State Variation in Seasonal Flu Vaccination: Implications for a COVID-19 Vaccine
Introduction
Once a COVID-19 vaccine has been authorized or approved by the Food and Drug Administration (FDA), states will play a central role in its distribution. While the Centers for Disease Control and Prevention (CDC) recently released guidance to state and local jurisdictions for preparing for a COVID-19 vaccine, state level engagement and success around vaccine distribution is likely to differ. Yet, to achieve sufficient levels of immunity against COVID-19, most, if not all, people in the United States will need to be vaccinated, and variation in COVID-19 vaccination rates across the country could significantly impede efforts to control the pandemic. As states consider the logistics of what will likely be an unprecedented vaccination campaign, analysis of routine vaccination rates by state may help to shed light on differential uptake across the country as well as inform where more targeted efforts might be needed. Specifically, we analyzed seasonal flu vaccination rates for the 2019-2020 flu season by state, as well as across states by age, race/ethnicity, and health risk status. Data were obtained from the CDC’s 2019-20 Influenza Season Vaccination Coverage Dashboard and are also available at KFF’s State Health Facts.
Routine annual flu vaccination has been recommended by the CDC’s Advisory Committee on Immunization Practices (ACIP) for anyone ages 6 months and older for the past decade and, because of the Affordable Care Act (ACA), is available free of charge to those with insurance, to uninsured children, through the Vaccines for Children Program, and to some uninsured adults (although to a much lesser extent). Still, national rates are well below the Healthy People 2030 target of 70% and vary by race/ethnicity and age. Looking across the states, we also find significant variation overall, and by race/ethnicity, age, and health status. In some cases, there are higher flu vaccination rates among groups that are likely to be prioritized for a COVID-19 vaccine, such as older Americans; in others, however, many states have low vaccination rates among those who have already been disproportionately impacted by COVID-19 and will be critical to reach with a vaccine, such as people of color, particularly Black Americans, who have expressed significant reluctance about getting a COVID-19 vaccine. While there are important differences between COVID-19 and seasonal flu, including that COVID-19 is much more serious and that the federal government has said it will ensure the vaccine is provided free to all even those who are uninsured, these findings point to several potential challenges to rolling out a COVID-19 vaccine across the United States.
Overall State Variation
During the 2019-2020 flu season, flu vaccination rates varied significantly by state, and all states fell below national targets. Across the U.S., 52% of the U.S. population (6 months and older) received the seasonal flu vaccine last season. Rates ranged from a low of 44% in Nevada to a high of 61% in Rhode Island. In 12 states, less than half of the population was vaccinated for the flu. In addition, all 50 states and DC fell short of the U.S.’s Healthy People 2030 goal of having at least 70% of the population receive the seasonal flu vaccine (Figure 1). There was also variation by region. Rates were highest in the Northeast (57%), followed by the Midwest (54%), the South (52%) and lastly, the West (51%) (Figure 2).
Race/Ethnicity
Achieving a high COVID-19 vaccination rate among people of color will be particularly important because they are bearing a heavy, disproportionate burden of the disease, and population immunity is not likely to be reached without high vaccination rates across all communities. Earlier KFF analysis of flu vaccination rates at the national level showed persistent gaps and racial disparities among adults, with lower rates of vaccination among Black, Hispanic, and American Indian and Alaska Native adults compared to their White counterparts. A separate analysis reported similar findings for older (65+) Black and Hispanic adults compared to White adults.
Our analysis of flu vaccination rates by state and race/ethnicity provides additional insight into such variation. Specifically, we looked at rates for all individuals ages six months or older by race/ethnicity among White, Black, and Hispanic people. Data could not be further disaggregated by race/ethnicity and age and some states could not be included due to unreliable data (Appendix 1).1
Across racial and ethnic groups, flu vaccination rates remained below the target level in nearly all states. Only DC achieved vaccination rates above the 70% target for White people (71%); however, its rate for Black people fell well below the target at 44%. No state achieved the target vaccination level for Black or Hispanic people.
The range in vaccination rates by state was similar across racial and ethnic groups, but the overall rates for Black and Hispanic people were below that of White people. Specifically, flu vaccination rates ranged from 30% in Nevada to 60% in Nebraska for Black people and from 37% in Florida to 62% in New Hampshire for Hispanic people. For White people, the rate ranged from 45% in Idaho to 71% in DC (Figure 3).
In most states, Black and Hispanic people had lower flu vaccination rates compared to their White counterparts, but these differences varied across states. Consistent with earlier analysis showing lower rates of flu vaccination among adults, we find that Black and Hispanic people were less likely to have received the flu vaccination compared to their White counterparts (46% and 47% compared to 55%). However, these differences varied across states (Figure 4).
Black people had a lower flu vaccination rate compared to White people in 36 states, with the largest gaps in DC (44% vs. 71%), Nevada (30% vs. 47%), Maryland (49% vs. 64%), and New Jersey (45% vs. 59%). In only one state did Black people have higher vaccination rates compared to White people (Oklahoma, 58% compared to 54%).1
Hispanic people had a lower flu vaccination rate compared to White people in 40 states. The largest gaps were in Florida (37% vs. 50%), Connecticut (54% vs. 64%), and Michigan (41% vs. 52%). Hispanic people had a higher vaccination rate compared to White people in 7 states. (Alaska, Arkansas, Louisiana, Mississippi, Montana, New Hampshire, and Wyoming).1
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Age
In most states, flu vaccination rates were highest for seniors, followed by children, and lowest for non-elderly adults 2 (Appendix 2). As states develop COVID-19 vaccination plans, age will likely be a key factor in determining priority groups, due to the increased risk COVID-19 poses for older adults. Across states, the vaccination rate among seniors age 65 and older was 70%, ranging from 54% in Alaska to 79% in North Carolina. A total 30 states met or exceeded the 70% Healthy People 2030 goal (Figure 5).
Coverage for children, ages 6 months to 17, ranged from 52% in Mississippi to 78% in Rhode Island; 10 states and DC met or exceeded the national target rate of 70% among children. Rates were lowest among non-elderly adults, ages 18-64, ranging from 33% in Florida to 52% in Rhode Island. No state reached the 70% target for this population (Figure 6).
Health-Risk Status
Adults with comorbidities were more likely to be vaccinated for the flu, compared to those without such conditions, but rates were still well below national targets in all states. Similarly to older adults, individuals under 65 with certain underlying medical conditions are at a heightened risk of severe illness from COVID-19. As such, they are likely to be a priority group for a COVID-19 vaccine roll out. Overall, in the 2019-2020 season, non-elderly adults with certain underlying health conditions 3 were more likely to receive the seasonal flu vaccine (51%) compared to those without (40%), though still below the Healthy People 2030 target in all states (Appendix 3). Rates among adults with comorbidities varied significantly by state ranging from 38% in Florida to 61% in Connecticut and Vermont. For adults without underlying health conditions, flu vaccination rates were much lower, ranging from 31% in Nevada to 50% in Rhode Island (Figures 7 and 8)..
Discussion
Overall, we observed low rates of flu vaccination uptake across the country last season, well below national goals, and substantial variation by state and between groups. Rates were highest in the Northeast and lowest in the West. In most states, rates were highest among seniors, followed by children, and lowest among non-elderly adults. Rates were also highest in most states among White people compared to Black and Hispanic people and the lowest state rates for Black and Hispanic people were below that of White people. Rates were also higher among adults with co-morbidities, compared to those without.
There are several potential factors that may affect flu vaccination rates across states, including: lower rates of insurance coverage for some groups, particularly people of color; the lack of dedicated vaccination programs for uninsured and underinsured adults, compared to children; differential access to health care; the relatively small number of states that mandate flu vaccine; differences in funding and vaccine infrastructure by state; and variation in levels of concern or misconceptions about vaccine safety, side effects, and efficacy. While there are important distinctions between COVID-19 and seasonal flu, including that COVID-19 is much more serious, and the public’s receptivity to a COVID-19 vaccine may differ from that of the flu vaccine, these findings suggest there may be significant challenges to achieving equity in distribution and sufficient levels of immunity in the U.S. with a COVID-19 vaccine.
As states and other stakeholders plan for distribution of a COVID-19 vaccine, targeting those states that already have disproportionately lower coverage rates for routine vaccination, particularly for populations most affected by COVID-19 and who appear to face greater barriers to vaccination, may provide an important avenue for increasing success. It will be important for vaccination efforts to address a range of barriers, including potential barriers to access and cost concerns, particularly among those who are uninsured. It also will be important to address concerns about safety and potential side effects of the vaccine, particularly among Black Americans. The recently released KFF/The Undefeated Survey found that just 17% of Black Americans say they would definitely get a COVID-19 vaccine if it was determined safe and available for free, compared to 37% of White Americans, largely due to safety concerns or distrust of the health care system.