COVID-19 Vaccine Booster Hesitancy among Healthcare Workers: A Retrospective Observational Study in Singapore

Abstract

Background: COVID-19 booster uptake remained poor among healthcare workers (HCW) despite evidence of improved immunity against Delta and Omicron variants. While most studies used a questionnaire to assess hesitancy, this study aimed to identify factors affecting booster hesitancy by examining actual vaccine uptake across time. Method: COVID-19 vaccination database records among HCW working at seven Singaporean public primary care clinics between January to December 2021 were extracted, with sex, profession, place of practice, vaccination type, and dates. Time to booster was calculated from the date of vaccination minus date of eligibility. Chi-square test was used to compare the relationship between first dose and booster hesitancy, Kaplan–Meier method and log-rank test were adopted to evaluate differences in cumulative booster uptake. Multivariate Cox regression was used to investigate predictors for timely booster vaccination. Vaccination rate was charted across time and corroborated with media releases pertaining to legislative changes. Results: A total of 877 of 891 (98.9%) primary care HCW were fully vaccinated, 73.8% of eligible HCW had taken the booster. HCW were less booster hesitant [median 16 (5–31.3) days] compared to the first dose [median 39 (13–119.3) days]. First dose-hesitant HCW were more likely to be booster hesitant (OR = 3.66, 95%CI 2.61–5.14). Adjusting for sex, workplace, and time to first dose, ancillary (HR = 1.53, 95%CI 1.03–2.28), medical (HR = 1.8, 95%CI 1.18–2.74), and nursing (HR = 1.8, 95%CI 1.18–2.37) received boosters earlier compared with administrative staff. No temporal relationship was observed between booster uptake, legislative changes, and COVID-19 infection numbers. Conclusion: Vaccine hesitancy among HCW had improved from first dose to booster, with timely booster vaccination among medical and nursing staff. Tailored education, risk messaging, and strategic legislation might help to reduce delayed booster vaccination.

Perception of COVID-19 Booster Dose Vaccine among Healthcare Workers in India and Saudi Arabia

“…In our study, logistic regression showed that participants who were willing to receive a CBD believed that it has adverse reactions, that mix-matching the booster dose is safe and effective, and that the booster vaccine can reduce the spread of COVID-19. In Singapore, 98.9% of HCWs were completely immunized, and 73.8% of those eligible had taken a booster dose, which helped to decrease community spread and keep the mortality rate low [ 47 ].…”

Prevalence and factors associated with not receiving the booster dose of the COVID-19 vaccine in adults in Latin America and the Caribbean

“…However, as with the initial doses, the vaccination intent of the booster dose is not universal [ 11 , 12 ]. Studies in Poland, Jordan, China, Denmark, Italy, and Singapore showed that between 44.6% and 95.5% of the general population intend to receive a booster dose [ [13] , [14] , [15] , [16] , [17] , [18] , [19] ]. This intention is influenced by aspects such as confidence in vaccines, fear of side effects, history of chronic diseases, gender, age or level of education of the people [ [13] , [14] , [15] , [16] , [17] , [18] ].…”

Predictors of second COVID-19 booster dose or new COVID-19 vaccine hesitancy among nurses: a cross-sectional study

“…Since literature suggests a predictable relationship between the intentions of healthcare workers and their subsequent behavior (Eccles et al, 2006), high levels of nurses’ vaccine hesitancy toward a second booster dose/new COVID-19 vaccine could be a significant threat for healthcare systems over the winter period. Studies in the USA, Czech, Saudi Arabia, and Singapore estimated healthcare workers hesitancy toward the first booster dose and found a hesitancy percentage of 33%, 28.8%, 44.7%, and 26.2% respectively (Alhasan et al, 2021; Chrissian et al, 2022; Klugar et al, 2021; Koh et al, 2022). The situation is even worse if we consider that the median value of hesitancy toward the first booster is higher among healthcare workers compared to the general population (31% vs. 22.1%) (Al-Qerem et al, 2022; Chu et al, 2022; Lai et al, 2021; Lounis et al, 2022; Miao et al, 2022; Paul & Fancourt, 2022; Rzymski et al, 2021; Wu et al, 2022; Yoshida et al, 2022).…”

“…Since there are no studies regarding nurses’ hesitancy toward a second booster dose or a new COVID-19 vaccine, we based on studies that estimate healthcare workers hesitancy toward the first booster in order to find out the minimum sample size (Alhasan et al, 2021; Chrissian et al, 2022; Klugar et al, 2021; Koh et al, 2022). These studies found that median healthcare workers hesitancy toward the first booster was 31%.…”

“…Until now, levels of second booster/ new COVID-19 vaccine hesitancy among healthcare workers are not investigated. Moreover, only a few studies have estimated the vaccine hesitancy towards the first booster dose among healthcare workers (Alhasan et al, 2021; Chrissian et al, 2022; Klugar et al, 2021; Koh et al, 2022). Also, literature is scarce regarding the factors that affect healthcare workers decision to accept the first COVID-19 booster dose (Alhasan et al, 2021; Chrissian et al, 2022; Klugar et al, 2021).…”