COVID-19 Vaccine Hesitancy and Health Literacy in US Southern States

ABSTRACT

Objectives: COVID-19 vaccination in the United States has stalled, with some of the lowest rates in the South. Vaccine hesitancy is a primary contributor and may be influenced by health literacy (HL). This study assessed the association between HL and COVID-19 vaccine hesitancy in a population residing in 14 Southern states.

Study Design: Cross-sectional study using a web-based survey conducted between February and June 2021.

Methods: The outcome was vaccine hesitancy, and the main independent variable was HL, assessed as an index score. Descriptive statistical tests were performed, and multivariable logistic regression analysis was conducted, controlling for sociodemographic and other variables.

Results: Of the total analytic sample (n = 221), the overall rate of vaccine hesitancy was 23.5%. Vaccine hesitancy was more prevalent in those with low/moderate HL (33.3%) vs those with high HL (22.7%). The association between HL and vaccine hesitancy, however, was not significant. Personal perception of COVID-19 threat was significantly associated with lower odds of vaccine hesitancy compared with those without perception of threat (adjusted odds ratio, 0.15; 95% CI, 0.03-0.73; P = .0189). The association between race/ethnicity and vaccine hesitancy was not statistically significant (P = .1571).

Conclusions: HL was not a significant indicator of vaccine hesitancy in the study population, suggesting that general low rates of vaccination in the Southern region may not be due to knowledge about COVID-19. This indicates a critical need for place-based or contextual research on why vaccine hesitancy in the region transcends most sociodemographic differences.

Am J Manag Care. 2023;29(6):300-306. https://doi.org/10.37765/ajmc.2023.89371

Takeaway Points

Using a cross-sectional web-based survey, we assessed the association between health literacy and COVID-19 vaccine hesitancy in a US Southern population. We report that personal perception of threat was associated with reduced vaccine hesitancy. The following are the highlights of our study:

• Vaccine hesitancy in Southern states is complex and extends beyond health literacy.
• Vaccine hesitancy in Southern states transcends many sociodemographic differences.
• Effective public health communication should be unambiguous about negative externalities of COVID-19 beyond individual threats.

The COVID-19 pandemic caused by SARS-CoV-2 remains a public health crisis, accounting for more than 100 million confirmed cases with more than 1,121,800 deaths in the United States as of April 26, 2023.¹ Despite widespread vaccination efforts by the US government and public health leadership, the rate of vaccine uptake is still far from desirable, as researchers estimate that about 70% to 85% of the country will need to be immunized before SARS-CoV-2 can be fully contained through herd immunity.² As of April 19, 2023, about 81% of the US population had received at least 1 dose, whereas 69.4% had completed a full primary vaccine series and only 16.7% had received an updated bivalent booster, with variations in the rate of vaccination across states and regions.³ The Southern states (Alabama, Arkansas, Florida, Georgia, Kentucky, Louisiana, Maryland, Mississippi, North Carolina, South Carolina, Tennessee, Texas, Virginia, and West Virginia) have relatively lower rates of full vaccination (primary series) compared with other states (mean of 61.3%, ranging from 53.2% in Alabama to 79.9% in Maryland); 6 Southern states rank among the 10 states with the lowest fully vaccinated rates in the nation.³

The predominant barrier to uptake has been vaccine hesitancy,^4-9 defined as the intention to delay or refuse taking vaccinations despite availability and accessibility.^10,11 It may be influenced by complex contextual factors, ranging from individual and group factors to vaccine-specific characteristics.¹⁰ In particular, individual factors may be related to health literacy (HL),¹² which is the degree to which individuals have the ability to find, understand, and use information and services to inform health-related decisions and actions for themselves and others.¹³ HL is a phenomenon that involves individuals, families, communities, and systems, and it could be implicated in the level of COVID-19 vaccine hesitancy.⁵

Although HL is a major determinant of individuals’ health behaviors,¹⁴ a systematic review study reported that HL’s relationship with vaccination uptake prior to the COVID-19 pandemic was unclear because of variations in assessment tools, target populations, and outcome measures across available limited studies.¹⁵ Evidence suggests a relationship between HL and COVID-19 vaccine hesitancy.^12,16,17 In the United States, a study among women recently released from jails found that low HL is related to COVID-19 vaccine hesitancy.¹⁶ Similarly, a study in Turkey found that low HL and a high perception of health care system distrust are associated with higher vaccine hesitancy.¹⁷ A study in China found that higher HL is associated with low likelihood of COVID-19 vaccine hesitancy, and the effect was moderated by stress.¹² Overall, to the best of our knowledge, no study has examined the association between HL and COVID-19 vaccine hesitancy in populations with low vaccine uptake within the United States, including those residing in the Southern states, which served as the impetus for this study.^18,19

This study aimed to estimate the level of HL among a population residing in Southern states and its association with vaccine hesitancy. It is hypothesized that HL would reduce the likelihood of vaccine hesitancy. Nearly 20% of the United States population had still not received a single dose of COVID-19 vaccine as of April 26, 2023, despite increases in both vaccine availability and individual eligibility over the previous 2 years.²⁰ The observed trends in overall and region-specific COVID-19 cases and rates of vaccination in the United States demonstrate the need to examine the impact of HL on vaccine hesitancy in the Southern states, especially with the release of simplified eligibility guidelines and expanded booster recommendations.²¹

METHODS

Participants

This study included adults 18 years and older. Upon receiving institutional review board (IRB) approval from East Tennessee State University (IRB No. c0221.22e), a cross-sectional study was initiated. Between February and June 2021, an online REDCap survey was administered to the target population through the snowball approach, the research website of the Center for Cardiovascular Risk Research at East Tennessee State University, social media (eg, Facebook), email, conferences, and individual networks. The purpose of this online REDCap survey was to understand and identify the barriers to and facilitators of adherence to COVID-19 mitigation measures, testing, and vaccine uptake and hesitancy in this population at high risk for COVID-19–induced hospitalization and fatalities. A total of 417 individuals participated in this online REDCap survey. Only participants in Southern states who reported that they were patients or community members were included in the final analytic sample, leaving 221 participants; 92.2% were non-Hispanic White, and 7.8% of participants self-identified as a racial/ethnic minority.²²

Measures

The questionnaire utilized for this study entailed adapted standardized and validated questions for studying vaccine hesitancy, confidence, acceptance, and uptake from the Census Bureau,²³ CDC,²⁴ and Health Resources and Services Administration.²⁵ Thus, the following are the pertinent questions utilized for this study.

Dependent variable. The main outcome was vaccine hesitancy, assessed by the question: “When the vaccine for COVID-19 becomes available to you, will you seek to obtain it?” Responses included: (1) I have already received the vaccine, (2) I will contact my health care provider to get the vaccine, (3) I will wait and see how others in the community respond before getting it myself, (4) I do not think I will get the vaccine but I want to learn more before deciding, (5) I will obtain more information about the vaccine, and (6) I do not plan to obtain this vaccine. These responses were recoded as a dichotomous variable, with options 1 and 2 as “vaccinated or intentions to vaccinate” and options 3 through 6 as “hesitancy to vaccinate.”

Independent variable. The main independent variable was HL, which was assessed using a validated measure.²⁶ This measure asked 3 questions and an aggregate of responses was used to form an HL index.²⁷ This resulted in composite scores ranging from 6 to 15. We then recoded HL index as a categorical variable with composite scores of 6 to 12 as low or moderate HL and 13 to 15 as high HL. Of note, low and moderate HL were combined because of small sample sizes.

Covariates

Covariates included demographic characteristics, COVID-19 perceptions, medical or health conditions, sources of COVID-19–related information, and adherence to COVID-19 mitigation measures. Demographics were age, sex, race/ethnicity, and highest level of education. Age was categorized as 18 to 30 years, 31 to 59 years, and 60 years or older. Sex was dichotomous (female and male). Race/ethnicity was collected as: (1) Asian or Pacific Islander, (2) Black or African American, (3) Hispanic/Latino, (4) Native American or Alaskan Native, (5) non-Hispanic White, (6) biracial or multicultural, and (7) race/ethnicity not listed here. Because of small sample sizes for non-White racial/ethnic groups in the study population, race/ethnicity was recoded as non-Hispanic White and other. Highest level of education was recoded as high school/General Educational Development, some college/associate degree/bachelor’s degree, and postgraduate degree.

COVID-19 perceptions were assessed with 3 questions: (1) “Do you believe that COVID-19 is a significant public health risk to you (yes or no)?” which was termed “personal perception of COVID-19 threat”; (2) “What level of risk do you believe COVID-19 presents to you (none, low, moderate, or high)?” which was termed “personal perception of level of risk”; and (3) “In light of information regarding COVID-19 that has been reported by national and local news media outlets, do you believe the severity of this disease is reported accurately/factually, underestimated/more serious, or overstated/not as serious?” which was termed “perception of accurate/factual information about COVID-19 from media sources.”

Medical or health conditions assessed were high blood pressure, high cholesterol, diabetes, heart diseases, stroke, cancer, chronic obstructive pulmonary disease, autoimmune disorders (eg, rheumatoid arthritis, lupus), and nervous system disorders (eg, epilepsy, multiple sclerosis, Parkinson disease).

The sources from which participants obtained COVID-19–related information were obtained by asking: “Where do you receive public health information and updates about COVID-19?” Response options were (check all that apply): (1) current White House administration; (2) state website; (3) CDC website; (4) state or county health department; (5) primary care provider or specialist; (6) national news outlets (eg, CBS, ABC, NBC, FOX, CNN); (7) local TV media outlets; (8) employer; (9) social media (eg, Facebook, Twitter, Instagram, Reddit, Parler); (10) podcasts, blogs, or media influencers; (11) streaming services (eg, YouTube, Hulu, Netflix, Pluto, SlingTV); (12) friends/family; (13) church or religious organization; (14) club or social organization; and (15) others. Responses were collapsed and recoded as “government sources,” “public health sources,” “health care provider,” “news media,” “employer,” “social media,” “family or friends,” and “social organizations.”

Adherence to COVID-19 mitigation strategies was assessed using a previously published measure.²⁸ Responses were aggregated to create adherence scores ranging from 6 to 15. Scores ranging from 6 to 12 indicate low/moderate adherence, whereas scores of 13 to 15 denote high adherence.

Statistical Analysis

Descriptive analysis and bivariate associations were conducted with the main independent (HL) and dependent (vaccine hesitancy) variables along with other covariates using χ² tests. Multivariable logistic regression was performed to examine associations between HL and vaccine hesitancy while controlling for age, sex, race/ethnicity, all variables emphasizing COVID-19 perceptions, medical or health conditions, and all sources from which participants obtained COVID-19 information. The level of statistical significance was set as a P value less than or equal to .05. SAS version 9.4 (SAS Institute) was used to conduct all statistical analyses.

RESULTS

Descriptive and Bivariate Associations

Table 1 [part A and part B] shows the population characteristics and results of the bivariate analysis. Overall, 23.5% of study participants (n = 221) were identified to be vaccine hesitant. Vaccine hesitancy was more prevalent in those with low/moderate HL (33.3%) vs those with high HL (22.7%). The prevalence of vaccine hesitancy was highest among the group aged 18 to 30 years (30.0%) compared with those aged 31 to 59 years (24.2%) and those 60 years and older (17.5%). Women (25.3%) reported a higher prevalence of vaccine hesitancy than men (13.9%). Pertaining to race or ethnicity, 22.2% of non-Hispanic White respondents were vaccine hesitant compared with 38.9% of respondents of all other races/ethnicities. Rates of vaccine hesitancy were 56.8% in those who had no personal perception of COVID-19 threat, 38.9% in those who had no/low personal perception of level of risk, and 57.4% in those who reported that their perception of severity after exposure to national and local news was overstated or not as serious as reported. Approximately 64.7% of participants reported no medical conditions. Sources from which respondents obtained information included government sources (12.5% were vaccine hesitant), public health sources (17.4%), health care provider (20.6%), news media (20.3%), employer (22.7%), social media (23.1%), family or friends (32.8%), and social organizations (42.9%). Among individuals with low/moderate adherence scores, 75% were vaccine hesitant, whereas 19.4% of individuals with high adherence scores were vaccine hesitant.

Multivariable Associations

Table 2 presents the multivariable logistic regression of the association between independent variables and vaccine hesitancy. After adding covariates to our model, including age, sex, race/ethnicity, personal perception of COVID-19 threats, perception of severity after exposure to national and local news, medical or health conditions, all sources of information, and adherence, the adjusted odds ratio (AOR) for the association between low/moderate HL vs high HL and vaccine hesitancy was 0.61 (95% CI, 0.10-3.71; P = .5958). Individuals who reported having a personal perception of COVID-19 threat had lower odds of reporting vaccine hesitancy than those without a personal perception of COVID-19 threat (AOR, 0.15; 95% CI, 0.03-0.73; P = .0189).

DISCUSSION

After the initial accelerated uptake of COVID-19 vaccine, progress has stalled such that as of April 26, 2023, only about 70% of the overall US population was completely vaccinated, with states in the Southern region of the country having some of the lowest rates of vaccination compared with other regions (Figure³). A key reason for the stalled progress in the vaccination rate in the United States is vaccine hesitancy.^4-6 Research suggests that there are several underlying factors for vaccine hesitancy, and HL has been identified as one of them.^26,29,30 It was found within this study involving a population residing in Southern states that 1 in 4 was vaccine hesitant. The results of the multivariate regression model, however, show that HL was not significantly associated with vaccine hesitancy in this population, which contradicts findings of previous studies involving other vaccines,^17,29-31 but is consistent with a systematic review that found that the relationship between vaccine hesitancy and HL is unclear.¹⁵ One explanation could be that a high proportion of the total participants were categorized as having high HL (92.1%), hence diminishing the ability to detect a significant difference in this outcome. Despite this, it is concerning that approximately 1 in 4 of all the participants who self-identified as having high HL was still hesitant to receive the COVID-19 vaccine. Coupling this result with the nonsignificant finding for the level of education and vaccine hesitancy in this study, HL may not be the primary source of COVID-19 vaccine hesitancy. The results of this study could direct future researchers to focus on other potential causes of vaccine hesitancy among residents in these Southern states, including the potential for misinformation, and distrust of the health care system, and other sociopolitical factors.¹⁷

Among the participants in this study, those who perceived COVID-19 as a personal threat were significantly less likely to be vaccine hesitant than their counterparts. Perceptions about a public health issue are a major predictor of health behaviors.³² Indeed, the health belief model of health promotion suggests that perceptions of risk and severity are key determinants of health behaviors.³² Specific to COVID-19, a recent study by Ahuja et al involving patients with chronic diseases and other interested persons from the Appalachian region of the southern United States found that perceptions of risks from COVID-19 were significantly associated with vaccine uptake and adherence to COVID-19 mitigation measures.²⁸ Consistent with these prior studies, the findings of this study indicate that personal perception of threat of COVID-19 significantly decreased the probability of vaccine hesitancy. These results suggest that future initiatives should target perceptions of personal health effects of COVID-19 in these Southern states. The homogeneity of the sample may account for the differences in personal perception of threat of COVID-19 compared with findings from a national study in which personal threat was higher in minority groups.³³ The relatively small sample for this study is likely a barrier for other studies evaluating similar outcomes in this population; therefore, different types of research including both qualitative and quantitative approaches are needed to disentangle this complex association between perceived personal threat of COVID-19 and vaccine hesitancy.

This study has some implications for public health approaches to COVID-19 vaccination. It is clear from the relatively highly educated population in this study that COVID-19 vaccine hesitancy is not about knowledge and awareness of the efficacy, effectiveness, and safety of the vaccines—a contradiction to the literature on general vaccination^34-38 but consistent with the ambiguity about COVID-19.^15,39 This means that the one-size-fits-all approach should be revisited. Contextual and place-based factors such as culture, history, and political ideology may be more important to people living in a social and community setting than their risk of getting COVID-19. In addressing context, it is important to identify and address available local resources such as local news outlets, along with community leaders. Therefore, having local leaders on board to provide the same message as government officials is a strategy that must be addressed. However, more research is critically needed to unpack why vaccine hesitancy in Southern states, including in the Appalachian region, transcends sociodemographic differences.

Limitations

Limitations include a relatively homogenous, non-Hispanic White study population; therefore, the findings may not be generalized to include other racial/ethnic groups because a previous study has reported higher perceived personal threat of COVID-19 in minority groups.³³ Second, study participants had a high level of education, which was possibly not representative of the region’s population, so that could mean that vaccine hesitancy is underestimated while constraining the ability to generalize the results. Nonetheless, the fact that 1 in 4 of this highly educated population was vaccine hesitant indicates the pervasiveness of the problem in these Southern states and that HL may be a lesser factor than anticipated. Third, this was a cross-sectional study; therefore, the results cannot establish causation. Fourth, this is a self-reported online survey and, as such, it is subject to biases such as recall, social desirability, and selection. However, this was an anonymous survey, which suggests that the results reflect the true perspective of individuals residing in the region. Lastly, the sample size is relatively small. Nevertheless, this is perhaps the first study involving COVID-19 vaccine hesitancy and HL in a population residing in Southern states and still informs the ongoing initiatives to bolster vaccination rates in the Southern states and nationwide through initiatives and research.

CONCLUSIONS

Vaccine hesitancy is a major contributor to stalled vaccination rates seen in the United States, and HL has been implicated as a contributing factor. However, the results of this study demonstrate that among residents in Southern states, HL was not significantly associated with COVID-19 vaccine hesitancy. These findings suggest that vaccine hesitancy in Southern states may be more than an issue of HL and that public health communication should unambiguously communicate the negative externalities of COVID-19 beyond the individual. Ultimately, studies that provide contextual insights are critically needed to inform targeted policies/programs to address the stalled COVID-19 vaccination rates.

Acknowledgments

The study instrument and this manuscript were reviewed by colleagues and students not part of the authorship, and the authors would like to thank them for their time and input. Above all, the authors would like to thank all the participants who completed the survey for the willingness to advance the science on COVID-19.

Author Affiliations: College of Public Health (HMM, MA, EA, AO, JC), College of Nursing (BH, FMW), College of Pharmacy (KD-M, DWS), College of Arts and Sciences (RAF), and Information Technology Services (JK), East Tennessee State University, Johnson City, TN; University of Tennessee College of Medicine at Nashville, Ascension Saint Thomas Hospital (TKP), Nashville, TN.

Source of Funding: None.

Author Disclosures: The authors report no relationship or financial interest with any entity that would pose a conflict of interest with the subject matter of this article.

Authorship Information: Concept and design (HMM, EA, AO, KD-M, DWS, JC, TKP, FMW); acquisition of data (HMM, KD-M, JC, JK, FMW); analysis and interpretation of data (HMM, MA, EA, BH, KD-M, RAF, DWS, TKP, FMW); drafting of the manuscript (HMM, MA, EA, AO, BH, RAF, JC, FMW); critical revision of the manuscript for important intellectual content (HMM, MA, EA, AO, BH, KD-M, RAF, DWS, JC, TKP, FMW); statistical analysis (EA); provision of patients or study materials (JC); administrative, technical, or logistic support (EA, JK); instrument development/maintenance and data security (JK); and supervision (HMM, DWS).

Address Correspondence to: Hadii M. Mamudu, PhD, MPA, College of Public Health, East Tennessee State University, Lamb Hall, Room 159, Box 70264, Johnson City, TN 37614. Email: mamudu@etsu.edu.

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