Willingness to accept herpes zoster vaccines and the influencing factors in China - BMC Infectious Diseases - BMC Infectious Diseases

One year after being introduced into the domestic market, the first vaccine used against HZ in mainland China, HZV has now been supplied in over 200 cities. The number of HZ vaccinees remains very low, which is similar to the situation in the USA in the initial 2–3 years when HZV was recommended to the public in 2006. Since the evidence related to the HZ vaccine uptake rate is limited [17], we did not consider the vaccination rate of HZV as the outcome variable; about 50% of participants showed hesitancy for HZV. The present study identified the demographic factors related to HZV willingness and reasons for vaccination hesitancy. The public presented common main factors irrespective of their attitudes.

In the current survey, 43.02% of participants intended to be vaccinated, 30.22% declined, and 26.76% were hesitant. This rate (43.02%) was in accordance with a previous study in Shanghai (49.64%) before HZV was available [12], but the willingness to get HZV was 26% higher compared to another Shanghai study conducted in late 2020 with the elderly's intention of HZ vaccination (16.57%) [11]. This difference could be attributed to the different populations, methods of response, and the positive impact on all vaccines due to COVID-19 vaccination. However, a huge gap between willingness and behavior in the vaccination is notable since < 25% (397/1651) of willing participants have received HZV.

As expected, participants from rural areas showed strong unwillingness largely due to access and affordability issues concerning HZV. We also found that low personal income has a strong influence on vaccination hesitancy since HZV is a self-paid vaccine in China. However, those with personal monthly incomes < 3000 RMB expressed a strong willingness to HZV. This unexpected result hinted that the unanticipated COVID-19 pandemic might have a significant impact on the normal life of the underclass, and the acceptance of COVID-19 vaccine can be split over into the HZV, after the free COVID-19 vaccination program in China. In addition, HZV is relatively new in China, it is possible that most people have no clear idea how much it cost to be vaccinated against HZ. Further studies are needed to support this finding, especially for studies on their willingness to pay. To translate the strong willingness into actions, multipronged social support strategies should be executed; for instance, introducing HZV into insurance or promoting free vaccines for high-risk patients [18]. Several studies have verified that the national or government-supported vaccine program and insurance cost-sharing help in increasing the acceptance and actual uptake [19]. Accumulating evidence indicated that the COVID-19 pandemic has changed the public attitude positively regarding the vaccines not limited to COVID-19 [15, 16], which can be considered remarkable among low-income populations in our study. This finding necessitates further studies to substantiate this conclusion in the future.

The uncommon fact consistent with the results of Zein et al. was that the odds of refusal of getting HZ vaccination increased slightly with high education level [20]. Graduate degree holders (Master's and Ph.D.) presented a 1.29-fold higher probability of refusal to get HZV than participants with senior high school or lesser diploma (OR 1.29, 95% CI: 1.02–1.63). Although the statistical significance was only borderline, indicating that the refusal of the vaccine was not arbitrary but may be associated with specific education. Higher education experience may boost their self-efficacy associated with complacency and determines the degree of hesitancy [21]. Such finding informs practitioners that it should not to be assumed that higher education is associated with better health literacy. Tailored health educational programs about HZV are needed for elders with different educational background.

To achieve satisfactory coverage, the actions that can prompt the elderly need to be considered seriously. The recommendation from other people was chosen as a decisive factor among those ≥ 50-years-old [22] since they are isolated compared to younger generations with respect to accurate, timely, and professional health knowledge. In practice, under American Advisory Committee on Immunization rapid approval, two-dose completion of RZV within one year exceeds that for other vaccine series used in American and Canadian elderly (80% and 74.9%, respectively) [23]. Given the importance of receiving recommendations for the HZ vaccine, people around them play a critical role in this process. Enhancing the clinicians' responsibilities and abilities to recognize their patients' demands [24], carrying out community education, and informing their grown-up children could potentially increase the chance of recommendations to the elderly [17]. Especially, healthcare providers are the primary personnel who may offer immunization information and recommendation. Their role is that of a population health practitioner focusing not only on the diagnosis and treatment but on disease prevention and health promotion. Typically, the recommendation or vaccination history of other vaccines, such as like influenza and pneumococcal infection, are beneficial to HZ vaccination; also, speaking about immunization is beneficial. Evidentially, 69.5% of the refusals reversed to accept HZV following the physician's recommendation in South Korea [25]. Moreover, confirming the safety of the vaccine and perceived severity and susceptibility to HZ prompted the elders to get HZV. These elements may help the healthcare providers to train their communication skills and content.

In our survey, 56.98% of participants might not have the HZV; among them, 53.04% definitely did not have the vaccine. Therefore, we confirmed the target population's obstacles to vaccination. These results might be useful in prioritizing the targeted actions aiming to achieve satisfied coverage rates. Fear of adverse reactions and concerns of effectiveness belongs to the confidence category and get more consensus than other factors, such as lack of knowledge and information. Providing health education and improving health literacy is an urgent requisite for elders than providing those with vaccination-related information, which should be taken as the second step. Although people have access to the vaccine, they would not accept it unless they have ample confidence in the safety and efficiency of the HZV. To alleviate the asymmetric information, both scientific and experience-based evidence needs to be presented to the elderly. Various ways of health education should be adopted as information sources for the Internet-savvy elderly, such as playing short videos on TikTok, broadcasting public health announcements on social media, and organizing peer education in their familiar community.

The strengths of this study are that we investigate the main reasons for being willing or not willing to be vaccinated in a large sample size of Chinese elderly. Nevertheless, the limitations cannot be ignored. First, the cross-sectional nature of the present study does not allow the comparison of changes in HZV intention from before to after the introduction of the vaccine in China. This could be carried out only by indirect comparison with limited published studies. Second, the online survey made it impossible for us to recruit those who have no access to the Internet and those who had difficulties reading or using mobile phones. Collecting data from the People's Daily Health media platform, where the adopters focus on their health, may induce selection bias and volunteer bias and lead to the overestimation of the coverage rate and the willingness to receive HZV. To weaken these unavoidable biases, our results emphasized the factors rather than numerical calculations.