March 2023), median age increased from 60 to 75 years, proportion vaccinated increased from 18.2% to 70.1%, while critical outcomes declined from 24.8% to 19.4% (all p < 0.001). Compared to all hospitalization events, those with critical outcomes had a higher proportion of four or more categories of medical conditions categories assessed (32.8% critical versus 23.0% all hospitalized). Critical outcome risk factors were similar for unvaccinated and vaccinated populations; presence of ≥4 medical condition categories was most strongly associated with risk of critical outcomes regardless of vaccine status (unvaccinated aRR 2.27 [95% CI: 2.14-2.41]; vaccinated aRR 1.73 [95% CI: 1.56-1.92]) across periods. CONCLUSION: The proportion of adults hospitalized with COVID-19 who experienced critical outcomes decreased with time and median patient age increased with time. Multimorbidity was mostly strongly associated with critical outcomes.

Background As of August 21, 2021, &gt;60% of the U.S. population aged ≥18 years were fully vaccinated with vaccines highly effective in preventing hospitalization due to Coronavirus Disease-2019 (COVID-19). Infection despite full vaccination (vaccine breakthrough) has been reported, but characteristics of those with vaccine breakthrough resulting in hospitalization and relative rates of hospitalization in unvaccinated and vaccinated persons are not well described, including during late June and July 2021 when the highly transmissible Delta variant predominated.Methods From January 1–June 30, 2021, cases defined as adults aged ≥18 years with laboratory-confirmed Severe Acute Respiratory Coronavirus-2 (SARS-CoV-2) infection were identified from &gt;250 acute care hospitals in the population-based COVID-19-Associated Hospitalization Surveillance Network (COVID-NET). Through chart review for sampled cases, we examine characteristics associated with vaccination breakthrough. From January 24–July 24, 2021, state immunization information system data linked to both &gt;37,000 cases representative cases and the defined surveillance catchment area population were used to compare weekly hospitalization rates in vaccinated and unvaccinated individuals. Unweighted case counts and weighted percentages are presented.Results From January 1 – June 30, 2021, fully vaccinated cases increased from 1 (0.01%) to 321 (16.1%) per month. Among 4,732 sampled cases, fully vaccinated persons admitted with COVID-19 were older compared with unvaccinated persons (median age 73 years [Interquartile Range (IQR) 65-80] v. 59 years [IQR 48-70]; p&lt;0.001), more likely to have 3 or more underlying medical conditions (201 (70.8%) v. 2,305 (56.1%), respectively; p&lt;0.001) and be residents of long-term care facilities [37 (14.5%) v. 146 (5.5%), respectively; p&lt;0.001]. From January 24 – July 24, 2021, cumulative hospitalization rates were 17 times higher in unvaccinated persons compared with vaccinated persons (423 cases per 100,000 population v. 26 per 100,000 population, respectively); rate ratios were 23, 22 and 13 for those aged 18-49, 50-64, and ≥65 years respectively. For June 27 – July 24, hospitalization rates were ≥10 times higher in unvaccinated persons compared with vaccinated persons for all age groups across all weeks.Conclusion Population-based hospitalization rates show that unvaccinated adults aged ≥18 years are 17 times more likely to be hospitalized compared with vaccinated adults. Rates are far higher in unvaccinated persons in all adult age groups, including during a period when the Delta variant was the predominant strain of the SARS-CoV-2 virus. Vaccines continue to play a critical role in preventing serious COVID-19 illness and remain highly effective in preventing COVID-19 hospitalizations.Competing Interest StatementAll authors have completed and submitted the International Committee of Medical Journal Editors form for disclosure of potential conflicts of interest. Evan J. Anderson reports grants from Pfizer, grants from Merck, grants from PaxVax, grants from Micron, grants from Sanofi-Pasteur, grants from Janssen, grants from MedImmune, grants from GSK, personal fees from Sanofi-Pasteur, personal fees from Pfizer, personal fees from Medscape, personal fees from Kentucky Bioprocessing, Inc, personal fees from Sanofi-Pasteur, personal fees from Janssen, outside the submitted work; and his institution has also received funding from NIH to conduct clinical trials of Moderna and Janssen COVID-19 vaccines. Ruth Lynfield reports Associate Editor for American Academy of Pediatrics Red Book (Committee on Infectious Diseases), donated fee to Minnesota Department of Health. Laurie M. Billing reports grants from Council of State and Territorial Epidemiologists (CSTE), during the conduct of the study; grants from Centers for Disease Control and Prevention (CDC) outside the submitted work. William Schaffner reports personal fees from VBI Vaccines, outside the submitted work. No other potential conflicts of interest were disclosed.Funding StatementThis work was supported by the Centers of Disease Control and Prevention through an Emerging Infections Program cooperative agreement (grant CK17-1701) and through a Council of State and Territorial Epidemiologists cooperative agreement (grant NU38OT000297-02-00).Author DeclarationsI confirm all relevant ethical guidelines have been followed, and any necessary IRB and/or ethics committee approvals have been obtained.YesThe details of the IRB/oversight body that provided approval or exemption for the research described are given below:This activity was reviewed by CDC and was conducted consistent with applicable federal law and CDC policy (see e.g., 45 C.F.R. part 46.102(l)(2), 21 C.F.R. part 56; 42 U.S.C. 241(d); 5 U.S.C.All necessary patient/participant consent has been obtained and the appropriate institutional forms have been archived.YesI understand that all clinical trials and any other prospective interventional studies must be registered with an ICMJE-approved registry, such as ClinicalTrials.gov. I confirm that any such study reported in the manuscript has been registered and the trial registration ID is provided (note: if posting a prospective study registered retrospectively, please provide a statement in the trial ID field explaining why the study was not registered in advance).YesI have followed all appropriate research reporting guidelines and uploaded the relevant EQUATOR Network research reporting checklist(s) and other pertinent material as supplementary files, if applicable.YesPublicly available data referred to in this analysis can be found at: https://gis.cdc.gov/grasp/covidnet/covid19_3.html https://gis.cdc.gov/grasp/COVIDNet/COVID19_5.html https://gis.cdc.gov/grasp/covidnet/covid19_3.html https://gis.cdc.gov/grasp/COVIDNet/COVID19_5.html

Law Enforcement Officers (LEOs), firefighters, and other first responders are at increased risk of SARS-CoV-2 infection compared to healthcare personnel but have relatively low COVID-19 vaccine uptake. Resistance to COVID-19 vaccine mandates among first responders has the potential to disrupt essential public services and threaten public health and safety. Using data from the HEROES-RECOVER prospective cohorts, we report on the increased illness burden of COVID-19 among unvaccinated first responders. From January to September 2021, first responders contributed to weekly active surveillance for COVID-19-like illness (CLI). Self-collected respiratory specimens collected weekly, irrespective of symptoms, and at the onset CLI were tested by Reverse Transcription Polymerase Chain Reaction (RT-PCR) assay for SARSCoV-2. Among 1415 first responders, 17% were LEOs, 68% firefighters, and 15% had other first responder occupations. Unvaccinated (41%) compared to fully vaccinated (59%) first responders were less likely to believe COVID-19 vaccines are very or extremely effective (17% versus 54%) or very or extremely safe (15% versus 54%). From January through September 2021, among unvaccinated LEOs, the incidence of COVID-19 was 11.9 per 1,000 person-weeks (95%CI=7.0-20.1) compared to only 0.6 (95%CI=0.2-2.5) among vaccinated LEOs. Incidence of COVID-19 was also higher among unvaccinated firefighters (9.0 per 1,000 person-weeks; 95%CI=6.4-12.7) compared to those vaccinated (1.8 per 1,000; 95%CI=1.1-2.8). Once they had laboratory-confirmed COVID-19, unvaccinated first responders were sick for a mean+/-SD of 14.7+/-21.7 days and missed a mean of 38.0+/-46.0 hours of work. These findings suggest that state and local governments with large numbers of unvaccinated first responders may face major disruptions in their workforce due to COVID-19 illness. Copyright The copyright holder for this preprint is the author/funder, who has granted medRxiv a license to display the preprint in perpetuity. It is made available under a CC-BY-NC-ND 4.0 International license.

Immunization Information Systems are confidential computerized population-based systems that collect data from vaccination providers on individual vaccinations administered along with limited patient-level characteristics. Through a data use agreement, Centers for Disease Control and Prevention obtains the individual-level data and aggregates the number of vaccinations for geographical statistical areas defined by the US Census Bureau (counties or equivalent statistical entities) for each vaccine included in system. Currently, 599 counties, covering 11 states, collect and report data using a uniform protocol. We combine these data with inter-decennial population counts from the Population Estimates Program in the US Census Bureau and several covariates from a variety of sources to develop model-based estimates for each of the 3,142 counties in 50 states and the District of Columbia and then aggregate to the state and national levels. We use a hierarchical Bayesian model and Markov Chain Monte Carlo methods to obtain draws from the posterior predictive distribution of the vaccination rates. We use posterior predictive checks and cross-validation to assess the goodness of fit and to validate the models. We also compare the model-based estimates to direct estimates from the National Immunization Surveys. © 2023 The Author(s). Published by Oxford University Press on behalf of the American Association for Public Opinion Research. All rights reserved.

BACKGROUND: Immunocompromised (IC) persons are at increased risk for severe COVID-19 outcomes and are less protected by 1-2 COVID-19 vaccine doses than are immunocompetent (non-IC) persons. We compared vaccine effectiveness (VE) against medically attended COVID-19 of 2-3 mRNA and 1-2 viral-vector vaccine doses between IC and non-IC adults. METHODS: Using a test-negative design among eight VISION Network sites, VE against laboratory-confirmed COVID-19-associated emergency department (ED) or urgent care (UC) events and hospitalizations from 26 August-25 December 2021 was estimated separately among IC and non-IC adults and among specific IC condition subgroups. Vaccination status was defined using number and timing of doses. VE for each status (versus unvaccinated) was adjusted for age, geography, time, prior positive test result, and local SARS-CoV-2 circulation. RESULTS: We analyzed 8,848 ED/UC events and 18,843 hospitalizations among IC patients and 200,071 ED/UC events and 70,882 hospitalizations among non-IC patients. Among IC patients, 3-dose mRNA VE against ED/UC (73% [95% CI: 64-80]) and hospitalization (81% [95% CI: 76-86]) was lower than that among non-IC patients (ED/UC: 94% [95% CI: 93-94]; hospitalization: 96% [95% CI: 95-97]). Similar patterns were observed for viral-vector vaccines. Transplant recipients had lower VE than other IC subgroups. CONCLUSIONS: During B.1.617.2 (Delta) variant predominance, IC adults received moderate protection against COVID-19-associated medical events from three mRNA doses, or one viral-vector dose plus a second dose of any product. However, protection was lower in IC versus non-IC patients, especially among transplant recipients, underscoring the need for additional protection among IC adults.

Background. Studies have reported that prior-season influenza vaccination is associated with higher risk of clinical influenza infection among vaccinees in a given season. Understanding the underlying causes requires consideration of within-season waning and recent infection. Methods. Using the US Flu Vaccine Effectiveness (VE) Network data over 8 influenza seasons (2011-2012 to 2018-2019), we estimated the effect of prior-season vaccination on the odds of clinical infection in a given season, after accounting for waning vaccine protection using regression methods. We adjusted for potential confounding by recent clinical infection using inverse-probability weighting. We investigated theoretically whether unmeasured subclinical infection in the prior season, which is more likely in the non-repeat vaccinees, could explain the repeat vaccination effect. Results. Repeat vaccinees vaccinated earlier in a season by one week. After accounting for waning VE, repeat vaccinees were still more likely to test positive for influenza A(H3N2) (OR=1.11, 95% CI:1.02-1.21) but not for influenza B (OR=1.03, 95% CI:0.89-1.18) or A(H1N1) (OR=1.03, 95% CI:0.90-1.19) compared to those vaccinated in the given season only. Recent clinical infection with the homologous (sub)type protected against clinical infection with A(H3N2) or B. Individuals with clinical infection in one season had 1.11 (95% CI:1.03-1.19) times the odds of switching vaccination status in the following season. Adjusting for recent clinical infections did not strongly influence the estimated effect of prior-season vaccination. Adjusting for subclinical infection could theoretically attenuate this effect. Conclusion. Waning protection and recent clinical infection were insufficient to explain observed reduced VE in repeat vaccinees with a test-negative design. Copyright The copyright holder for this preprint is the author/funder, who has granted medRxiv a license to display the preprint in perpetuity. It is made available under a CC-BY-NC-ND 4.0 International license.

Background: We estimated SARS-CoV-2 Delta and Omicron-specific effectiveness of 2 and 3 mRNA COVID-19 vaccine doses in adults against symptomatic illness in US outpatient settings. Method(s): Between October 1, 2021, and February 12, 2022, research staff consented and enrolled eligible participants who had fever, cough, or loss of taste or smell and sought outpatient medical care or clinical SARS-CoV-2 testing within 10 days of illness onset. Using the test-negative design, we compared the odds of receiving 2 or 3 mRNA COVID-19 vaccine doses among SARS-CoV-2 cases versus controls using logistic regression. Regression models were adjusted for study site, age, onset week, and prior SARS-CoV-2 infection. Vaccine effectiveness (VE) was calculated as (1 - adjusted odds ratio) x 100%. Result(s): Among 3847 participants included for analysis, 574 (32%) of 1775 tested positive for SARS-CoV-2 during the Delta predominant period and 1006 (56%) of 1794 participants tested positive during the Omicron predominant period. When Delta predominated, VE against symptomatic illness in outpatient settings was 63% (95% CI: 51% to 72%) among mRNA 2-dose recipients and 96% (95% CI: 93% to 98%) for 3-dose recipients. When Omicron predominated, VE was 21% (95% CI: -6% to 41%) among 2-dose recipients and 62% (95% CI: 48% to 72%) among 3-dose recipients. Conclusion(s): In this adult population, 3 mRNA COVID-19 vaccine doses provided substantial protection against symptomatic illness in outpatient settings when the Omicron variant became the predominant cause of COVID-19 in the U.S. These findings support the recommendation for a 3rd mRNA COVID-19 vaccine dose. Copyright The copyright holder for this preprint is the author/funder, who has granted medRxiv a license to display the preprint in perpetuity. This article is a US Government work. It is not subject to copyright under 17 USC 105 and is also made available for use under a CC0 license.

Background: Immunocompromised (IC) persons are at increased risk for severe COVID-19 outcomes and are less protected by 1-2 COVID-19 vaccine doses than are immunocompetent (non-IC) persons. We compared vaccine effectiveness (VE) against medically attended COVID-19 of 2-3 mRNA and 1-2 viral-vector vaccine doses between IC and non-IC adults. Method(s): Using a test-negative design among eight VISION Network sites, VE against laboratory-confirmed COVID-19-associated emergency department (ED) or urgent care (UC) events and hospitalizations from 26 August-25 December 2021 was estimated separately among IC and non-IC adults and among specific IC condition subgroups. Vaccination status was defined using number and timing of doses. VE for each status (versus unvaccinated) was adjusted for age, geography, time, prior positive test result, and local SARS-CoV-2 circulation. Result(s): We analyzed 8,848 ED/UC events and 18,843 hospitalizations among IC patients and 200,071 ED/UC events and 70,882 hospitalizations among non-IC patients. Among IC patients, 3-dose mRNA VE against ED/UC (73% [95% CI: 64-80]) and hospitalization (81% [95% CI: 76-86]) was lower than that among non-IC patients (ED/UC: 94% [95% CI: 93-94]; hospitalization: 96% [95% CI: 95-97]). Similar patterns were observed for viral-vector vaccines. Transplant recipients had lower VE than other IC subgroups. Conclusion(s): During B.1.617.2 (Delta) variant predominance, IC adults received moderate protection against COVID-19-associated medical events from three mRNA doses, or one viral-vector dose plus a second dose of any product. However, protection was lower in IC versus non-IC patients, especially among transplant recipients, underscoring the need for additional protection among IC adults. Copyright The copyright holder for this preprint is the author/funder, who has granted medRxiv a license to display the preprint in perpetuity. This article is a US Government work. It is not subject to copyright under 17 USC 105 and is also made available for use under a CC0 license.

BACKGROUND: Understanding the usefulness of additional COVID-19 vaccine doses-particularly given varying disease incidence-is needed to support public health policy. We characterize the benefits of COVID-19 booster doses using number needed to vaccinate (NNV) to prevent one COVID-19-associated hospitalization or emergency department encounter. METHODS: We conducted a retrospective cohort study of immunocompetent adults at five health systems in four U.S. states during SARS-CoV-2 Omicron BA.1 predominance (December 2021-February 2022). Included patients completed a primary mRNA COVID-19 vaccine series and were either eligible to or received a booster dose. NNV were estimated using hazard ratios for each outcome (hospitalization and emergency department encounters), with results stratified by three 25-day periods and site. FINDINGS: 1,285,032 patients contributed 938 hospitalizations and 2076 emergency department encounters. 555,729 (43.2%) patients were aged 18-49 years, 363,299 (28.3%) 50-64 years, and 366,004 (28.5%) ≥65 years. Most patients were female (n = 765,728, 59.6%), White (n = 990,224, 77.1%), and non-Hispanic (n = 1,063,964, 82.8%). 37.2% of patients received a booster and 62.8% received only two doses. Median estimated NNV to prevent one hospitalization was 205 (range 44-615) and NNV was lower across study periods for adults aged ≥65 years (110, 46, and 88, respectively) and those with underlying medical conditions (163, 69, and 131, respectively). Median estimated NNV to prevent one emergency department encounter was 156 (range 75-592). INTERPRETATION: The number of patients needed to receive a booster dose was highly dependent on local disease incidence, outcome severity, and patient risk factors for moderate-to-severe disease. FUNDING: Funding was provided by the Centers for Disease Control and Prevention though contract 75D30120C07986 to Westat, Inc. and contract 75D30120C07765 to Kaiser Foundation Hospitals.

BACKGROUND: Emerging data suggest that second-generation influenza vaccines with higher hemagglutinin (HA) antigen content and/or different production methods may induce stronger antibody responses to HA than standard-dose egg-based influenza vaccines in adults. We compared antibody responses to high-dose egg-based inactivated (HD-IIV3), recombinant (RIV4), and cell culture-based (ccIIV4) vs standard-dose egg-based inactivated influenza vaccine (SD-IIV4) among health care personnel (HCP) aged 18-65 years in 2 influenza seasons (2018-2019, 2019-2020). METHODS: In the second trial season, newly and re-enrolled HCPs who received SD-IIV4 in season 1 were randomized to receive RIV4, ccIIV4, or SD-IIV4 or were enrolled in an off-label, nonrandomized arm to receive HD-IIV3. Prevaccination and 1-month-postvaccination sera were tested by hemagglutination inhibition (HI) assay against 4 cell culture propagated vaccine reference viruses. Primary outcomes, adjusted for study site and baseline HI titer, were seroconversion rate (SCR), geometric mean titers (GMTs), mean fold rise (MFR), and GMT ratios that compared vaccine groups to SD-IIV4. RESULTS: Among 390 HCP in the per-protocol population, 79 received HD-IIV3, 103 RIV4, 106 ccIIV4, and 102 SD-IIV4. HD-IIV3 recipients had similar postvaccination antibody titers compared with SD-IIV4 recipients, whereas RIV4 recipients had significantly higher 1-month-postvaccination antibody titers against vaccine reference viruses for all outcomes. CONCLUSIONS: HD-IIV3 did not induce higher antibody responses than SD-IIV4, but, consistent with previous studies, RIV4 was associated with higher postvaccination antibody titers. These findings suggest that recombinant vaccines rather than vaccines with higher egg-based antigen doses may provide improved antibody responses in highly vaccinated populations.

OBJECTIVES: We assessed BNT162b2 vaccine effectiveness (VE) against mild to moderate and severe coronavirus disease 2019 (COVID-19) in children and adolescents through the Omicron BA.4/BA.5 period. METHODS: Using VISION Network records from April 2021 to September 2022, we conducted a test-negative, case-control study assessing VE against COVID-19-associated emergency department/urgent care (ED/UC) encounters and hospitalizations using logistic regression, conditioned on month and site, adjusted for covariates. RESULTS: We compared 9800 ED/UC cases with 70 232 controls, and 305 hospitalized cases with 2612 controls. During Delta, 2-dose VE against ED/UC encounters at 12 to 15 years was initially 93% (95% confidence interval 89 to 95), waning to 77% (69% to 84%) after ≥150 days. At ages 16 to 17, VE was initially 93% (86% to 97%), waning to 72% (63% to 79%) after ≥150 days. During Omicron, VE at ages 12 to 15 was initially 64% (44% to 77%), waning to 13% (3% to 23%) after ≥150 days; at ages 16 to 17 VE was 31% (10% to 47%) during days 60 to 149, waning to 7% (-8 to 20%) after 150 days. A monovalent booster increased VE to 54% (40% to 65%) at ages 12 to 15 and 46% (30% to 58%) at ages 16 to 17. At ages 5 to 11, 2-dose VE was 49% (33% to 61%) initially and 41% (29% to 51%) after 150 days. During Delta, VE against hospitalizations at ages 12 to 17 was high (>97%), and at ages 16 to 17 remained 98% (73% to 100%) beyond 150 days; during Omicron, hospitalizations were too infrequent to precisely estimate VE. CONCLUSIONS: BNT162b2 protected children and adolescents against mild to moderate and severe COVID-19. VE was lower during Omicron predominance including BA.4/BA.5, waned after dose 2 but increased after a monovalent booster. Children and adolescents should receive all recommended COVID-19 vaccinations.

BACKGROUND: An infodemic is excess information, including false or misleading information, that spreads in digital and physical environments during a public health emergency. The COVID-19 pandemic has been accompanied by an unprecedented global infodemic that has led to confusion about the benefits of medical and public health interventions, with substantial impact on risk-taking and health-seeking behaviors, eroding trust in health authorities and compromising the effectiveness of public health responses and policies. Standardized measures are needed to quantify the harmful impacts of the infodemic in a systematic and methodologically robust manner, as well as harmonizing highly divergent approaches currently explored for this purpose. This can serve as a foundation for a systematic, evidence-based approach to monitoring, identifying, and mitigating future infodemic harms in emergency preparedness and prevention. OBJECTIVE: In this paper, we summarize the Fifth World Health Organization (WHO) Infodemic Management Conference structure, proceedings, outcomes, and proposed actions seeking to identify the interdisciplinary approaches and frameworks needed to enable the measurement of the burden of infodemics. METHODS: An iterative human-centered design (HCD) approach and concept mapping were used to facilitate focused discussions and allow for the generation of actionable outcomes and recommendations. The discussions included 86 participants representing diverse scientific disciplines and health authorities from 28 countries across all WHO regions, along with observers from civil society and global public health-implementing partners. A thematic map capturing the concepts matching the key contributing factors to the public health burden of infodemics was used throughout the conference to frame and contextualize discussions. Five key areas for immediate action were identified. RESULTS: The 5 key areas for the development of metrics to assess the burden of infodemics and associated interventions included (1) developing standardized definitions and ensuring the adoption thereof; (2) improving the map of concepts influencing the burden of infodemics; (3) conducting a review of evidence, tools, and data sources; (4) setting up a technical working group; and (5) addressing immediate priorities for postpandemic recovery and resilience building. The summary report consolidated group input toward a common vocabulary with standardized terms, concepts, study designs, measures, and tools to estimate the burden of infodemics and the effectiveness of infodemic management interventions. CONCLUSIONS: Standardizing measurement is the basis for documenting the burden of infodemics on health systems and population health during emergencies. Investment is needed into the development of practical, affordable, evidence-based, and systematic methods that are legally and ethically balanced for monitoring infodemics; generating diagnostics, infodemic insights, and recommendations; and developing interventions, action-oriented guidance, policies, support options, mechanisms, and tools for infodemic managers and emergency program managers.

IMPORTANCE: Recent SARS-CoV-2 Omicron variant sublineages, including BA.4 and BA.5, may be associated with greater immune evasion and less protection against COVID-19 after vaccination. OBJECTIVES: To evaluate the estimated vaccine effectiveness (VE) of 2, 3, or 4 doses of COVID-19 mRNA vaccination among immunocompetent adults during a period of BA.4 or BA.5 predominant circulation; and to evaluate the relative severity of COVID-19 in hospitalized patients across Omicron BA.1, BA.2 or BA.2.12.1, and BA.4 or BA.5 sublineage periods. DESIGN, SETTING, AND PARTICIPANTS: This test-negative case-control study was conducted in 10 states with data from emergency department (ED) and urgent care (UC) encounters and hospitalizations from December 16, 2021, to August 20, 2022. Participants included adults with COVID-19-like illness and molecular testing for SARS-CoV-2. Data were analyzed from August 2 to September 21, 2022. EXPOSURES: mRNA COVID-19 vaccination. MAIN OUTCOMES AND MEASURES: The outcomes of interest were COVID-19 ED or UC encounters, hospitalizations, and admission to the intensive care unit (ICU) or in-hospital death. VE associated with protection against medically attended COVID-19 was estimated, stratified by care setting and vaccine doses (2, 3, or 4 doses vs 0 doses as the reference group). Among hospitalized patients with COVID-19, demographic and clinical characteristics and in-hospital outcomes were compared across sublineage periods. RESULTS: During the BA.4 and BA.5 predominant period, there were 229 eligible ED and UC encounters among patients with COVID-19-like illness (median [IQR] age, 51 [33-70] years; 49 682 [60.4%] female patients), and 19 114 patients (23.2%) had test results positive for SARS-CoV-2; among 21 007 hospitalized patients (median [IQR] age, 71 [58-81] years; 11 209 [53.4%] female patients), 3583 (17.1 %) had test results positive for SARS-CoV-2. Estimated VE against hospitalization was 25% (95% CI, 17%-32%) for receipt of 2 vaccine doses at 150 days or more after receipt, 68% (95% CI, 50%-80%) for a third dose 7 to 119 days after receipt, and 36% (95% CI, 29%-42%) for a third dose 120 days or more (median [IQR], 235 [204-262] days) after receipt. Among patients aged 65 years or older who had received a fourth vaccine dose, VE was 66% (95% CI, 53%-75%) at 7 to 59 days after vaccination and 57% (95% CI, 44%-66%) at 60 days or more (median [IQR], 88 [75-105] days) after vaccination. Among hospitalized patients with COVID-19, ICU admission or in-hospital death occurred in 21.4% of patients during the BA.1 period vs 14.7% during the BA.4 and BA.5 period (standardized mean difference: 0.17). CONCLUSIONS AND RELEVANCE: In this case-control study of COVID-19 vaccines and illness, VE associated with protection against medically attended COVID-19 illness was lower with increasing time since last dose; estimated VE was higher after receipt of 1 or 2 booster doses compared with a primary series alone.

BACKGROUND: Data assessing protection conferred from COVID-19 mRNA vaccination and/or prior SARS-CoV-2 infection during Delta and Omicron predominance periods in the U.S. are limited. METHODS: This cohort study included persons ≥18 years who had ≥1 healthcare encounter across four health systems and had been tested for SARS-CoV-2 before August 26, 2021. COVID-19 mRNA vaccination and prior SARS-CoV-2 infection defined the exposure. Cox regression estimated hazard ratios (HRs) for the Delta and Omicron periods; protection was calculated as (1-HR)x100%. RESULTS: Compared to unvaccinated and previously uninfected persons, during Delta predominance, protection against COVID-19-associated hospitalizations was high for those 2- or 3-dose vaccinated and previously infected, 3-dose vaccinated alone, and prior infection alone (range:91%-97%, with overlapping 95% confidence intervals (95%CIs)); during Omicron predominance, estimates were lower (range:77%-90%). Protection against COVID-19-associated emergency department/urgent care (ED/UC) encounters during Delta predominance was high for those exposure groups (range:86%-93%); during Omicron predominance, protection remained high for those 3-dose vaccinated with or without a prior infection (76% (95%CI=67%-83%) and 71% (95%CI=67%-73%), respectively). CONCLUSIONS: COVID-19 mRNA vaccination and/or prior SARS-CoV-2 infection provided protection against COVID-19-associated hospitalizations and ED/UC encounters regardless of variant. Staying up-to-date with COVID-19 vaccination still provides protection against severe COVID-19 disease, regardless of prior infection.

Although severe COVID-19 illness and hospitalization are more common among older adults, children can also be affected (1). More than 3 million cases of COVID-19 had been reported among infants and children aged <5 years (children) as of December 2, 2022 (2). One in four children hospitalized with COVID-19 required intensive care; 21.2% of cases of COVID-19-related multisystem inflammatory syndrome in children (MIS-C) occurred among children aged 1-4 years, and 3.2% of MIS-C cases occurred among infants aged <1 year (1,3). On June 17, 2022, the Food and Drug Administration issued an Emergency Use Authorization (EUA) of the Moderna COVID-19 vaccine for children aged 6 months-5 years and the Pfizer-BioNTech COVID-19 vaccine for children aged 6 months-4 years. To assess COVID-19 vaccination coverage among children aged 6 months-4 years in the United States, coverage with ≥1 dose* and completion of the 2-dose or 3-dose primary vaccination series(†) were assessed using vaccine administration data for the 50 U.S. states and District of Columbia submitted from June 20 (after COVID-19 vaccine was first authorized for this age group) through December 31, 2022. As of December 31, 2022, ≥1-dose COVID-19 vaccination coverage among children aged 6 months-4 years was 10.1% and was 5.1% for series completion. Coverage with ≥1 dose varied by jurisdiction (range = 2.1% [Mississippi] to 36.1% [District of Columbia]) as did coverage with a completed series (range = 0.7% [Mississippi] to 21.4% [District of Columbia]), respectively. By age group, 9.7 % of children aged 6-23 months and 10.2% of children aged 2-4 years received ≥1 dose; 4.5% of children aged 6-23 months and 5.4% of children aged 2-4 years completed the vaccination series. Among children aged 6 months-4 years, ≥1-dose COVID-19 vaccination coverage was lower in rural counties (3.4%) than in urban counties (10.5%). Among children aged 6 months-4 years who received at least the first dose, only 7.0% were non-Hispanic Black or African American (Black), and 19.9% were Hispanic or Latino (Hispanic), although these demographic groups constitute 13.9% and 25.9% of the population, respectively (4). COVID-19 vaccination coverage among children aged 6 months-4 years is substantially lower than that among older children (5). Efforts are needed to improve vaccination coverage among children aged 6 months-4 years to reduce COVID-19-associated morbidity and mortality.

INTRODUCTION: In 2021, HHS Office of Minority Health and CDC developed a composite measure of social vulnerability called the Minority Health Social Vulnerability Index (MHSVI) to assess the needs of communities most vulnerable to COVID-19. The MHSVI extends the CDC Social Vulnerability Index with two new themes on healthcare access and medical vulnerability. This analysis examines COVID-19 vaccination coverage by social vulnerability using the MHSVI. METHODS: County-level COVID-19 vaccine administration data among persons aged ≥18 years reported to CDC from 12/14/20 to 01/31/22 were analyzed. U.S. counties from 50 states and DC were categorized into tertiles of vulnerability (low, moderate, and high) for the composite MHSVI measure and each of the 34 indicators. Vaccination coverage (≥1 dose, primary series completion, and receipt of a booster dose) was calculated by tertiles for the composite MHSVI measure and each indicator. RESULTS: Counties with lower per capita income, higher proportion of individuals with no high school diploma, living below poverty, ≥65 years of age, with a disability, and in mobile homes had lower vaccination uptake. However, counties with larger proportions of racial/ethnic minorities and individuals speaking English less than "very well" had higher coverage. Counties with fewer primary care physicians and greater medical vulnerabilities had lower ≥ 1 dose vaccination coverage. Furthermore, counties of high vulnerability had lower primary series completion and receipt of a booster dose. There were no clear patterns in COVID-19 vaccination coverage by tertiles for the composite measure. CONCLUSION: Results from the new components in the MHSVI identify needs to prioritize persons in counties with greater medical vulnerabilities and limited access to health care, who are at greater risk for adverse COVID-19 outcomes. Findings suggest that using a composite measure to characterize social vulnerability might mask disparities in COVID-19 vaccination uptake that would have otherwise been observed using specific indicators.

At its October 2022 meeting, the Advisory Committee on Immunization Practices* (ACIP) approved the Recommended Adult Immunization Schedule for Ages 19 Years or Older, United States, 2023. The 2023 adult immunization schedule summarizes ACIP recommendations, including several changes to the cover page, tables, notes, and appendix from the 2022 immunization schedule.(†) This schedule can be found on the CDC immunization schedule website (https://www.cdc.gov/vaccines/schedules). Health care providers are advised to use the cover page, tables, notes, and appendix together to determine recommended vaccinations for patient populations. This adult immunization schedule is recommended by ACIP (https://www.cdc.gov/vaccines/acip) and approved by CDC (https://www.cdc.gov), the American College of Physicians (https://www.acponline.org), the American Academy of Family Physicians (https://www.aafp.org), the American College of Obstetricians and Gynecologists (https://www.acog.org), the American College of Nurse-Midwives (https://www.midwife.org), the American Academy of Physician Associates (https://www.aapa.org), the American Pharmacists Association (https://www.pharmacist.com), and the Society for Healthcare Epidemiology of America (https://shea-online.org).

In October 2022, the Advisory Committee on Immunization Practices (ACIP) voted to approve the Recommended Adult Immunization Schedule for Ages 19 Years or Older, United States, 2023. The 2023 adult immunization schedule, available at www.cdc.gov/vaccines/schedules/hcp/imz/adult.html, summarizes ACIP recommendations in the cover page, tables, notes, and appendix (Figure). The full ACIP recommendations for each vaccine are available at www.cdc.gov/vaccines/hcp/acip-recs/index.html. The 2023 schedule has also been approved by the director of the Centers for Disease Control and Prevention (CDC) and by the American College of Physicians (www.acponline.org), the American Academy of Family Physicians (www.aafp.org), the American College of Obstetricians and Gynecologists (www.acog.org), the American College of Nurse-Midwives (www.midwife.org), the American Academy of Physician Associates (www.aapa.org), the American Pharmacists Association (www.pharmacist.com), and the Society for Healthcare Epidemiology of America (www.shea-online.org).

At its October 2022 meeting, the Advisory Committee on Immunization Practices* (ACIP) approved the Recommended Child and Adolescent Immunization Schedule for Ages 18 Years or Younger, United States, 2023. The 2023 child and adolescent immunization schedule, available on the CDC immunization schedule website (https://www.cdc.gov/vaccines/schedules), summarizes ACIP recommendations, including several changes from the 2022 immunization schedule(†) on the cover page, tables, notes, and appendix. Health care providers are advised to use the tables, notes, and appendix together to determine recommended vaccinations for patient populations. This immunization schedule is recommended by ACIP (https://www.cdc.gov/vaccines/acip) and approved by CDC (https://www.cdc.gov), the American Academy of Pediatrics (https://www.aap.org), the American Academy of Family Physicians (https://www.aafp.org), the American College of Obstetricians and Gynecologists (http://www.acog.org), the American College of Nurse-Midwives (https://www.midwife.org), the American Academy of Physician Associates (https://www.aapa.org), and the National Association of Pediatric Nurse Practitioners (https://www.napnap.org).

BACKGROUND: Current understanding of severe RSV infections in adults is limited by clinical under-recognition. We compared the prevalence, clinical characteristics, and outcomes of RSV infections vs influenza in adults hospitalized with acute respiratory illnesses in a prospective national surveillance network. METHODS: Hospitalized adults who met a standardized ARI case definition were prospectively enrolled across three respiratory seasons from hospitals participating across all sites of the U.S. Hospitalized Adult Influenza Vaccine Effectiveness Network (HAIVEN, 2016-2019). All participants were tested for RSV and influenza by RT-PCR. Multivariable logistic regression was used to test associations between laboratory-confirmed infection and characteristics and clinical outcomes. RESULTS: Among 10,311 hospitalized adults, 6% tested positive for RSV (n=622), 18.8% positive for influenza (n=1,940), and 75.1% negative for RSV and influenza (n=7,749). Congestive Heart Failure (CHF) or Chronic Obstructive Pulmonary Disease (COPD) was more frequent among adults with RSV than influenza (CHF: 37.3% vs. 28.8%, p<0.0001; COPD: 47.6% vs. 35.8%, p<0.0001). Patients with RSV more frequently had longer admissions [OR=1.38 (95% CI: 1.06-1.80) for stays >one week] and mechanical ventilation [OR=1.45 (95% CI: 1.09-1.93)] compared with influenza, but not compared to the influenza negative group [OR=1.03 (95% CI: 0.82-1.28); OR=1.17 (0.91-1.49), respectively.]. CONCLUSIONS: The prevalence of RSV across three recent respiratory illness seasons was considerable. Our findings suggest those with RSV might incur worse outcomes than influenza in hospitalized adults and frequently have pre-existing cardiopulmonary conditions. This study informs future vaccination strategies and underscores a need for RSV surveillance among adults experiencing severe ARI.

BACKGROUND: COVID-19 vaccination coverage remains lower in communities with higher social vulnerability. Factors such as SARS-CoV-2 exposure risk and access to health care are often correlated with social vulnerability and may therefore contribute to a relationship between vulnerability and observed vaccine effectiveness (VE). Understanding whether these factors impact VE could contribute to our understanding of real-world VE. METHODS: We used electronic health record data from seven health systems to assess vaccination coverage among patients with medically attended COVID-19-like illness. We then used a test-negative design to assess VE for 2- and 3-dose mRNA adult (≥18 years) vaccine recipients across Social Vulnerability Index (SVI) quartiles. SVI rankings were determined by geocoding patient addresses to census tracts; rankings were grouped into quartiles for analysis. RESULTS: In July 2021, primary series vaccination coverage was higher in the least vulnerable quartile than in the most vulnerable quartile (56% vs. 36%, respectively). In February 2022, booster dose coverage among persons who had completed a primary series was higher in the least vulnerable quartile than in the most vulnerable quartile (43% vs. 30%). VE among 2-dose and 3-dose recipients during the Delta and Omicron BA.1 periods of predominance was similar across SVI quartiles. CONCLUSIONS: COVID-19 vaccination coverage varied substantially by SVI. Differences in VE estimates by SVI were minimal across groups after adjusting for baseline patient factors. However, lower vaccination coverage among more socially vulnerable groups means that the burden of illness is still disproportionately borne by the most socially vulnerable populations.

During June-October 2022, the SARS-CoV-2 Omicron BA.5 sublineage accounted for most of the sequenced viral genomes in the United States, with further Omicron sublineage diversification through November 2022.* Bivalent mRNA vaccines contain an ancestral SARS-CoV-2 strain component plus an updated component of the Omicron BA.4/BA.5 sublineages. On September 1, 2022, a single bivalent booster dose was recommended for adults who had completed a primary vaccination series (with or without subsequent booster doses), with the last dose administered ≥2 months earlier (1). During September 13-November 18, the VISION Network evaluated vaccine effectiveness (VE) of a bivalent mRNA booster dose (after 2, 3, or 4 monovalent doses) compared with 1) no previous vaccination and 2) previous receipt of 2, 3, or 4 monovalent-only mRNA vaccine doses, among immunocompetent adults aged ≥18 years with an emergency department/urgent care (ED/UC) encounter or hospitalization for a COVID-19-like illness.(†) VE of a bivalent booster dose (after 2, 3, or 4 monovalent doses) against COVID-19-associated ED/UC encounters was 56% compared with no vaccination, 31% compared with monovalent vaccination only with last dose 2-4 months earlier, and 50% compared with monovalent vaccination only with last dose ≥11 months earlier. VE of a bivalent booster dose (after 2, 3, or 4 monovalent doses) against COVID-19-associated hospitalizations was 57% compared with no vaccination, 38% compared with monovalent vaccination only with last dose 5-7 months earlier, and 45% compared with monovalent vaccination only with last dose ≥11 months earlier. Bivalent vaccines administered after 2, 3, or 4 monovalent doses were effective in preventing medically attended COVID-19 compared with no vaccination and provided additional protection compared with past monovalent vaccination only, with relative protection increasing with time since receipt of the last monovalent dose. All eligible persons should stay up to date with recommended COVID-19 vaccinations, including receiving a bivalent booster dose. Persons should also consider taking additional precautions to avoid respiratory illness this winter season, such as masking in public indoor spaces, especially in areas where COVID-19 community levels are high.

COVID-19 vaccines are safe and effective for infants and young children, and on June 18, 2022, CDC recommended COVID-19 vaccination for infants and children (children) aged 6 months-4 years (1,2). As of November 9, 2022, based on administrative data reported to CDC,* 5.9% of children aged <2 years and 8.8% of children aged 2-4 years had received ≥1 dose. To better understand reasons for low coverage among children aged <5 years, CDC analyzed data from 4,496 National Immunization Survey-Child COVID Module (NIS-CCM) interviews conducted during July 1-29, 2022, to examine variation in receipt of ≥1 dose of COVID-19 vaccine and parental intent to vaccinate children aged 6 months-4 years by sociodemographic characteristics and by parental beliefs about COVID-19; type of vaccination place was also reported. Among children aged 6 months-4 years, 3.5% were vaccinated; 59.3% were unvaccinated, but the parent was open to vaccination; and 37.2% were unvaccinated, and the parent was reluctant to vaccinate their child. Openness to vaccination was higher among parents of Hispanic or Latino (Hispanic) (66.2%), non-Hispanic Black or African American (Black) (61.1%), and non-Hispanic Asian (Asian) (83.1%) children than among parents of non-Hispanic White (White) (52.9%) children and lower among parents of children in rural areas (45.8%) than among parents of children in urban areas (64.1%). Parental confidence in COVID-19 vaccine safety and receipt of a provider recommendation for COVID-19 vaccination were lower among unvaccinated than vaccinated children. COVID-19 vaccine recommendations from a health care provider, along with dissemination of information about the safety of COVID-19 vaccine by trusted persons, could increase vaccination coverage among young children.