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      Influenza, Updated COVID-19, and Respiratory Syncytial Virus Vaccination Coverage Among Adults — United States, Fall 2023

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          Summary What is already known about this topic? The Advisory Committee on Immunization Practices recommends that all adults receive influenza and COVID-19 vaccines, and those aged ≥60 years may receive respiratory syncytial virus (RSV) vaccine during the 2023–24 respiratory virus season. What is added by this report? By December 9, 2023, an estimated 42.2% and 18.3% of adults aged ≥18 years had received influenza and updated 2023–2024 COVID-19 vaccine, respectively; 17.0% of adults aged ≥60 years had received RSV vaccine. Many adults who had not received the vaccines reported being open to vaccination. What are the implications for public health practice? Strong provider recommendations for and offers of vaccination could increase influenza, COVID-19, and RSV vaccination coverage. Immunization programs and vaccination partners might benefit from using these within-season data to understand vaccination patterns in their jurisdictions to strengthen vaccination activities. Abstract During the 2023–24 respiratory virus season, the Advisory Committee on Immunization Practices recommends influenza and COVID-19 vaccines for all persons aged ≥6 months, and respiratory syncytial virus (RSV) vaccine is recommended for persons aged ≥60 years (using shared clinical decision-making), and for pregnant persons. Data from the National Immunization Survey-Adult COVID Module, a random-digit–dialed cellular telephone survey of U.S. adults aged ≥18 years, are used to monitor influenza, COVID-19, and RSV vaccination coverage. By December 9, 2023, an estimated 42.2% and 18.3% of adults aged ≥18 years reported receiving an influenza and updated 2023–2024 COVID-19 vaccine, respectively; 17.0% of adults aged ≥60 years had received RSV vaccine. Coverage varied by demographic characteristics. Overall, approximately 27% and 41% of adults aged ≥18 years and 53% of adults aged ≥60 years reported that they definitely or probably will be vaccinated or were unsure whether they would be vaccinated against influenza, COVID-19, and RSV, respectively. Strong provider recommendations for and offers of vaccination could increase influenza, COVID-19, and RSV vaccination coverage. Immunization programs and vaccination partners are encouraged to use these data to understand vaccination patterns and attitudes toward vaccination in their jurisdictions to guide planning, implementation, strengthening, and evaluation of vaccination activities. Introduction Influenza, SARS-CoV-2, and respiratory syncytial virus (RSV) typically circulate in the United States during the fall through early spring each year, causing epidemics of respiratory illness, although patterns of influenza and RSV transmission shifted during the COVID-19 pandemic ( 1 – 3 ). Certain groups, including older adults (those aged ≥65 years), persons with chronic conditions, and racial and ethnic minority populations, have experienced disproportionate influenza-, COVID-19–, and RSV-associated morbidity and mortality ( 1 – 4 ). Since 2010, the Advisory Committee on Immunization Practices (ACIP) has recommended routine annual influenza vaccination for all persons aged ≥6 months who do not have contraindications ( 1 ). On September 12, 2023, ACIP recommended updated 2023–2024 COVID-19 vaccination for all persons aged ≥6 months to help protect against currently circulating SARS-CoV-2 variants ( 2 ). In June 2023, ACIP recommended that adults aged ≥60 years may receive a single dose of RSV vaccine, using shared clinical decision-making, which is the first time a vaccine for prevention of RSV-associated respiratory disease has been recommended* ( 3 ). CDC monitors coverage with these vaccines and makes these data available during the respiratory season for use in planning vaccination activities. Methods Data Collection The National Immunization Survey-Adult COVID Module (NIS-ACM) is a random-digit–dialed cellular telephone survey of adults aged ≥18 years in all 50 states, the District of Columbia, and selected local areas and U.S. territories. Data are weighted to represent the noninstitutionalized U.S. population. † The survey includes questions about receipt of COVID-19, influenza, and RSV vaccines, vaccination intent, sociodemographic characteristics, and behavioral and social drivers of COVID-19 vaccination. Respondents are asked if they have received a COVID-19 or RSV vaccine or have received an influenza vaccine since July 1, 2023, and for affirmative responses, the month and year of vaccination. § Those reporting receipt of any COVID-19 vaccine since September 14, 2023, are considered to be vaccinated with the updated 2023–2024 COVID-19 vaccine, because this was the only COVID-19 vaccine authorized in the United States after that date. Data Analysis Data collected during September 24–December 9, 2023, are included in this analysis. ¶ Estimates of coverage (percentage of the population vaccinated) with influenza, COVID-19, and RSV vaccines were calculated for weekly data collection periods using a nondecreasing composite estimation procedure that uses data from completed interviews from the current week combined with data from all previous weeks ( 5 ). Estimates for vaccination intent are based on interviews conducted each respective week and are adjusted to the cumulative vaccination coverage estimate for that week. Influenza and COVID-19 vaccination coverage is estimated among adults aged ≥18 years, and RSV vaccination coverage estimates are restricted to respondents aged ≥60 years. Differences among estimates were determined using t-tests with p<0.05 considered statistically significant. This activity was reviewed by CDC, deemed not research, and was conducted consistent with applicable federal law and CDC policy.** Results Overall Vaccination Coverage and Intent As of December 9, 2023, estimated influenza and updated COVID-19 vaccination coverage among adults aged ≥18 years was 42.2% and 18.3%, respectively; estimated RSV vaccination coverage among all adults aged ≥60 years was 17.0% and among those with chronic health conditions †† was 21.4% (Figure 1) (Supplementary Table, https://stacks.cdc.gov/view/cdc/136452). From September 24 through December 9, the percentage of adults who reported being unvaccinated, but who definitely will get vaccinated, decreased over time as vaccination coverage increased, from 33.2% to 9.4% for influenza and from 28.2% to 14.1% for COVID-19 vaccines. The decrease was less for RSV vaccine (from 20.9% to 14.1%). Throughout the study period, the proportion of adults who were unvaccinated and reported they probably or definitely would not get vaccinated was lowest for RSV, whereas the proportion who were unvaccinated and reported they probably would get vaccinated or were unsure was highest for RSV. FIGURE 1 Weekly influenza (A), updated COVID-19 (B), and respiratory syncytial virus (C) vaccination status* and vaccination intent † among adults § — National Immunization Survey-Adult COVID Module, United States, September 24–December 9, 2023 Abbreviation: RSV = respiratory syncytial virus. * Estimates of vaccination coverage were calculated for December 3–9, 2023 using a nondecreasing composite estimation procedure that uses data from all completed interviews during September 24–December 9, 2023: influenza (168,899), COVID-19 (168,669), and RSV (62,816). † Estimates for vaccination intent are based on interviews conducted during December 3–9, 2023, and were adjusted to the cumulative vaccination coverage estimate for that week: influenza (14,562), COVID-19 (14,539), and RSV (5,258). Estimates for vaccination intent are not shown for groups with sample size <30. § Estimates for influenza and COVID-19 vaccination coverage and vaccination intent are among adults aged ≥18 years. Estimates for RSV vaccination coverage and intent are among adults aged ≥60 years. This figure is a bar chart illustrating the weekly influenza, updated COVID-19, and respiratory syncytial virus vaccination status and vaccination intent among adults from the National Immunization Survey-Adult COVID Module in the United States during September 24–December 9, 2023. Vaccination Coverage and Intent by Demographic Characteristics and Jurisdiction Coverage with all vaccines was lowest among uninsured persons. Coverage and intent to be vaccinated increased with age and were higher among adults living in urban and suburban areas compared with those living in rural areas (Figure 2). Influenza vaccination coverage was higher among non-Hispanic White (White) and non-Hispanic Asian (Asian) adults than among most other racial and ethnic groups. However, the percentage of persons reporting that they probably or definitely will not get an influenza vaccination was similar among White adults (32.2%) and Black or African American (Black) adults (32.2%) and was lower among Hispanic or Latino (Hispanic) adults (24.0%). Updated COVID-19 and RSV vaccination coverage was higher among White adults than among most other racial and ethnic groups. However, a higher percentage of White adults reported that they probably or definitely will not receive a COVID-19 vaccine (43.2%) than did Black (31.3%) and Hispanic (34.7%) adults. Similarly, a higher percentage of White adults reported that they probably or definitely will not receive an RSV vaccine (32.5%) than did Black (15.3%) and Hispanic (19.3%) adults. Coverage with all vaccines varied by jurisdiction, ranging from 15.6% to 54.8% for influenza vaccine, from 2.4% to 35.6% for updated COVID-19 vaccine, and from 1.9% to 32.4% for RSV vaccine (Table). FIGURE 2 Influenza (A), updated COVID-19 (B), and respiratory syncytial virus (C) vaccination status* and vaccination intent † among adults, § by demographic characteristics ¶ — National Immunization Survey-Adult COVID Module, United States, December 3–9, 2023 Abbreviations: AI/AN = American Indian or Alaska Native; NH/OPI = Native Hawaiian or other Pacific Islander; RSV = respiratory syncytial virus. * Estimates of vaccination coverage were calculated for December 3–9, 2023 using a nondecreasing composite estimation procedure that uses data from all completed interviews during September 24–December 9, 2023: influenza (168,899), COVID-19 (168,669), and RSV (62,816). † Estimates for vaccination intent are based on interviews conducted during December 3–9, 2023, and were adjusted to the cumulative vaccination coverage estimate for that week: influenza (14,562), COVID-19 (14,539), and RSV (5,258). Estimates for vaccination intent are not shown for groups with sample size <30. § Estimates for influenza and COVID-19 vaccination coverage and vaccination intent are among adults aged ≥18 years. Estimates for RSV vaccination coverage and intent are among adults aged ≥60 years. ¶ Persons of Hispanic or Latino (Hispanic) origin might be of any race but are categorized as Hispanic; all racial groups are non-Hispanic. This figure is a bar chart illustrating the influenza, updated COVID-19, and respiratory syncytial virus vaccination status and vaccination intent among adults, by demographic characteristic, from the National Immunization Survey-Adult COVID Module in the United States during December 3–9, 2023. TABLE Coverage with influenza, updated COVID-19, and respiratory syncytial virus vaccines among adults,* by jurisdiction — National Immunization Survey-Adult COVID Module, United States, September 24–December 9, 2023 Jurisdiction Influenza COVID-19 RSV Cumulative unweighted no. % Vaccinated (95% CI)† Cumulative unweighted no. % Vaccinated (95% CI)† Cumulative unweighted no. % Vaccinated (95% CI)† Alabama 4,015 39.1 (35.4–42.8) 4,010 11.4 (9.3–13.4) 1,740 12.1 (8.4–15.7) Alaska 2,079 39.7 (35.3–44.2) 2,075 16.0 (13.0–19.0) 734 21.3 (16.1–26.6) Arizona 5,023 41.0 (37.5–44.5) 5,017 17.7 (15.4–20.1) 2,129 22.0 (17.4–26.6) Arkansas 2,599 42.2 (37.0–47.3) 2,591 14.5 (11.1–17.8) 1,037 14.7 (9.7–19.8) California 4,232 44.9 (40.6–49.2) 4,227 20.0 (16.8–23.1) 1,300 16.4 (10.5–22.3) Colorado 3,686 49.1 (45.0–53.3) 3,680 25.7 (22.3–29.2) 1,308 32.4 (25.9–39.0) Connecticut 1,235 47.0 (39.2–54.8) 1,233 23.6 (16.1–31.0) 212 24.1 (11.1–37.1) Delaware 2,530 51.2 (43.9–58.6) 2,527 23.1 (17.7–28.6) 1,194 17.2 (12.6–21.8) District of Columbia 4,307 52.9 (49.2–56.5) 4,304 35.6 (32.2–38.9) 1,291 20.7 (16.3–25.2) Florida 2,045 36.0 (30.0–41.9) 2,043 10.9 (7.8–14.1) 733 20.7 (13.0–28.4) Georgia 1,132 33.3 (25.3–41.3) 1,132 11.2 (5.1–17.3) 222 9.4 (5.2–13.7) Hawaii 3,323 46.1 (42.0–50.1) 3,319 20.1 (17.2–22.9) 1,421 19.2 (14.9–23.5) Idaho 1,474 34.8 (29.7–39.9) 1,472 16.5 (12.9–20.2) 502 21.0 (13.9–28.2) Illinois 7,190 48.0 (44.9–51.2) 7,175 24.6 (22.0–27.2) 2,662 20.3 (16.7–23.8) Indiana 2,678 39.5 (35.7–43.3) 2,671 16.8 (13.9–19.6) 1,003 14.5 (11.2–17.9) Iowa 1,510 46.1 (38.3–53.9) 1,509 26.8 (18.7–34.9) 583 22.9 (7.3–38.5) Kansas 2,875 44.7 (39.6–49.7) 2,871 20.0 (16.1–23.8) 960 22.4 (15.0–29.8) Kentucky 2,290 39.6 (32.6–46.7) 2,287 14.8 (8.8–20.7) 804 22.9 (7.7–38.2) Louisiana 3,719 36.8 (33.0–40.5) 3,713 10.1 (8.0–12.1) 1,542 13.8 (10.4–17.2) Maine 4,291 49.2 (42.6–55.9) 4,287 28.8 (22.7–34.8) 1,949 18.0 (11.7–24.4) Maryland 2,263 46.7 (41.2–52.2) 2,261 24.7 (17.7–31.7) 471 29.3 (17.2–41.3) Massachusetts 4,696 50.7 (47.5–54.0) 4,689 28.4 (25.8–31.0) 1,764 23.9 (18.7–29.1) Michigan 1,080 43.6 (35.4–51.7) 1,079 18.1 (12.2–23.9) 226 13.8 (5.2–22.4) Minnesota 3,154 48.0 (44.6–51.4) 3,149 31.5 (28.4–34.5) 1,316 19.3 (15.2–23.4) Mississippi 2,663 32.2 (27.9–36.5) 2,663 7.3 (4.9–9.8) 1,106 10.8 (6.0–15.6) Missouri 1,211 43.3 (34.9–51.7) 1,213 21.1 (14.4–27.7) 315 14.1 (2.8–25.3) Montana 3,301 39.4 (34.8–44.0) 3,292 20.9 (16.9–24.8) 1,510 17.1 (12.0–22.2) Nebraska 1,990 47.9 (40.7–55.2) 1,986 18.7 (12.5–24.9) 715 20.7 (10.4–31.0) Nevada 4,243 34.6 (31.7–37.4) 4,234 14.9 (12.9–16.9) 1,678 19.7 (15.9–23.5) New Hampshire 4,620 51.0 (47.4–54.7) 4,619 27.6 (24.6–30.7) 2,276 17.6 (14.6–20.7) New Jersey 3,780 45.7 (41.6–49.9) 3,770 19.1 (16.2–22.0) 1,350 14.6 (9.3–19.8) New Mexico 4,041 44.5 (40.9–48.1) 4,034 19.8 (17.3–22.2) 1,596 23.3 (19.3–27.3) New York 5,101 43.0 (39.7–46.2) 5,093 16.3 (14.3–18.4) 1,419 10.8 (8.2–13.5) North Carolina 4,240 43.9 (40.3–47.4) 4,234 18.3 (15.6–21.0) 1,618 16.0 (12.4–19.6) North Dakota 1,880 43.9 (39.5–48.2) 1,877 17.7 (14.6–20.8) 684 16.8 (10.4–23.2) Ohio 1,148 44.1 (36.5–51.7) 1,148 17.5 (12.2–22.7) 206 19.9 (9.3–30.5) Oklahoma 4,872 39.8 (36.7–42.9) 4,866 13.6 (11.7–15.5) 1,938 17.3 (13.9–20.8) Oregon 3,080 40.8 (37.1–44.5) 3,078 25.0 (21.6–28.5) 1,200 20.3 (15.8–24.7) Pennsylvania 8,446 43.4 (40.8–46.0) 8,432 19.8 (17.8–21.7) 3,217 14.4 (10.3–18.6) Puerto Rico 4,742 28.3 (25.8–30.8) 4,735 5.3 (4.2–6.4) 1,911 4.1 (2.3–6.0) Rhode Island 894 44.4 (36.6–52.2) 895 27.0 (19.1–35.0) 138 10.9 (2.0–19.7) South Carolina 2,951 42.5 (36.6–48.3) 2,955 16.7 (11.9–21.4) 1,285 10.1 (7.3–12.9) South Dakota 3,794 49.4 (45.5–53.3) 3,790 20.0 (17.4–22.6) 1,711 15.5 (12.2–18.9) Tennessee 855 35.6 (27.7–43.4) 853 11.4 (5.8–17.0) 183 8.8 (2.4–15.3) Texas 9,153 40.1 (34.9–45.4) 9,136 15.2 (11.0–19.4) 2,964 14.6 (10.2–19.0) U.S. Virgin Islands 1,782 15.6 (12.5–18.6) 1,784 2.4 (1.5–3.3) 876 1.9 (0.9–2.9) Utah 854 41.2 (33.7–48.7) 852 15.0 (9.7–20.3) 175 19.9 (4.4–35.4) Vermont 831 54.8 (44.9–64.8) 831 32.0 (24.9–39.0) 164 21.8 (10.5–33.0) Virginia 5,900 47.5 (45.0–50.1) 5,890 22.4 (20.5–24.3) 2,034 18.5 (15.5–21.5) Washington 1,445 41.5 (35.0–48.0) 1,440 21.7 (15.9–27.6) 278 20.2 (12.0–28.4) West Virginia 1,886 44.8 (35.9–53.7) 1,888 16.4 (9.6–23.2) 771 7.7 (5.5–10.0) Wisconsin 2,690 46.4 (41.8–51.0) 2,684 23.7 (20.1–27.3) 1,054 14.3 (10.3–18.2) Wyoming 3,080 35.6 (32.3–38.8) 3,076 14.9 (12.7–17.0) 1,341 16.6 (12.8–20.5) Range across jurisdictions — 15.6–54.8 — 2.4–35.6 — 1.9–32.4 Abbreviation: RSV = respiratory syncytial virus. * Estimates presented for influenza and COVID-19 vaccination are among adults aged ≥18 years. Estimates for RSV vaccination are among adults aged ≥60 years. Estimates of vaccination coverage were calculated for December 3–9, 2023 using a nondecreasing composite estimation procedure, which uses data collected from all completed interviews during September 24–December 9, 2023: influenza (168,899), COVID-19 (168,669), and RSV (62,816). † Weighted percentage. Discussion As of December 9, 2023, self-reported coverage with influenza, updated COVID-19, and RSV vaccines among U.S. adults was low, particularly for updated COVID-19 and RSV vaccines. RSV vaccination coverage was low even among persons with chronic conditions who are at highest risk for severe RSV disease and might benefit from vaccination. As of mid-November, influenza vaccination coverage was approximately 2.5 percentage points lower than it was at the same time during the 2022–23 influenza season ( 6 ). Approximately 41% of all adults and 53% of adults aged ≥60 years were unvaccinated but reported that they definitely or probably plan to receive or are unsure about receiving updated COVID-19 and RSV vaccines, respectively, suggesting they are open to vaccination. A health care provider recommendation for and offer of vaccination are strongly associated with vaccination ( 7 ). A previous report found that unvaccinated adults who were open to receiving a bivalent COVID-19 vaccine had not yet done so mainly because of concerns about side effects, being too busy, or just had not gotten around to getting vaccinated ( 8 ). Making vaccination available in provider offices, pharmacies, workplaces, and other convenient locations at convenient times, along with a strong provider recommendation for vaccination, could increase vaccination coverage, particularly for RSV, which is recommended on the basis of shared clinical decision-making between a patient and provider ( 3 ). Despite disparities in vaccination coverage by race and ethnicity, when responses indicating the person is open to vaccination are included, the potential vaccination coverage that could be achieved for Hispanic, Black, and Asian adults is similar to or higher than that for White adults. Programmatic measures that helped reduce disparities in coverage with the primary series of COVID-19 vaccine, such as making vaccines available free of charge, use of trusted messengers, and bringing vaccines into communities through nontraditional settings (e.g., local libraries and local businesses such as barber shops and restaurants) §§ ( 4 , 9 ), might increase equitable access to vaccination and decrease disparities for these currently recommended vaccines. CDC is partnering with community-based organizations, health care providers, and other trusted messengers to build vaccine confidence and awareness, including through the Partnering for Vaccine Equity program. ¶¶ CDC is also working to expand COVID-19 vaccine access to all through the Bridge Access Program, which provides COVID-19 vaccines for adults without health insurance and adults whose insurance does not cover all COVID-19 vaccine costs. Public health safety net and pharmacy locations offering influenza and COVID-19 vaccines, including COVID-19 vaccines through the Bridge Access Program, are available at https://www.vaccines.gov. Communication campaigns,*** such as the “Wild to Mild” and “Get My Flu Shot” influenza vaccine campaign and the “Everything” broad respiratory virus communication initiative, include various materials and resources to promote vaccination, including to persons who are disproportionately affected by disease. Finally, CDC has developed health care provider toolkits to empower providers with knowledge to confidently recommend vaccination. ††† CDC makes vaccination coverage estimates rapidly available during the respiratory virus season. §§§ , ¶¶¶ In addition to data from the NIS-ACM, vaccination data are available from multiple sources and include coverage among children, pregnant persons, Medicare beneficiaries, and national projected vaccination in pharmacies and medical offices. Jurisdiction-level estimates of COVID-19 vaccination coverage and intent stratified by demographic factors, behavioral and social drivers of vaccination, and barriers to vaccination are available.**** CDC’s COVID-19 Vaccination Geographic Information System Mapping Tool, designed with feedback from several local health departments, provides web maps where jurisdiction-level data including demographic characteristics and social determinants of health can be displayed along with vaccine confidence and vaccination coverage. †††† End-of-season influenza vaccination coverage estimates for children and adults since the 2010–11 influenza season, nationally and by state, are available on FluVaxView. §§§§ Limitations The findings in this report are subject to at least three limitations. First, response rates for NIS-ACM were relatively low (<25%). Data were weighted to mitigate possible bias resulting from incomplete sample frame (i.e., exclusion of households with no phone service or only landline telephones) or nonresponse, but some selection bias might persist. Second, all responses were self-reported; vaccination receipt, and month and year of receipt of most recent dose might be subject to recall or social desirability bias. Nonresponse and social desirability bias could result in overestimation of coverage. Third, the survey sampled noninstitutionalized U.S. adults; therefore, adults who were incarcerated or who live in long-term care facilities ¶¶¶¶ might not be represented in the sample. Implications for Public Health Practice Although influenza, updated COVID-19, and RSV vaccination has slowed for the 2023–24 respiratory season, vaccination is recommended to continue while viruses are circulating ( 1 – 3 ), and many unvaccinated persons continue to report intent to be vaccinated. Health care provider recommendations for and offers of vaccination are important to increasing vaccination coverage ( 7 ). Immunization programs and vaccination partners are encouraged to use CDC developed dashboards and tools, as well as other data sources available to them, such as immunization information systems, to identify undervaccinated populations and better understand vaccination patterns, attitudes and behaviors, and systemic barriers to vaccination in their jurisdiction to help tailor vaccination activities to improve coverage and health equity.

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          Use of Respiratory Syncytial Virus Vaccines in Older Adults: Recommendations of the Advisory Committee on Immunization Practices — United States, 2023

          Summary What is already known about this topic? Respiratory syncytial virus (RSV) causes substantial morbidity and mortality in older adults. In May 2023, the Food and Drug Administration approved the first two vaccines for prevention of RSV lower respiratory tract disease (LRTD) for use in adults aged ≥60 years. What is added by this report? For both vaccine products, vaccination with a single RSV vaccine dose demonstrated moderate to high efficacy in preventing symptomatic RSV-associated LRTD among adults aged ≥60 years. On June 21, 2023, the Advisory Committee on Immunization Practices recommended that persons aged ≥60 years may receive a single dose of RSV vaccine, using shared clinical decision-making. What are the implications for public health practice? RSV vaccination might prevent substantial morbidity in older adults at risk for severe RSV disease; postmarketing surveillance for safety and effectiveness will direct future guidance. Abstract Respiratory syncytial virus (RSV) is a cause of severe respiratory illness in older adults. In May 2023, the Food and Drug Administration approved the first vaccines for prevention of RSV-associated lower respiratory tract disease in adults aged ≥60 years. Since May 2022, the Advisory Committee on Immunization Practices (ACIP) Respiratory Syncytial Virus Vaccines Adult Work Group met at least monthly to review available evidence regarding the safety, immunogenicity, and efficacy of these vaccines among adults aged ≥60 years. On June 21, 2023, ACIP voted to recommend that adults aged ≥60 years may receive a single dose of an RSV vaccine, using shared clinical decision-making. This report summarizes the body of evidence considered for this recommendation and provides clinical guidance for the use of RSV vaccines in adults aged ≥60 years. RSV vaccines have demonstrated moderate to high efficacy in preventing RSV-associated lower respiratory tract disease and have the potential to prevent substantial morbidity and mortality among older adults; postmarketing surveillance will direct future guidance. Introduction In the United States, respiratory syncytial virus (RSV) causes seasonal epidemics of respiratory illness. Although the COVID-19 pandemic interrupted seasonal RSV circulation, the timing and number of incident cases of the 2022–23 fall and winter epidemic suggested a likely gradual return to prepandemic seasonality ( 1 ). Each season, RSV causes substantial morbidity and mortality in older adults, including lower respiratory tract disease (LRTD), hospitalization, and death. Incidence estimates vary widely and are affected by undertesting and potentially low sensitivity of standard diagnostic testing among adults ( 2 – 5 ). Most adult RSV disease cases occur among older adults with an estimated 60,000–160,000 hospitalizations and 6,000–10,000 deaths annually among adults aged ≥65 years ( 5 – 10 ). Adults with certain medical conditions, including chronic obstructive pulmonary disease, asthma, congestive heart failure, coronary artery disease, cerebrovascular disease, diabetes mellitus, and chronic kidney disease, are at increased risk for RSV-associated hospitalization ( 11 – 13 ), as are residents of long-term care facilities ( 14 ), and persons who are frail* or of advanced age (incidence of RSV-associated hospitalization among adults increases with age, with the highest rates among those aged ≥75 years) ( 6 , 15 ). RSV can also cause severe disease in persons with compromised immunity, including recipients of hematopoietic stem cell transplantation and patients taking immunosuppressive medications (e.g., for solid organ transplantation, cancer treatment, or other conditions) ( 16 , 17 ). In May 2023, the Food and Drug Administration (FDA) approved the first vaccines for prevention of RSV-associated LRTD in adults aged ≥60 years. RSVPreF3 (Arexvy, GSK) is a 1-dose (0.5 mL) adjuvanted (AS01E) recombinant stabilized prefusion F protein (preF) vaccine ( 18 ). RSVpreF (Abrysvo, Pfizer) is a 1-dose (0.5 mL) recombinant stabilized preF vaccine ( 19 ). Methods Since May 2022, CDC’s Advisory Committee on Immunization Practices (ACIP) RSV Vaccines Adult Work Group (Work Group) met at least monthly to review available evidence regarding the safety, immunogenicity, and efficacy of the GSK and Pfizer RSV vaccines among adults aged ≥60 years. A systematic review of published and unpublished evidence of the efficacy and safety of these vaccines among persons aged ≥60 years was conducted. The body of evidence consisted of one phase 3 randomized controlled trial and one combined phase 1 and 2 (phase 1/2) randomized controlled trial for each vaccine. The Work Group used the Grading of Recommendations, Assessment, Development and Evaluation (GRADE) approach to independently determine the certainty of evidence for outcomes related to each vaccine, rated on a scale of high to very low certainty. † In evaluating safety, the Work Group defined inflammatory neurologic events as cases of Guillain-Barré syndrome (GBS), chronic inflammatory demyelinating polyneuropathy, and acute central nervous system inflammation (e.g., transverse myelitis or acute disseminated encephalomyelitis [ADEM]) occurring within 42 days after vaccination. The Work Group then employed the Evidence to Recommendation Framework to guide its deliberations on recommendation for RSV vaccination, reviewing data on the public health problem, benefits and harms, value to the target population, acceptability to key stakeholders, feasibility, resource use, and equity. § Work Group conclusions regarding evidence for the use of RSV vaccines among adults aged ≥60 years were presented to ACIP at public meetings on February 23 and June 21, 2023 ( 10 , 15 ). Vaccine Efficacy and Safety GSK Vaccine Evaluated efficacy evidence for the GSK RSV vaccine consisted of data from one ongoing randomized, double-blind, placebo-controlled phase 3 clinical trial conducted in 17 countries and including 24,973 immunocompetent participants aged ≥60 years randomized 1:1 to receive 1 dose of vaccine (intervention group, 120 μg preF protein with AS01E adjuvant) or saline placebo (control group) ( 20 ). Efficacy findings were based on analyses of data collected during May 2021–March 2023, which included two complete RSV seasons for Northern Hemisphere participants and one complete RSV season for Southern Hemisphere participants. Efficacy analyses for season one spanned May 2021–April 2022, while efficacy analyses for season two spanned August 2022–March 2023; exact study-defined season dates were site-dependent. Mean time from vaccination to end of efficacy follow-up across both seasons was approximately 15 months per participant. The efficacy of 1 dose of the GSK vaccine in preventing symptomatic, laboratory-confirmed RSV-associated LRTD ¶ was 82.6% (96.95% CI = 57.9%–94.1%) during the first RSV season and 56.1% (95% CI = 28.2%–74.4%) during the second season (Table 1).** Efficacy of 1 dose over two seasons was 74.5% (97.5% CI = 60.0%–84.5%) in preventing RSV-associated LRTD and 77.5% (95% CI = 57.9%–89.0%) in preventing medically attended RSV-associated LRTD. †† The study was not powered to estimate efficacy against hospitalization (intervention group = one event; control group = five events), severe RSV illness requiring respiratory support (intervention group = one event; control group = five events), §§ or death (no events). ¶¶ TABLE 1 Efficacy of 1 dose of GSK respiratory syncytial virus RSVpreF3 vaccine against respiratory syncytial virus–associated disease among adults aged ≥60 years — multiple countries, 2021–2023 Efficacy evaluation period Vaccine efficacy against outcome* RSV-associated LRTD† RSV-associated medically attended LRTD§ Season 1¶ 82.6 (57.9–94.1)** 87.5 (58.9–97.6)†† Season 2§§ 56.1 (28.2–74.4)†† —¶¶ Combined seasons 1 and 2 (interim)*** 74.5 (60.0–84.5)††† 77.5 (57.9–89.0)†† Abbreviations: LRTD = lower respiratory tract disease; RSV = respiratory syncytial virus. * Manufacturer-calculated efficacy. Includes events >14 days after injection and person-time available from the manufacturer’s pivotal phase 3 trial. Estimates adjusted for participant age and region. † LRTD defined as two or more lower respiratory symptoms (new or increased sputum, cough, and dyspnea) or signs (new or increased wheezing, crackles or rhonchi detected during chest auscultation, respiratory rate ≥20 respirations per minute, low or decreased oxygen saturation [ 3.9” (>100 mm). For fever, grade 3 corresponded to a temperature >102.2°F (>39°C). For all other reactions, grade 3 corresponded to reactions that prevented normal, everyday activities. Grade 4 events were not defined in these trials. §§ Defined by the Advisory Committee on Immunization Practices Respiratory Syncytial Virus Vaccines Adult Work Group as GBS (including GBS variants), chronic inflammatory demyelinating polyneuropathy, or acute central nervous system inflammation (e.g., transverse myelitis or acute disseminated encephalomyelitis) occurring ≤42 days after vaccination. ¶¶ No inflammatory neurologic events were reported in either the phase 3 or phase 1/2 trials. However, across all RSVPreF3 trials inflammatory neurologic events were reported in three of 17,922 adults vaccinated with RSVPreF3. Events included one case of GBS in an open-label phase 3 clinical trial, and two cases of acute disseminated encephalomyelitis among participants in a randomized phase 3 study of coadministration of RSVPreF3 and standard dose seasonal influenza vaccine. Relative risk could not be calculated because neither trial had a placebo-controlled comparator group. Across all GSK vaccine clinical trials in older adults, inflammatory neurologic events were reported in three of 17,922 participants within 42 days after receipt of the GSK vaccine ( 23 ). All three events occurred in trials excluded from GRADE because of lack of an unvaccinated comparator arm. The reported cases included one case of GBS in a participant aged 78 years from Japan with symptom onset 9 days postvaccination in an open-label phase 3 clinical trial and two cases of ADEM among participants in a randomized phase 3 coadministration study ( 15 , 22 ). The two ADEM cases were reported in participants aged 71 years from the same site in South Africa after concomitant receipt of the GSK vaccine and standard dose seasonal influenza vaccine; symptom onset occurred 7 and 22 days postvaccination, and one case was fatal. In both ADEM cases, the diagnosis was based on symptoms and clinical findings only; diagnostic testing (including brain imaging, cerebrospinal fluid testing, and nerve conduction studies) was not performed, leading to uncertainty in the diagnoses. The investigator in the fatal case later revised the diagnosis from ADEM to hypoglycemia and dementia ( 15 , 22 ). Pfizer Vaccine Evaluated efficacy evidence for the Pfizer vaccine consisted of data from one ongoing, randomized, double-blind, placebo-controlled phase 3 clinical trial conducted in seven countries and including 36,862 immunocompetent participants aged ≥60 years randomized 1:1 to receive 1 dose of vaccine (intervention group, 120 μg preF protein) or placebo containing the same buffer ingredients as the vaccine but without active components (control group) ( 24 ). Efficacy findings were based on analyses of data collected during August 2021–January 2023, which included one complete RSV season for Northern and Southern Hemisphere participants and a partial second season for Northern Hemisphere participants only. Efficacy analyses for season one spanned August 2021–October 2022, while efficacy analyses for season two spanned July 2022–January 2023; exact study-defined season dates were site-dependent. Mean follow-up time from vaccination to end of efficacy follow-up across both seasons, including a gap in RSV surveillance between the first and second RSV seasons, was approximately 12 months per participant. Efficacy of 1 dose of the Pfizer vaccine in preventing symptomatic, laboratory-confirmed RSV-associated LRTD ††† was 88.9% (95% CI = 53.6%–98.7%) during the first RSV season and 78.6% (95% CI = 23.2%–96.1%) during the partial second season (Table 3). §§§ Efficacy of a single dose over two seasons was 84.4% (95% CI = 59.6%–95.2%) in preventing RSV-associated LRTD and 81.0% (95% CI = 43.5%–95.2%) in preventing medically attended RSV-associated LRTD. ¶¶¶ The study was not powered to estimate efficacy against hospitalization (intervention group = one event; control group = three events), severe RSV illness requiring respiratory support (intervention group = one event; control group = one event),**** or death (no events). †††† TABLE 3 Efficacy of 1 dose of Pfizer respiratory syncytial virus RSVpreF vaccine against respiratory syncytial virus–associated disease among adults aged ≥60 years — multiple countries, 2021–2023 Efficacy evaluation period Vaccine efficacy against outcome, % (95% CI)* RSV-associated LRTD† RSV-associated medically attended LRTD§ Season 1¶ 88.9 (53.6–98.7) 84.6 (32.0–98.3) Season 2 (interim)** 78.6 (23.2–96.1) —†† Combined seasons 1 and 2 (interim)§§ 84.4 (59.6–95.2) 81.0 (43.5–95.2) Abbreviations: LRTD = lower respiratory tract disease; LRTI = lower respiratory tract illness; RSV = respiratory syncytial virus. * Manufacturer-calculated efficacy. Includes events >14 days after injection and person-time available from the manufacturer’s pivotal phase 3 trial. Estimates are unadjusted. † The RSVpreF trial had two co-primary endpoints, defined as RSV LRTI with two or more lower respiratory signs or symptoms lasting >1 day, and RSV LRTI with three or more lower respiratory signs or symptoms lasting >1 day. Lower respiratory signs and symptoms included new or worsened cough, sputum production, wheezing, shortness of breath, and tachypnea. For RSVpreF estimates in this report, LRTD refers to the RSVpreF trial endpoint of RSV LRTI with three or more lower respiratory signs or symptoms. § Medically attended RSV-associated LRTD was defined as LRTD prompting any health care visit (any outpatient or inpatient visit such as hospitalization, emergency department visit, urgent care visit, home health care services, primary care physician office visit, pulmonologist office visit, specialist office visit, other visit, or telehealth contact). Estimates were not included in per-protocol assessments. ¶ Season 1 vaccine efficacy estimates reflect efficacy against first events occurring during the first complete RSV season for Northern and Southern Hemisphere participants (August 2021–October 2022; exact study-defined season dates were site-dependent). ** Season 2 (interim) vaccine efficacy estimates reflect efficacy against first events occurring during the second complete RSV season for Northern Hemisphere participants only (July 2022–January 2023; Southern Hemisphere data not yet available). †† Interim analysis underpowered to estimate efficacy. §§ Combined season 1 and 2 (interim) vaccine efficacy estimates reflect efficacy against first events occurring any time during season 1 or season 2. The mean time from start to end of efficacy surveillance was approximately 12 months per participant. Evidence regarding safety of the Pfizer vaccine consisted of data from two randomized, double-blind, placebo-controlled clinical trials, including the same ongoing phase 3 trial ( 24 ), and a phase 1/2 trial with 91 participants aged ≥65 years who received either the vaccine formulation used in phase 3 or placebo ( 25 ). Across both clinical trials, severe reactogenicity events (grade 3 or higher local or systemic reactions recorded during days 0–7 after vaccination) occurred in 1.0% of the intervention group participants, compared with 0.7% of the control group participants (pooled RR = 1.43; 95% CI = 0.85–2.39) (Table 4). The frequency of SAEs across both trials was similar in the intervention (4.3%) and control (4.1%) groups (pooled RR = 1.04; 95% CI = 0.94–1.15). A higher number of participants in the intervention group than in the control group reported atrial fibrillation as an unsolicited event within the 30 days after injection (intervention = 10 events [ 3.9” (>100 mm) from e-diary or severe grade from adverse event case report form. For fever, grade 3 corresponded to a temperature >102°F (>38.9°C) from e-diary or severe grade from adverse event case report form. For all other reactions, grade 3 corresponded to reactions that prevented normal, everyday activities. Grade 4 event corresponded only to a fever >104°F (>40°C). §§ Defined by the Advisory Committee on Immunization Practices Work Group as GBS (including GBS variants), chronic inflammatory demyelinating polyneuropathy, or acute central nervous system inflammation (e.g., transverse myelitis or acute disseminated encephalomyelitis) occurring ≤42 days after vaccination. ¶¶ Across all RSVpreF clinical trials, including trials other than the phase 3 and phase 1/2 trials summarized in this table, inflammatory neurologic events were reported in three of 20,255 adults ≤42 days after vaccination with RSVpreF (all in the phase 3 trial). The events included GBS, Miller Fisher syndrome (a GBS variant), and undifferentiated motor-sensory axonal polyneuropathy. Relative risk could not be calculated because no events were observed in the placebo-controlled comparator group. Across all Pfizer vaccine clinical trials among older adults, inflammatory neurologic events were reported in three of 20,255 participants within 42 days after receipt of the vaccine ( 15 , 26 , 27 ). The events included GBS in a participant aged 66 years from the United States with symptom onset 14 days postvaccination; Miller Fisher syndrome (a GBS variant) in a participant aged 66 years from Japan with symptom onset 10 days postvaccination; and undifferentiated motor-sensory axonal polyneuropathy with worsening of preexisting symptoms 21 days postvaccination in a participant aged 68 years from Argentina ( 15 , 26 , 27 ). Rationale for Recommendations Vaccination with a single dose of the GSK or Pfizer RSV vaccines demonstrated moderate to high efficacy in preventing symptomatic RSV-associated LRTD over two consecutive RSV seasons among adults aged ≥60 years. Although trials were underpowered to estimate efficacy against RSV-associated hospitalization and death, prevention of LRTD, including medically attended LRTD, suggests that vaccination might prevent considerable morbidity from RSV disease among adults aged ≥60 years. Although both vaccines were generally well-tolerated with an acceptable safety profile, six cases of inflammatory neurologic events (including GBS, ADEM, and others) were reported after RSV vaccination in clinical trials. Whether these events occurred due to chance, or whether RSV vaccination increases the risk for inflammatory neurologic events is currently unknown. Until additional evidence becomes available from postmarketing surveillance clarifying the existence of any potential risk, RSV vaccination in older adults should be targeted to those who are at highest risk for severe RSV disease and therefore most likely to benefit from vaccination. The recommendation for shared clinical decision-making is intended to allow flexibility for providers and patients to consider individual risk for RSV disease, while taking into account patient preferences. Recommendations for Use of RSV Vaccines in Older Adults On June 21, 2023, ACIP recommended that adults aged ≥60 years may receive a single dose of RSV vaccine, using shared clinical decision-making. §§§§ Clinical Guidance Shared Clinical Decision-Making for Adults Aged ≥60 years. Unlike routine and risk-based vaccine recommendations, recommendations based on shared clinical decision-making do not target all persons in a particular age group or an identifiable risk group. For RSV vaccination, the decision to vaccinate a patient should be based on a discussion between the health care provider and the patient, which might be guided by the patient’s risk for disease and their characteristics, values, and preferences; the provider’s clinical discretion; and the characteristics of the vaccine. As part of this discussion, providers and patients should consider the patient’s risk for severe RSV-associated disease. Epidemiologic evidence indicates that persons aged ≥60 years who are at highest risk for severe RSV disease and who might be most likely to benefit from vaccination include those with chronic medical conditions such as lung diseases, including chronic obstructive pulmonary disease and asthma; cardiovascular diseases such as congestive heart failure and coronary artery disease; moderate or severe immune compromise (either attributable to a medical condition or receipt of immunosuppressive medications or treatment) ¶¶¶¶ ; diabetes mellitus; neurologic or neuromuscular conditions; kidney disorders, liver disorders, and hematologic disorders; persons who are frail; persons of advanced age; and persons with other underlying conditions or factors that the provider determines might increase the risk for severe RSV-associated respiratory disease (Box). Adults aged ≥60 years who are residents of nursing homes and other long-term care facilities are also at risk for severe RSV disease. It should be noted that the numbers of persons enrolled in the trials who were frail, were of advanced age, and lived in long-term care facilities were limited, and persons with compromised immunity were excluded (some of whom might have an attenuated immune response to RSV vaccination). However, adults aged ≥60 years in these populations may receive vaccination using shared clinical decision-making given the potential for benefit. BOX Underlying medical conditions and other factors associated with increased risk for severe respiratory syncytial virus disease Chronic underlying medical conditions associated with increased risk • Lung disease (such as chronic obstructive pulmonary disease and asthma) • Cardiovascular diseases (such as congestive heart failure and coronary artery disease) • Moderate or severe immune compromise* • Diabetes mellitus • Neurologic or neuromuscular conditions • Kidney disorders • Liver disorders • Hematologic disorders • Other underlying conditions that a health care provider determines might increase the risk for severe respiratory disease Other factors associated with increased risk • Frailty † • Advanced age § • Residence in a nursing home or other long-term care facility • Other underlying factors that a health care provider determines might increase the risk for severe respiratory disease Abbreviation: RSV = respiratory syncytial virus. * A list of potentially immune compromising conditions is available at https://www.cdc.gov/coronavirus/2019-ncov/need-extra-precautions/people-who-are-immunocompromised.html. † Frailty is a multidimensional geriatric syndrome and reflects a state of increased vulnerability to adverse health outcomes. Although there is no consensus definition, one frequently used tool is the Fried frailty phenotype in which frailty is defined as a clinical syndrome with three or more of the following symptoms present: unintentional weight loss (10 lbs [4.5 kg] in the past year), self-reported exhaustion, weakness (grip strength), slow walking speed, and low physical activity. § Among adults aged ≥60 years, RSV incidence increases with advancing age. Although age may be considered in determining an older adult patient’s risk for severe RSV-associated disease, there is no specific age threshold at which RSV vaccination is more strongly recommended within the age group of adults aged ≥60 years. RSV Vaccination Timing RSV vaccination is currently approved and recommended for administration as a single dose; sufficient evidence does not exist at this time to determine the need for revaccination. Optimally, vaccination should occur before the onset of the RSV season; however, typical RSV seasonality was disrupted by the COVID-19 pandemic and has not returned to prepandemic patterns. For the 2023–24 season, clinicians should offer RSV vaccination to adults aged ≥60 years using shared clinical decision-making as early as vaccine supply becomes available and should continue to offer vaccination to eligible adults who remain unvaccinated. Vaccine Administration, Including Coadministration with Other Vaccines Coadministration of RSV vaccines with other adult vaccines during the same visit is acceptable.***** Available data on immunogenicity of coadministration of RSV vaccines and other vaccines are currently limited. Coadministration of RSV and seasonal influenza vaccines met noninferiority criteria for immunogenicity with the exception of the FluA/Darwin H3N2 strain when the GSK RSV vaccine was coadministered with adjuvanted quadrivalent inactivated influenza vaccine ( 28 , 29 ). RSV and influenza antibody titers were somewhat lower with coadministration; however, the clinical significance of this is unknown. Administering RSV vaccine with one or more other vaccines at the same visit might increase local or systemic reactogenicity. Data are only available for coadministration of RSV and influenza vaccines, and evidence is mixed regarding increased reactogenicity. Data are lacking on the safety of coadministration with other vaccines that might be recommended for persons in this age group, such as COVID-19 vaccines; pneumococcal vaccines; adult tetanus, diphtheria, and pertussis vaccines; and the recombinant zoster vaccine (the recombinant zoster vaccine and GSK’s RSV vaccine contains the same adjuvant). When deciding whether to coadminister other vaccines with an RSV vaccine, providers should consider whether the patient is up to date with currently recommended vaccines, the feasibility of the patient returning for additional vaccine doses, risk for acquiring vaccine-preventable disease, vaccine reactogenicity profiles, and patient preferences. Postlicensure efficacy and safety monitoring of coadministered RSV vaccines with other vaccines will further direct guidance. Precautions and Contraindications As with all vaccines, RSV vaccination should be delayed for persons experiencing moderate or severe acute illness with or without fever (precaution). RSV vaccines are contraindicated for and should not be administered to persons with a history of severe allergic reaction, such as anaphylaxis, to any component of the vaccine ( 30 , 31 ). Reporting of Vaccine Adverse Events Adverse events after vaccination should be reported to the Vaccine Adverse Event Reporting System (VAERS). Reporting is encouraged for any clinically significant adverse event even if it is uncertain whether the vaccine caused the event. Information on how to submit a report to VAERS is available at https://vaers.hhs.gov/index.html or by telephone at 1-800-822-7967. Future Research and Monitoring Priorities CDC will monitor adverse events, including cases of GBS, ADEM, and other inflammatory neurologic events after RSV vaccination through VAERS and the Vaccine Safety Datalink https://www.cdc.gov/vaccinesafety/ensuringsafety/monitoring/vsd/index.html). CDC will also prioritize estimating vaccine effectiveness against RSV-associated hospitalization. These data will be evaluated by CDC and ACIP as soon as they are available. According to FDA postmarketing requirements and commitments, GSK will conduct a study evaluating risk for GBS, ADEM, and atrial fibrillation after vaccination with RSVPreF3 ( 18 ). Pfizer will conduct two studies, one evaluating risk for GBS and a second evaluating risk for atrial fibrillation after vaccination with RSVpreF ( 19 ). Pfizer will also evaluate the safety and immunogenicity of a second RSVpreF dose in a subset of participants in the main phase 3 trial; GSK will evaluate safety, immunogenicity, and efficacy of RSVPreF3 revaccination as part of its main phase 3 trial.
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            COVID-19 Vaccination Coverage, by Race and Ethnicity — National Immunization Survey Adult COVID Module, United States, December 2020–November 2021

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              Association of provider recommendation and offer and influenza vaccination among adults aged ≥18 years – United States

              Influenza vaccination has been recommended for all persons aged ≥6 months since 2010.
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                Author and article information

                Journal
                MMWR Morb Mortal Wkly Rep
                MMWR Morb Mortal Wkly Rep
                WR
                Morbidity and Mortality Weekly Report
                Centers for Disease Control and Prevention
                0149-2195
                1545-861X
                22 December 2023
                22 December 2023
                : 72
                : 51
                : 1377-1382
                Affiliations
                Immunization Services Division, National Center for Immunization and Respiratory Diseases, CDC; Division of Readiness and Response Science, Office of Readiness and Response, CDC.
                Author notes
                Corresponding author: Carla L. Black, zwc0@ 123456cdc.gov .
                Article
                mm7251a4
                10.15585/mmwr.mm7251a4
                10754266
                38127675
                5aa62bbb-1eb5-441e-b1cc-5d6d543d79fd

                All material in the MMWR Series is in the public domain and may be used and reprinted without permission; citation as to source, however, is appreciated.

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