Role of Gender in Hesitancy Toward the COVID-19 Vaccine Beyond Medical Students ^†

Dear Editor,

We thank Dr. Mungmunpuntipantip and Dr. Wiwanitkit for their comment on our article [1]. The authors refer to female gender as a potential main predictor of COVID-19 vaccine hesitancy among medical students [2].

In a systematic review on vaccination hesitance including 422 studies (51% on COVID-19), the authors defined vaccination hesitancy as a psychological condition marked by indecisiveness that individuals may encounter when faced with the decision to get vaccinated or not [3].

Gender has been reported to be associated with vaccine hesitancy in several studies, albeit with conflicting results. For example, in the study by Azimi et al., the hesitancy rate in male medical students was higher than in females (64% vs 52.2%) [4]. In addition, in the study by Omer et al., a moderate level of vaccine hesitancy among the medical students was observed, with no difference between males and females being reported [5]. Of note, among the 5C model used in the above mentioned study (vaccine confidence, complacency, constraints, calculation, and collective responsibility), female gender was significantly associated only with constraints (p=0.003) [5]. Furthermore, in the study by Elgalil et al., where only female students were included, the hesitancy rate among female medical and nursing students was as low as 24.4% [6].

Regarding our study [1], we further analyzed COVID-19 vaccination hesitancy between male and female medical students. According to our analysis, 13/96 male students (15.5%) and 37/167 female students (22.15%) were considered hesitant to receive SARS-COV-2 vaccination, but this difference between gender ratios was not significant (p=0.08).

It should be mentioned that apart from gender, several other factors may play a role in COVID-19 vaccine hesitancy. These may include societal and cultural influences, information sources and health literacy, misinformation, psychological factors, previous healthcare experiences, as well as peer influence and social networks [7,8,9,10].

Interestingly, in a UK (n=2025) and Ireland (n=1041) data collection study, individuals who were hesitant or resistant to the COVID-19 vaccine were distinguished from their vaccineaccepting counterparts by demonstrating greater self-interest, heightened skepticism towards experts and authority figures (such as scientists, healthcare professionals, and the state), a higher likelihood of holding strong religious beliefs (potentially linked to skepticism of the scientific worldview), and a propensity for conspiratorial and paranoid beliefs, indicative of a lack of trust in others' intentions [7]. Additionally, this group was more inclined to believe that their lives were primarily under their own control, exhibited a preference for societies with hierarchical structures and authoritarian tendencies, and displayed increased intolerance towards migrants in society [7]. Furthermore, they exhibited a more impulsive thinking style and possessed a personality characterized by greater disagreeableness, heightened emotional instability, and lower conscientiousness. These factors collectively contributed to their distinct profile compared to those more accepting of the COVID-19 vaccine [7].

Several studies have examined the influence of gender on the perception of COVID-19 vaccine beyond medical students. In brief, COVID-19 vaccine hesitancy among 269 New Jersey secondary educational professionals demonstrated that 86.3% of males and 77.1% of females were likely to get a booster (p=0.05, for the comparison between males and females) [11].

An interesting issue that should be addressed is the COVID-19 vaccination hesitancy among LGBTQ+ (lesbian, gay, bisexual, transgender, queer, and other gender minority individuals) community. A recent study showed that the majority of 3642 LGBTQ+ participants exhibited positive attitudes and perceptions toward the COVID-19 vaccine. However, negative COVID19 vaccine acceptance and accessibility were notably associated with factors such as medical mistrust, racial identity, and gender identity [12].

A recent meta-analysis including 18 studies reporting on COVID-19 vaccination in slum and/or underserved communities found that the vaccine acceptance rate was 58%, the hesitancy 29% and the uptake 23% [13]. Of note, COVID-19 vaccine acceptance, hesitancy, and uptake exhibited substantial variations based on region, study population, and study year. In brief, Asia and Africa reported higher acceptance rates compared to the Americas, whereas the Americas demonstrated greater vaccine uptake compared to Asia. These differences can be attributed to diverse vaccination policies across countries, including mandatory vaccination, travel restrictions and lockdowns [13].

Of importance, the average COVID-19 vaccination hesitancy prevalence globally in a total sample of 76,471 healthcare workers from 21 countries was 22.51% (4.3-72%) [14]. In this study, male gender was found to be an enabling factor in 25 out of 35 studies (71.4%), indicating a higher willingness for COVID-19 vaccines by males [14]. It should be noted though that currently, majority of data stem from surveys which are studies with high risk of bias. Moreover, a potential explanation regarding this observation is that initially there were few data and misinformation regarding the potential effect of COVID-19 vaccines in conception, pregnancy and breastfeeding [15].

Overall, although male healthcare workers may be less hesitant to receive SARS-CoV-2 vaccination, current evidence supports that gender does not represent a predicting factor of SARS-CoV-2 vaccination hesitance among the medical students.