Koh Sky Wei Chee, Tan Hwei Ming, Lee Wayne Han, Mathews Jancy, Young Doris
National University Polyclinics, National University Health System, Singapore 609606, Singapore.
Division of Family Medicine, Yong Loo Lin School of Medicine, National University of Singapore, Singapore 119228, Singapore.
Vaccines (Basel). 2022 Mar 17;10(3):464. doi: 10.3390/vaccines10030464.
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.
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.
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.
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.
尽管有证据表明加强针可增强对德尔塔和奥密克戎变种的免疫力，但医护人员对新冠病毒加强针的接种率仍然很低。虽然大多数研究使用问卷调查来评估犹豫程度，但本研究旨在通过检查不同时间的实际疫苗接种情况来确定影响加强针犹豫的因素。
提取了2021年1月至12月在新加坡七家公立基层医疗诊所工作的医护人员的新冠疫苗接种数据库记录，包括性别、职业、执业地点、疫苗类型和日期。从接种日期减去符合接种条件的日期来计算加强针接种时间。采用卡方检验比较首剂接种和加强针接种犹豫之间的关系，采用Kaplan-Meier方法和对数秩检验评估累积加强针接种率的差异。使用多变量Cox回归研究及时接种加强针疫苗的预测因素。绘制不同时间的接种率图表，并与有关立法变化的新闻稿进行核实。
891名基层医疗医护人员中有877名（98.9%）完成了全程接种，73.8%符合条件的医护人员接种了加强针。与首剂接种[中位数39（13-119.3）天]相比，医护人员对加强针的犹豫程度较低[中位数16（5-31.3）天]。首剂接种犹豫的医护人员更有可能对加强针接种犹豫不决（比值比=3.66，95%置信区间2.61-5.14）。在调整性别、工作场所和首剂接种时间后，辅助人员（风险比=1.53，95%置信区间1.03-2.28）、医疗人员（风险比=1.8，95%置信区间1.18-2.74）和护理人员（风险比=1.8，95%置信区间1.18-2.37）比行政人员更早接种加强针。在加强针接种率、立法变化和新冠病毒感染人数之间未观察到时间关系。
医护人员对疫苗的犹豫程度从首剂接种到加强针接种有所改善，医疗和护理人员及时接种了加强针。量身定制的教育、风险信息传递和战略立法可能有助于减少加强针接种延迟。
