This paper was the first to examine the role of religiosity in COVID-19 vaccination rate using a country-level comparison. We used data extracted from nine secondary data sources from 90 countries. The results show that religiosity at the level of cross-country comparison analyses is not associated with the COVID-19 vaccination rate, except for Christianity. Our results have shown that the proportion of Christians in a given country was negatively related to the vaccination rate after accounting for socio-economics and cultural factors. The ratio of Muslims, Buddhists, and Hindus in a given country was not associated with the vaccination rate, nor was the proportion of nonbelievers, the importance of religion, and freedom of expression and belief. Our analyses demonstrated that HDI was the strongest predictor of COVID-19 vaccination rate. Unemployment rate and indulgence (cultural factor) were significant determinants of vaccination rate, but only for separate regression analyses conducted for specific religions.
Our analyses indicated that only Christianity, at the country level of analysis, was predictive of the actual vaccination rate. No such effects were observed for other religions and other religion-related variables, i.e., the importance of religion and freedom of expression and belief. These results are consistent with previous research showing that religiosity is not significantly related to COVID-19 vaccination acceptance (Guidry et al., 2021; Freeman et al., 2020; Kilic et al., 2021; Sherman et al., 2021) and are in opposition to findings showing that religiosity is negatively related with vaccination against COVID-19 (e.g., Murphy et al., 2021; Olagoke et al., 2020). Although negative correlations between different religions and vaccination rate or positive correlations between freedom of belief and vaccination rate have been observed, most of them become non-significant after introducing socioeconomic and culture variables into a regression model. This shows that researchers should include socioeconomic and cultural variables in studies on the relation between religion and vaccination (or health) to avoid spurious correlations.
Negative relationships between religiosity and vaccination are usually explained by the fact that religiosity is associated with a lack of trust in science (Simpson et al., 2016), which was demonstrated for Muslims (Islam et al., 2021) Hindus, and Christians (Simpson et al., 2016). However, these studies suggest that we cannot solely explain the results of our study through a lack of trust in science among Christians, as the same pattern was observed among Muslims and Hindus. The finding that only Christianity is associated with vaccination suggests that specific mechanisms related to a particular religion may explain this relationship. So there may be specific anti-vaccination attributes of Christianity, and pro-vaccination attributes of Islam, Buddhism, and Hinduism that compensate for the negative relationship between religiosity and trust in science.
Our findings that Christianity is negatively related to vaccination rate may be surprising since the official stance of most Christian denominations is either in favor of vaccination or, at the very least, not against it (King, 2021). The heads of the Catholic, Protestant and Orthodox churches have declared that vaccination against COVID-19 is compatible with the doctrines of the faith and even morally desirable (Thinane, 2022). However, some Christians and members of the clergy are against COVID-19 vaccination due to the possibility of some vaccines being produced from aborted fetus tissue, which violates the Christian viewpoint on abortion (King, 2021; Thinane, 2022). An example of this, as elucidated by Glenza and Pengelly (2021), is the condemnation of the Johnson & Johnson COVID-19 vaccine as being "morally compromised" by some of the heads of the Roman Catholic church in the USA, even though the producer stressed that there was no fetal tissue in their vaccine. There are some smaller Christian denominations where vaccines are considered incompatible with the religious doctrine, up to several decades ago or till present day e.g., Amish; Church of Christ, Scientist; Dutch reformed congregations; Jehovah's Witnesses; Church of the First Born (Grabenstein, 2013). Corcoran et al. (2021) pointed to Christian nationalists, a group of very conservative believers, as one of the US's most anti-vaccine and anti-scientific groups.
In Islam, vaccination is neither forbidden nor inconsistent with religious laws. Since preserving life is aligned with preserving religion, receiving a COVID-19 vaccination is a form of compliance with Sharia law (Mardian et al., 2021; Sholeh & Helmi, 2021). Many imams and Muslim organizations encourage the faithful to get vaccinated against COVID-19 (King, 2021; Thinane, 2022). Even before the COVID-19 pandemic, many Islamic leaders announced fatwas describing how vaccination is consistent with Islamic principles (Grabenstein, 2013).
The essential precept of Buddhism prohibits taking of life and mandates moral commitment to not destroy life. Therefore, Buddhists particularly understand and stress the importance of saving lives through vaccination (Thinane, 2022). Buddhism interprets treatment as an act of mercy, and thus the prevention of diseases through vaccination can be perceived similarly (Grabenstein, 2013). Moreover, there are many historical reports of medical treatments by Buddhists based on vaccination (Cha, 2012). The link between Buddhism and vaccination was exploited by Bhutan, where the government collaborated with the religious authorities by choosing the correct date to start vaccination, the right first person to be vaccinated, and the right mantra, which was a special prayer in warding off diseases (Rocha, 2021).
Similarly, in Hinduism, there is evidence of a centuries-old practice of immunization, which leads to the belief that vaccination is an act of worship, with a lack of conformity enraging the Gods (Sweetman & Malik, 2016). The idea of vaccination is described in the religious texts of the Harivamsa Purana and is attributed to Dhanwantari, the God of Ayurveda (the God of the traditional system of Hindu medicine, Maharaj, 2021)
Our results are relevant to the investigation of the relationship between religiosity and health. We showed that HDI was positively related to vaccine rate - the higher the HDI, the higher the vaccine rate was in most countries. Thus, people from more developed countries are more likely to get vaccinated, possibly due to higher income, better health services, and education, compounding HDI factors. Previous studies indicate that HDI also influences overall vaccine rate and vaccine hesitancy with other vaccines (de Cantuária Tauil et al., 2016; García-Toledano et al., 2021; Hayman, 2019). García-Toledano et al. (2021) explained that vaccination is usually more regulated in countries with higher HDI, and that these societies are more aware of the importance of vaccination. That, in turn, is the effect of better education systems and a greater number of resources that can be used in health promotion. Countries with lower HDI might also have trouble affording the vaccine. Furthermore, similar to prior studies (e.g., Guo et al., 2022) on the influence of socio-economic factors on vaccination, the unemployment rate was also negatively related to the COVID-19 vaccine rate, but only for separate regression analyses conducted for specific religions. The remaining sociodemographic variables used in this study, sex ratio and media age, had no significant relation with vaccine rate.
Despite having high correlations with remaining variables, culture dimensions had no relation to vaccine rate in the model, excluding the indulgence dimension. Indulgence was only significant in the model with Christianity after accounting for religious variables. Indulgence relates to enjoying life and free gratification (Hofstede Insights, 2022). Restraint stands in opposition to indulgence, and relates to suppressed needs, gratification, and high regulation with social norms. The indulgence dimension was not previously explored in the context of vaccination. Still, research on national culture and COVID-19 shows that more indulgent countries might have fewer deaths (Windsor et al., 2020), but simultaneously experience more issues inciting people to conform with COVID-19 rules (Gokmen al., 2021; Wang, 2021). This is not inconsistent with our results since indulgent societies might have a greater desire to restore normalcy, i.e not have to follow COVID-19 rules such as social distancing and be able to engage in various social activities freely, and are therefore more likely to get vaccinated.
Our study has some practical implications. We suggest that Christian religious institutions should be used for disseminating information about COVID-19 vaccination safety and outcomes. It is crucial for practitioners and researchers to engage in discussions with religious leaders and congregants to better understand specific concerns about the vaccine, such as the vaccine being potentially derived from human tissue. This will enable the creation of educational messages aimed at religious people that are compatible with their beliefs(Shelton, 2013), that is, for instance, messages explaining in detail how vaccines are made and what they consist of. Finally, given the role religious belief plays in the vaccination process, healthcare providers might have to address vaccine concerns among individuals with strong beliefs.