Adult Vaccination Status in the Elderly Population: A Cross-Sectional Evaluation

doi:10.21203/rs.3.rs-8500923/v1

Background

Vaccination is a cornerstone of preventive medicine; however, adult vaccination coverage remains suboptimal, particularly among older populations. Age-related immunosenescence, the high burden of chronic diseases, and increased susceptibility to severe infections underscore the importance of adult immunization in individuals aged 65 years and older.

Aims

This study aimed to evaluate adult vaccination status among individuals aged ≥65 years, identify factors influencing vaccination decisions, and assess the impact of the COVID-19 pandemic on vaccination behaviors.

Methods

This single-center, descriptive study was conducted in the vaccination outpatient clinics of a tertiary training and research hospital. A total of 1,800 individuals aged ≥65 years were included. Data were collected through face-to-face questionnaires covering sociodemographic characteristics, chronic diseases, adult vaccination status, reasons for vaccination, and pandemic-related changes in attitudes. Vaccines routinely recommended for older adults—seasonal influenza, pneumococcal conjugate vaccine (PCV), COVID-19, tetanus–diphtheria (Td), and herpes zoster—were evaluated. Categorical variables were analyzed using chi-square tests.

Results

The highest vaccination rates were observed for PCV (46.7%) and seasonal influenza (33.2%), while herpes zoster vaccination was extremely low (0.6%). Vaccination rates were significantly higher among individuals with higher educational levels, chronic diseases, and those who believed in vaccine effectiveness (p<0.05). The COVID-19 pandemic significantly increased acceptance of influenza and pneumococcal vaccines, with post-pandemic pneumococcal vaccination rates nearly doubling compared with the pre-pandemic period.

Discussion

Findings indicate persistent gaps in adult immunization coverage, despite improved awareness during the pandemic, particularly for vaccines other than influenza and pneumococcal vaccines.

Conclusions

Adult vaccination rates among older individuals remain below target levels. Strengthening health literacy, reinforcing physician recommendations, and sustaining pandemic-related awareness may improve adult immunization, especially for underutilized vaccines such as herpes zoster.

Adult immunization

influenza

pneumococcal vaccine

herpes zoster vaccine

older adults

pandemic

Vaccination is one of the most effective methods for preventing infectious diseases, and the effectiveness of childhood immunization has been proven worldwide [1,2]. However, the importance of immunization is not limited to childhood alone. Demographic changes, the increasing elderly population, and the higher frequency and severity of infections in this age group make adult vaccination increasingly critical [1]. The aging process increases susceptibility to infections through a physiological decline in the immune system known as immunosenescence. Factors such as chronic comorbidities, the use of immunosuppressive medications, crowded living conditions, weakening of cellular and humoral immunity, a decreased cough reflex, and delayed wound healing further exacerbate this vulnerability [3]. Therefore, in older age groups, not only chronic diseases but also infections such as influenza and pneumonia are among the leading causes of morbidity and mortality [4,5]. In particular, exacerbations of chronic lung diseases and secondary bacterial coinfections increase hospitalization rates and the risk of death in this population [5]. In addition, influenza infection increases the risk of cardiovascular events, and seasonal influenza vaccination has been reported to indirectly reduce this risk, especially in older individuals with cardiovascular comorbidities [6,7].

Despite this, adult vaccination rates remain low. According to data from Australia and Switzerland, more than half of individuals in risk groups had not received the seasonal influenza vaccine, and more than two-thirds had not been vaccinated against pneumococcal disease [4]. In the United States, adult vaccination rates have also been reported to lag behind national targets [8,9]. In our country, it is likewise known that adequate vaccination coverage has not yet been achieved. Understanding the barriers to vaccination is essential to increasing immunization rates among older adults.

The aim of this study is to evaluate adult vaccination status among individuals aged 65 years and older, the factors influencing vaccination decisions, and the impact of the pandemic period on this behavior.

Study Aim and Design

This study was designed as a single-center, descriptive study and was conducted in the Vaccination Outpatient Clinics affiliated with the Family Medicine Clinic of SBÜ Şişli Hamidiye Etfal Training and Research Hospital. Individuals aged 65 years and older who applied to the vaccination outpatient clinic, agreed to participate in the study, and had no hearing or visual impairments that could hinder communication were included. In total, 1,800 individuals aged 65 years and older were enrolled in the study.

In the power analysis performed using a medium effect size (w = 0.30), a significance level of 5% (α = 0.05), and a statistical power of 95% (1–β = 0.95), the minimum required sample size was calculated to be between 400 and 450 individuals. The inclusion of a total of 1,800 individuals aged 65 years and older in this study resulted in a sample size approximately four times greater than the estimated minimum requirement, and the study was therefore conducted with high statistical power, exceeding 99%. Accordingly, the sample size of the study was considered sufficient to detect effects with high reliability and accuracy.

Data Collection Tool and Method

The questionnaire, prepared by the researchers in line with the literature, was administered using a face-to-face interview method. The survey included questions on participants’ sociodemographic characteristics, existing chronic diseases, adult vaccination status, reasons for receiving influenza and pneumococcal vaccines, and the impact of the pandemic process on attitudes and behaviors toward vaccination.

As the target population of the study consisted of individuals aged 65 years and older, vaccines that are routinely recommended for this age group without prior testing—seasonal influenza, pneumococcal conjugate vaccine (PCV), COVID-19, tetanus–diphtheria (Td), and herpes zoster vaccines—were evaluated in greater detail. For these vaccines, vaccination status, reasons for receiving or not receiving the vaccines, and the impact of the pandemic period on decision-making processes were examined in detail. Other vaccines were not elaborated on; only overall vaccination status was recorded in percentage terms.

Statistical Analysis

Data were analyzed using the SPSS version 25.0 software. Categorical variables were summarized as numbers and percentages. Pearson’s chi-square test was used for comparisons between groups, and Fisher’s exact chi-square test was applied when appropriate. A p-value of <0.05 was considered statistically significant. The sample size analysis for the study was performed based on the chi-square test.

Ethical Approval

Ethical approval for this study was obtained from the Clinical Research Ethics Committee of the Health Practice and Research Center of SBÜ Şişli Hamidiye Etfal Training and Research Hospital (approval date: 02/03/2021; approval number: 1830).

The mean age of the participants was 70.05 ± 4.63 years; 53.4% (n=962) were female and 46.6% (n=838) were male. Regarding marital status, 70.9% (n=1,277) were married and 29.1% (n=523) were single. In terms of educational level, 22.1% (n=397) were illiterate, 52.7% (n=948) had an education below high school level, and 25.3% (n=455) had a high school education or higher. Among the participants, 17.9% (n=311) were smokers, and 18.4% (n=331) lived alone. The prevalence of chronic disease was 62.4% (n=1,123); reported conditions included pulmonary disease in 12.2% (n=220), diabetes in 25.7% (n=463), cardiovascular disease in 41.1% (n=739), and malignancy in 2.3% (n=41).

When adult vaccination status was examined, the highest vaccination rates were observed for PCV (46.7%; n=841) and the seasonal influenza vaccine (33.2%; n=597), followed by the tetanus–diphtheria (Td) vaccine (16.1%; n=289), while the lowest rate was found for the herpes zoster vaccine (0.6%; n=10) (Figure 1). All participants had received at least one dose of the COVID-19 vaccine.

Td vaccination rates were significantly higher among individuals who had received the seasonal influenza vaccine. Similarly, Td vaccination rates were significantly higher among those who had received PCV (p<0.001). Educational level was found to have a significant effect on vaccination status. Individuals with a high school education or higher had significantly higher rates of Td, seasonal influenza, and pneumococcal vaccination (p<0.05). In contrast, no significant association was found between educational level and herpes zoster vaccination (p>0.05). The presence of chronic disease was significantly associated with seasonal influenza and pneumococcal vaccination; likewise, the presence of pulmonary disease, diabetes mellitus, and cardiovascular disease showed significant associations with seasonal influenza and pneumococcal (pneumonia) vaccination (p<0.05). No significant differences were observed for other vaccines (p>0.05).

Among the participants, 54.9% (n=989) reported believing that the COVID-19 vaccine was protective. Of those vaccinated against COVID-19, 34.1% (n=614) stated that they were vaccinated because they were over 65 years of age; 11.2% (n=201) because of chronic disease; 2.0% (n=36) because they were not concerned about side effects; and 3.1% (n=56) for other reasons.

Among those who received the seasonal influenza vaccine, 46.7% (n=279) stated that they believed the vaccine was protective; 34.0% (n=203) reported being vaccinated because they were over 65 years of age; 16.4% (n=98) due to chronic diseases; 36.7% (n=219) reported receiving the vaccine for the first time as a result of the pandemic; and 7.9% (n=47) indicated other reasons for influenza vaccination.

Among those who received the pneumococcal vaccine, 57.3% (n=482) reported believing that the vaccine was protective; 30.8% (n=259) stated that they were vaccinated because they were over 65 years of age; 13.2% (n=111) due to chronic diseases; 15.2% (n=128) to avoid illness during the pandemic period; and 5.0% (n=42) for other reasons.

The highest proportion of participants (37.9%; n=682) reported that they began to believe in vaccines after the pandemic, while 34.0% (n=612) stated that they continued to receive all recommended vaccines as they had before the pandemic. The proportion of participants whose views on vaccination did not change and who still did not intend to receive other vaccines was 28.1% (n=506).

According to Table 1, participants’ reasons for vaccination were significantly associated with receiving both the seasonal influenza and PCV vaccines (p<0.001 for all comparisons). Among those who believed in the protective effect of vaccines, the vast majority had received the seasonal influenza vaccine, with a vaccination rate of 95.5% (n=279). All individuals in this group (n=482) had received the PCV. Similarly, vaccination rates were high among those who considered themselves at risk due to age; in this group, 93.5% (n=203) had received the influenza vaccine and 100% (n=259) had received the PCV vaccine. Among those who reported being vaccinated due to chronic disease risk, the seasonal influenza vaccination rate was 99.0% (n=98) and the PCV vaccination rate was 100% (n=111). These findings indicate that belief in the protective effect of vaccines, advanced age, and the presence of chronic disease are key motivating factors that significantly increase both influenza and pneumococcal vaccination uptake.

A significant association was observed between receiving the seasonal influenza vaccine and changes in vaccination attitudes during the pandemic; the seasonal influenza vaccination rate was 32.6% (n=222) among those whose views changed due to the pandemic, 27.5% (n=139) among those whose views did not change, and 38.6% (n=236) among those whose attitudes remained the same (p<0.001). Similarly, a significant association was found between pneumococcal vaccination status and changes in vaccination attitudes during the pandemic; pneumococcal vaccination rates were 46.5% (n=317) among those whose views changed due to the pandemic, 35.0% (n=177) among those whose views did not change, and 56.7% (n=347) among those whose attitudes remained the same (p<0.001).

Figure 2 compares participants’ vaccination trends for seasonal influenza and pneumococcal vaccines before and after the pandemic. For both vaccines, the largest proportion consisted of individuals who reported not being vaccinated, with rates of 66.8% (n=1,203) for seasonal influenza and 53.3% (n=959) for PCV. For the seasonal influenza vaccine, 20.9% (n=378) of participants reported being vaccinated before the pandemic, while 12.3% (n=219) reported being vaccinated after the pandemic. In contrast, for the PCV, the post-pandemic vaccination rate (31.7%; n=571) was markedly higher than the pre-pandemic rate (15.0%; n=270), indicating a significant increase in demand for pneumococcal vaccination after the pandemic.

In this study, adult vaccination status and factors influencing vaccination behaviors among individuals aged 65 years and older were evaluated. It was observed that seasonal influenza and pneumococcal vaccines were administered at higher rates compared with other vaccines, whereas the herpes zoster vaccine remained at a very low level. The findings are generally consistent with both national and international literature and indicate that vaccination rates among the elderly population have still not reached the desired levels.

In a study conducted in Türkiye, vaccination rates for influenza, pneumococcal, and herpes zoster vaccines were reported as 21.8%, 4.3%, and 1.8%, respectively [7]. Similarly, a study conducted in 2010 reported that 51.5% of individuals aged over 65 years had received the influenza vaccine within the previous year, whereas only 16.5% had received the pneumococcal vaccine within the past five years [10]. In a larger sample study carried out between 2017 and 2018, the most frequently administered vaccine among 2,294 individuals aged over 65 years was influenza (33.7%), followed by adult-type diphtheria–tetanus (13.3%) and pneumococcal (7.9%) vaccines [11]. In another study conducted during a similar period, 33.94% of 303 individuals aged 65 years and older had received the influenza vaccine, 9.91% the pneumococcal vaccine, and 1.34% the tetanus vaccine; moreover, the vast majority of vaccinated individuals (94.42%) had preferred the influenza vaccine [12]. The pneumococcal vaccination rate of 46.7% observed in our study may be attributable to increased awareness generated by the pandemic.

Similarly, pneumococcal vaccination rates among individuals aged ≥65 years have been reported to range between 39% and 76% in Australia, while in the United States the pneumococcal vaccination rate among individuals aged 19–64 years in risk groups has been reported to be only 23% [13,14]. Our seasonal influenza vaccination rate of 33.2% is lower than the 46% reported in the United States but higher than rates reported in Türkiye. This finding suggests that, although progress has been made in vaccination practices in our country, vaccination coverage remains far from the desired targets.

The literature indicates that influenza and pneumococcal infections cause significant morbidity and mortality among older adults and that prevention is critically important in this population due to existing risk factors [5,8,9,15–17]. In our study, significantly higher seasonal influenza and pneumococcal vaccination rates among individuals with chronic disease, pulmonary disease, diabetes, or cardiovascular disease are consistent with these findings. Indeed, it has been reported that both influenza and pneumococcal vaccines reduce complications and hospitalizations among individuals with chronic obstructive pulmonary disease (COPD), and that vaccination rates are higher in the presence of chronic disease [5,15]. This relationship between comorbidities and vaccination underscores the decisive role of awareness and physician recommendations in high-risk groups [5,13,15,17].

In addition, influenza infection has been shown to have serious consequences not only for the respiratory system but also for the cardiovascular system. In the study by Smeeth et al., no increase in cardiovascular events was observed following seasonal influenza vaccination; however, the risk of acute cardiovascular events increased fivefold and the risk of stroke increased threefold within the first three days following a respiratory tract infection [6]. Similarly, the systematic review by Warren-Gash et al. provided strong evidence that influenza infection triggers acute myocardial infarction and cardiovascular mortality [7]. These findings suggest that influenza vaccination may indirectly reduce the risk of cardiovascular events, particularly among older individuals with cardiovascular comorbidities.

Accordingly, the association observed in our study between the presence of chronic disease and higher vaccination rates is consistent with clinical outcomes reported in the literature and supports the notion that vaccination in high-risk groups may reduce not only infectious complications but also cardiovascular events that contribute to mortality. Nevertheless, the persistently suboptimal vaccination rates in the general population remain noteworthy.

In our study, a significant association was found between educational level and vaccination status. Higher vaccination rates among individuals with a high school education or higher are consistent with literature demonstrating that education positively influences vaccination behaviors [9,14]. This may be explained by greater awareness of the protective effects of vaccines among individuals with higher educational attainment. In addition, the finding that Td vaccination rates were higher among individuals who had received influenza and pneumococcal vaccines suggests a clustering tendency in vaccination behaviors. The literature similarly reports that individuals who accept one vaccine are more likely to receive other adult vaccines, which is in line with our findings [9,18]. This result highlights the importance of a “vaccine bundling” approach in family medicine practice, in which multiple vaccines are recommended during the same visit.

The onset of the COVID-19 pandemic in Türkiye in March 2020 and the implementation of population-level interventions worldwide and nationally—such as social distancing, mask use, hygiene measures, school closures, and remote working—aimed at reducing SARS-CoV-2 transmission also markedly reduced the circulation of influenza and other respiratory viruses [19]. Indeed, compared with previous influenza seasons, the number of detected influenza and other respiratory viruses during the 2020/21 influenza season reached the lowest levels ever recorded both globally and in Türkiye [19]. Under these conditions, a reduction in perceived risk of influenza infection and a consequent decline in vaccination demand render low seasonal influenza vaccination rates an expected finding.

n a study conducted in Türkiye, vaccination rates for influenza, pneumococcal, and herpes zoster vaccines were reported as 21.8%, 4.3%, and 1.8%, respectively [7]. Similarly, a study conducted in 2010 reported that 51.5% of individuals aged over 65 years had received the influenza vaccine within the previous year, whereas only 16.5% had received the pneumococcal vaccine within the past five years [10]. In a larger sample study carried out between 2017 and 2018, the most frequently administered vaccine among 2,294 individuals aged over 65 years was influenza (33.7%), followed by adult-type diphtheria–tetanus (13.3%) and pneumococcal (7.9%) vaccines [11]. In another study conducted during a similar period, 33.94% of 303 individuals aged 65 years and older had received the influenza vaccine, 9.91% the pneumococcal vaccine, and 1.34% the tetanus vaccine; moreover, the vast majority of vaccinated individuals (94.42%) had preferred the influenza vaccine [12]. The pneumococcal vaccination rate of 46.7% observed in our study may be attributable to increased awareness generated by the pandemic.

Similarly, pneumococcal vaccination rates among individuals aged ≥65 years have been reported to range between 39% and 76% in Australia, while in the United States the pneumococcal vaccination rate among individuals aged 19–64 years in risk groups has been reported to be only 23% [13,14]. Our seasonal influenza vaccination rate of 33.2% is lower than the 46% reported in the United States but higher than rates reported in Türkiye. This finding suggests that, although progress has been made in vaccination practices in our country, vaccination coverage remains far from the desired targets.

The literature indicates that influenza and pneumococcal infections cause significant morbidity and mortality among older adults and that prevention is critically important in this population due to existing risk factors [5,8,9,15–17]. In our study, significantly higher seasonal influenza and pneumococcal vaccination rates among individuals with chronic disease, pulmonary disease, diabetes, or cardiovascular disease are consistent with these findings. Indeed, it has been reported that both influenza and pneumococcal vaccines reduce complications and hospitalizations among individuals with chronic obstructive pulmonary disease (COPD), and that vaccination rates are higher in the presence of chronic disease [5,15]. This relationship between comorbidities and vaccination underscores the decisive role of awareness and physician recommendations in high-risk groups [5,13,15,17].

In addition, influenza infection has been shown to have serious consequences not only for the respiratory system but also for the cardiovascular system. In the study by Smeeth et al., no increase in cardiovascular events was observed following seasonal influenza vaccination; however, the risk of acute cardiovascular events increased fivefold and the risk of stroke increased threefold within the first three days following a respiratory tract infection [6]. Similarly, the systematic review by Warren-Gash et al. provided strong evidence that influenza infection triggers acute myocardial infarction and cardiovascular mortality [7]. These findings suggest that influenza vaccination may indirectly reduce the risk of cardiovascular events, particularly among older individuals with cardiovascular comorbidities.

In our study, a significant association was found between educational level and vaccination status. Higher vaccination rates among individuals with a high school education or higher are consistent with literature demonstrating that education positively influences vaccination behaviors [9,14]. This may be explained by greater awareness of the protective effects of vaccines among individuals with higher educational attainment. In addition, the finding that Td vaccination rates were higher among individuals who had received influenza and pneumococcal vaccines suggests a clustering tendency in vaccination behaviors. The literature similarly reports that individuals who accept one vaccine are more likely to receive other adult vaccines, which is in line with our findings [9,18]. This result highlights the importance of a “vaccine bundling” approach in family medicine practice, in which multiple vaccines are recommended during the same visit.

The onset of the COVID-19 pandemic in Türkiye in March 2020 and the implementation of population-level interventions worldwide and nationally—such as social distancing, mask use, hygiene measures, school closures, and remote working—aimed at reducing SARS-CoV-2 transmission also markedly reduced the circulation of influenza and other respiratory viruses [19]. Indeed, compared with previous influenza seasons, the number of detected influenza and other respiratory viruses during the 2020/21 influenza season reached the lowest levels ever recorded both globally and in Türkiye [19]. Under these conditions, a reduction in perceived risk of influenza infection and a consequent decline in vaccination demand render low seasonal influenza vaccination rates an expected finding.

Our findings demonstrate that the COVID-19 pandemic created a pronounced “awareness effect” on adult immunization. The increase in pneumococcal vaccination rates to 31.7% after the pandemic—nearly doubling pre-pandemic levels—and the rise in influenza vaccination to 12.2% suggest strengthened motivation for protection against respiratory infections. Similarly, the literature reports an increase in the number of adults who received or planned to receive influenza and pneumococcal vaccines during the pandemic compared with previous seasons [20]. In a study conducted in Türkiye, 84.3% of individuals aged over 65 years stated that the pandemic had positively influenced their general attitudes toward vaccination, supporting this increase in awareness [21]. In a population-based study conducted in Taiwan, individuals with high levels of knowledge about COVID-19 were shown to have significantly increased tendencies to receive influenza and pneumococcal vaccines [22]. In our study, near-universal influenza and pneumococcal vaccination rates among individuals who perceived themselves as being in a risk group, were vaccinated due to chronic disease, or believed in the protective effects of vaccines further demonstrate that the pandemic was a powerful trigger for adult immunization. Taken together, these findings emphasize that the COVID-19 pandemic has acted as an important catalyst for increasing vaccine awareness in the adult population and that strengthening national adult immunization strategies is necessary to sustain this increase [8,23,24].

Indeed, a study conducted among hospitalized COVID-19 patients aged 65 years and older demonstrated that adult vaccination status was a determinant of disease severity and mortality. In that study, mortality among unvaccinated individuals was 2.2 times higher than among those who had received at least two vaccine doses, and mortality rates decreased progressively with increasing numbers of vaccine doses [25]. This finding supports the notion that the pandemic represents not only an opportunity to improve acceptance of COVID-19 vaccination but also a critical foundation for strengthening the uptake of other adult vaccines such as influenza and pneumococcal vaccines.

The extremely low herpes zoster vaccination rates observed in our study suggest deficiencies in awareness, access limitations, and reimbursement issues within adult immunization programs in our country. The literature similarly reports that cost and access barriers underlie the low uptake of the herpes zoster vaccine [13,26]. Our findings indicate that adult vaccines other than influenza and pneumococcal vaccines remain insufficiently utilized in Türkiye. Therefore, integrating the herpes zoster vaccine—alongside seasonal influenza and pneumonia vaccines—into routine immunization programs for older adults, particularly those with chronic diseases, is of critical importance for providing comprehensive protection and reducing the burden of infectious diseases.

In this study, adult vaccination status among individuals aged 65 years and older was comprehensively evaluated. The highest vaccination rates were observed for pneumococcal and seasonal influenza vaccines, whereas the herpes zoster vaccine uptake was found to be extremely low. Vaccination rates were significantly higher among individuals with higher educational levels, those with chronic diseases, and those who believed in the protective effects of vaccines. The COVID-19 pandemic was found to have markedly increased acceptance of pneumococcal and influenza vaccines, and near-complete adherence to both vaccines among individuals who perceived themselves as being in a risk group was particularly noteworthy.

These findings indicate that adult vaccination rates among older individuals remain below the targeted levels; however, strengthening health literacy, increasing physician recommendations, and effectively utilizing the post-pandemic window of heightened awareness may help improve these rates. In particular, developing promotion and accessibility strategies for vaccines with low awareness, such as the herpes zoster vaccine, is of great importance. Strengthening adult immunization programs in primary healthcare settings, providing regular information to risk groups, and facilitating access to vaccines will contribute to increasing vaccination coverage among the elderly population.

Strengths of the Study

The large sample size provided high statistical power and allowed reliable detection of associations.
Face-to-face data collection minimized missing data and enhanced data accuracy.
Comprehensive evaluation of multiple adult vaccines enabled a broad assessment of vaccination behavior in older adults.
The study assessed the impact of the COVID-19 pandemic on vaccination attitudes, offering timely and relevant insights for public health planning.

Limitations of the Study

The single-center design may limit the generalizability of the findings to the wider elderly population.
Vaccination status and reasons for vaccination were based on self-reported data, which may be subject to recall bias.
The descriptive design does not allow causal inferences regarding factors influencing vaccination behavior.

Participant Consent Statement: Ethical approval for this study was obtained from the Clinical Research Ethics Committee of the Health Practice and Research Center of SBÜ Şişli Hamidiye Etfal Training and Research Hospital (approval date: 02/03/2021; approval number: 1830). All participants were informed about the study objectives and procedures, and written informed consent was obtained from all participants prior to participation.

Author Contribution

İlknur Demir (I.D.):Conceptualization; Methodology; Formal analysis; Data curation; Investigation; Writing – original draft; Writing – review & editing; Visualization.Güzin Zeren Öztürk (G.Z.O.):Conceptualization; Methodology; Supervision; Validation; Writing – review & editing.Beray Gelmez Taş (B.G.T.):Methodology; Investigation; Writing – review & editing.All authors read and approved the final version of the manuscript and agree to be accountable for all aspects of the work.

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Table 1. Influenza And Pneumococcal Vaccination Rates According To Participants’ Reasons For Vaccination
Reason For Vaccination	All Participants (n=1800) n (%)		Influenza Vaccine (n=597)			Pneumococcal Vaccine (PCV) (n=841)
			Yes	No	p	Yes	Hayır	p
Belief İn The Protective Effect Of The Vaccine	Yes	989(54,9)	279(95,5)	13(4,5)	0,00	482(100)	-	0,00
Belief İn The Protective Effect Of The Vaccine	No	811(45,1)	318 (21,1)	1190(78,9)	0,00	359(27,2)	959(72,8)	0,00
Perceiving Oneself At Risk Due To Age	Yes	614(34,1)	203(93,5)	14(6,5)	0,00	259(100)
Perceiving Oneself At Risk Due To Age	No	1186(65,9)	394(24,9)	1189(75,1)	0,00	582(37,8)	959(62,2)
Vaccinated Due To Chronic Disease	Yes	201(11,2)	98(%99,0)	1(%1,0)	0,00	111(100)		0,00
Vaccinated Due To Chronic Disease	No	1599(88,8)	499(29,3)	1202(70,7)	0,00	730(43,2)	959(56,8)	0,00

No competing interests reported.

Adult Vaccination Status in the Elderly Population: A Cross-Sectional Evaluation

Status:

Version 1

Abstract

Figures

Introduction

Materials and Methods

Results

Discussion

Conclusion

Declarations

Author Contribution

References

Table

Additional Declarations

Status:

Version 1