Abstract
What is already known about this topic?
Public health workers (PHWs) were listed as a priority group recommended for influenza vaccination during the coronavirus disease 2019 (COVID-19) pandemic. Understanding the drivers of influenza vaccine hesitancy among PHWs can promote influenza vaccination in the COVID-19 pandemic.
What is added by this report?
The study found that 10.7% of PHWs were hesitant to get an influenza vaccination. Drivers associated with vaccine hesitancy were assessed based on “3Cs model.” The absence of a government or workplace requirement and concerns about vaccine safety were the biggest obstacles for PHWs to recommend influenza vaccination.
What are the implications for public health practice?
Interventions are needed to improve PHWs’ influenza vaccine coverage to prevent the co-circulation of influenza and COVID-19.
Keywords: Influenza vaccination, public health workers, vaccine hesitancy, vaccination willingness
Globally, influenza causes 3–5 million hospitalizations and 290,000–650,000 respiratory deaths each year (1). From February through August 2022, influenza activity was at its highest level compared to similar periods since the start of the coronavirus disease 2019 (COVID-19) pandemic globally (2). As the priority group recommended for influenza vaccination during the COVID-19 pandemic, healthcare workers (HCWs), including public health workers (PHWs), have a greater chance of contracting influenza viruses; this poses a greater risk of transmission (3). PHWs refer to those who are engaged in public health services and vaccination work in the Center for Disease Control and Prevention (CDC) system, community health service centers, or township health centers. Previous surveys have shown that willingness and influence factors of front-line staff involved in the work of influenza control are of higher concern (4-5). The research mainly focused on assessing PHWs’ attitudes toward influenza vaccination in 2022–2023. Univariate analysis and multivariable logistic regression analysis were used to evaluate factors associated with vaccine hesitancy. A total of 3,127 PHWs were surveyed. 10.7% were hesitant about influenza vaccination in the coming season. Multivariate logistic regression analysis found that PHWs who did not receive an influenza vaccine between September 2021 and April 2022 [odds ratio (OR)=5.08, 95% confidence interval (CI): 3.54–7.29] and PHWs who believed vaccination had no importance for health (OR=21.32, 95% CI: 10.15–44.80) were more likely to hesitate to get vaccinated. The results suggest that effective measures should be taken to strengthen the willingness of PHWs to vaccinate against influenza. This reduces the burden of the COVID-19 responding and medical facilities.
From September 16 to 26, 2022, a link to the questionnaire for the survey was posted on Listening to the Experts, a learning and communication platform that authenticates real identity information of registered users and was used by professionals in the field of vaccination in China (6). PHWs could voluntarily participate in the survey and forward it to their colleagues, but each participant could only answer once. As of September 30, 2022, the Listening to the Experts platform has over 650,000 PHW users, covering 31 provincial-level administrative divisions (PLADs) in China. Data on respondents’ sociodemographic characteristics, workplace interventions, knowledge of influenza vaccination, influenza vaccination history and attitudes towards recommending influenza vaccination were collected. The per capita gross domestic product (GDP) of each PLAD was obtained from the National Bureau of Statistics of China (7). Vaccine hesitancy refers to delay in acceptance or refusal of vaccination despite availability of vaccination services. According to the “3Cs model” of vaccine hesitancy (8), the impact of confidence, complacency, and convenience on hesitancy to receive influenza vaccination was analyzed and concerns of PHWs in recommending influenza vaccination were presented. The study protocol and questionnaire were approved by the Chinese Academy of Medical Sciences and Peking Union Medical College (No. CAMS&PUMC-IEC-2022-019, on March 14, 2022).
Univariate analysis included frequency and ratio calculations and Pearson’s chi-squared test for differences. Multivariate logistic regression was used to evaluate factors associated with intention to accept vaccination. ORs and 95% CIs were calculated. Alpha level was set at 0.05. Statistical analyses were performed using the Statistical Package for Social Sciences (SPSS, version 26.0, SPSS Inc, Chicago, IL, USA.).
A total of 3,145 PHWs from 28 PLADs participated in the survey, with 18 incomplete questionnaires excluded. Among the 3,127 respondents in China, 823 (26.3%) work at CDC systems, and 2,304 (73.7%) were from community or township health service centers. Nearly half had an intermediate professional title or above and 10.7% (336) had influenza vaccine hesitancy. In the 2021–2022 influenza season, 52.5% respondents (1,643/3,127) were vaccinated against influenza, including 64.9% (1,067/1,643) vaccinated at a community or township health service center, 21.4% (352/1,643) vaccinated at a hospital, 12% (197/1,643) vaccinated at a CDC vaccination clinic, and 1.6% (27/1,643) vaccinated elsewhere.
Of the 336 respondents with vaccine hesitancy, 22.3% (75/336) worked at CDC systems and 77.7% (261/336) worked at community or township health service centers. The analysis results based on the “3Cs model” illustrated that 43.45% of the respondents believed complacency, 24.88% believed confidence, and 20.79% believed convenience had an impact on vaccine hesitancy. In terms of complacency, 43.3% (146/336) believed that influenza infection would not cause serious illness and it did not matter if they were not vaccinated (Table 1).
Table 1. Reasons for influenza vaccine hesitancy among PHWs (Based on 3Cs model) in China, September 2022.
| Variable | Very unacceptable (%) | Unacceptable (%) | Acceptable (%) | Highly acceptable (%) | |
| Abbreviation: PHWs=public health workers. | |||||
| Convenience | |||||
| High prices | 37.8 | 21.1 | 27.4 | 13.7 | |
| Don’t know when to vaccinate | 66.1 | 12.8 | 14.0 | 7.1 | |
| No appropriate to take influenza vaccination | 56.8 | 24.4 | 12.2 | 6.5 | |
| Vaccination place is inconvenient | 69.3 | 12.8 | 9.5 | 8.3 | |
| Spend long time waiting for taking influenza vaccination | 62.5 | 20.5 | 11.3 | 5.7 | |
| Don't know where to vaccinate | 73.2 | 11.6 | 8.9 | 6.3 | |
| Influenza vaccination services are hard to make appointment | 67.9 | 17.6 | 9.8 | 4.8 | |
| Confidence | |||||
| Being worried about adverse reactions | 50.3 | 21.4 | 21.7 | 6.5 | |
| No influenza vaccination notification at workplace | 56.0 | 16.4 | 14.3 | 13.4 | |
| Influenza vaccine is not effective | 49.4 | 25.0 | 20.2 | 5.4 | |
| Having contraindications | 56.0 | 19.6 | 16.1 | 8.3 | |
| Pregnant or lactating | 67.0 | 14.6 | 10.1 | 8.3 | |
| Complacency | |||||
| Influenza will not cause severe illness | 31.3 | 25.3 | 32.1 | 11.3 | |
Of the 94.2% (2,945/3,127) of respondents who were willing to recommend influenza vaccines to others, no requirements at the government or workplace level for recommendation, fear of misinterpreting recommendation as having commercial interests, and potential adverse reactions were their primary concerns. Of the remaining respondents who were unwilling to recommend influenza vaccines, no requirements at the government or workplace level for recommendation and potential adverse reactions of influenza vaccines were their primary concerns (Table 2).
Table 2. Reasons for influenza vaccine recommendation among PHWs in China, September 2022.
| Variable | Total (n, %) | Willing to recommend (n, %) | |||
| Abbreviation: PHWs=public health workers. | |||||
| Worried about the misunderstanding of commercial interests by recipients | 1,440 (46.1) | 1,387 (47.1) | |||
| Worried about the adverse reactions of recipients | 1,313 (42.0) | 1,252 (42.5) | |||
| No recommendation on requirement by national authorities or at workplace | 1,312 (42.0) | 1,233 (41.9) | |||
| Pregnancy or have contraindications | 1,123 (35.9) | 1,068 (36.3) | |||
| Influenza won't cause severe illness and vaccination is unnecessary | 1,065 (34.1) | 1,004 (34.1) | |||
| Worried about the medical tangle caused by recommendation | 927 (29.6) | 886 (30.1) | |||
| Influenza vaccine is not effective | 861 (27.5) | 819 (27.8) | |||
| Due to self-unvaccinated and lack of influenza vaccine confidence | 596 (19.1) | 551 (18.7) | |||
| Influenza vaccination is inconvenient | 354 (11.3) | 336 (11.4) | |||
According to the results of univariate analysis, vaccine hesitancy was high among PHWs who did not receive an influenza vaccine in the 2021–2022 season (19.7%), who reported the payment method was inconvenient (15.7%), who were not concerned about the risk of influenza in the 2022–2023 season (14.7%), and who believed influenza vaccination was not important to health (65.6%) (Table 3).
Table 3. Univariate analysis and multivariable logistic regression analysis of influenza vaccine hesitancy among public health workers in China, September 2022 (ref: willing to vaccination).
| Variable | Total (n, %) | Vaccination willingness (n, %) |
Vaccine hesitancy
(n, %) |
Univariate analysis | Logistic regression analysis | |||
| χ 2 | P for chi-square test | OR (95% CI) | P-value | |||||
| Abbreviations: OR=adds ratio; CI=confidence interval. * In terms of GDP per capita, provincial-level administrative divisions (PLADs) are divided into three levels: low, middle and high. Low for Anhui, Qinghai, Jiangxi, Shanxi, Heilongjiang, Guangxi, Guizhou,Yunnan, Gansu; Middle for Chongqing, Shaanxi, Liaoning, Jilin, Hunan, Hainan, Henan, Sichuan, Hebei; High for Beijing, Shanghai, Tianjin, Jiangsu, Zhejiang, Fujian, Guangdong, Shandong, Inner Mongolia, Hubei. | ||||||||
| PLAD by GDP per capita* | ||||||||
| Low GDP area | 680 (21.7) | 588 (86.5) | 92 (13.5) | 8.81 | 0.012 | Ref | ||
| Middle GDP area | 1,413 (45.2) | 1,262 (89.3) | 151 (10.7) | 0.85 (0.61–1.19) | 0.346 | |||
| High GDP area | 1,034 (33.1) | 941 (91.0) | 93 (9.0) | 0.61 (0.43–0.88) | 0.008 | |||
| Type of workplace | ||||||||
| Community health service centers/Township health centers | 2,304 (73.7) | 2,043 (88.7) | 261 (11.3) | 3.10 | 0.078 | Ref | ||
| Center for Disease Control and Prevention | 823 (26.3) | 748 (90.9) | 75 (9.1) | 0.86 (0.60–1.22) | 0.392 | |||
| Professional title | ||||||||
| None | 347 (11.1) | 296 (85.3) | 51 (14.7) | 8.88 | 0.031 | Ref | ||
| Junior | 1,206 (38.6) | 1,070 (88.7) | 136 (11.3) | 1.21 (0.78–1.86) | 0.397 | |||
| Middle | 1,212 (38.8) | 1,095 (90.3) | 117 (9.7) | 1.19 (0.76–1.87) | 0.446 | |||
| Senior | 362 (11.6) | 330 (91.2) | 32 (8.8) | 1.25 (0.70–2.23) | 0.458 | |||
| Chronic diseases history (Except for simple hypertension) | ||||||||
| Yes | 153 (4.9) | 133 (86.9) | 20 (13.1) | 3.37 | 0.185 | Ref | ||
| No | 2,922 (93.4) | 2,615 (89.5) | 307 (10.5) | 0.51 (0.28–0.94) | 0.030 | |||
| Unclear | 52 (1.7) | 43 (82.7) | 9 (17.3) | 0.72 (0.26–2.03) | 0.538 | |||
| Influenza infection history since September 2021 | ||||||||
| Yes | 424 (13.6) | 400 (94.3) | 24 (5.7) | 13.26 | 0.001 | Ref | ||
| No | 2,176 (69.6) | 1,926 (88.5) | 250 (11.5) | 1.98 (1.21–3.24) | 0.006 | |||
| Unclear | 527 (16.9) | 465 (88.2) | 62 (11.8) | 1.98 (1.14–3.42) | 0.015 | |||
| Received influenza vaccine between September 2021 and April 2022 | ||||||||
| Yes | 1,643 (52.5) | 1,600 (97.4) | 43 (2.6) | 238.48 | <0.001 | Ref | <0.001 | |
| No | 1,484 (47.5) | 1,191 (80.3) | 293 (19.7) | 5.08 (3.54–7.29) | ||||
| On-site vaccination at workplace | ||||||||
| Yes | 2,650 (84.7) | 2,400 (90.6) | 250 (9.4) | 31.60 | <0.001 | Ref | ||
| No | 403 (12.9) | 332 (82.4) | 71 (17.6) | 1.50 (1.03–2.20) | 0.037 | |||
| Unclear | 74 (2.4) | 59 (79.7) | 15 (20.3) | 1.47 (0.71–3.07) | 0.303 | |||
| Ways of influenza vaccine payment | ||||||||
| Self-paid | 2,333 (74.6) | 2,047 (87.7) | 286 (12.3) | 43.49 | <0.001 | Ref | ||
| Free | 329 (10.5) | 313 (95.1) | 16 (4.9) | 0.60 (0.31–1.17) | 0.132 | |||
| Employer paid | 225 (7.2) | 214 (95.1) | 11 (4.9) | 0.89 (0.43–1.87) | 0.763 | |||
| Medical insurance | 208 (6.7) | 188 (90.4) | 20 (9.6) | 0.63 (0.36–1.11) | 0.111 | |||
| Unclear | 32 (1.0) | 29 (90.6) | 3 (9.4) | 0.39 (0.10–1.58) | 0.185 | |||
| Convenience of payment method | ||||||||
| Very convenient | 973 (31.1) | 910 (93.5) | 63 (6.5) | 43.49 | <0.001 | Ref | ||
| Moderately convenient | 1,295 (41.4) | 1,157 (89.3) | 138 (10.7) | 0.95 (0.66–1.39) | 0.807 | |||
| A little convenient | 558 (17.8) | 463 (83.0) | 95 (17.0) | 1.32 (0.86–2.01) | 0.202 | |||
| Not at all convenient | 301 (9.6) | 261 (86.7) | 40 (13.3) | 1.10 (0.65–1.86) | 0.717 | |||
| Perceived risk of influenza this season | ||||||||
| Very concerned | 132 (4.2) | 130 (98.5) | 2 (1.5) | 41.06 | <0.001 | Ref | ||
| Moderately concerned | 243 (7.8) | 230 (94.7) | 13 (5.3) | 2.53 (0.48–13.47) | 0.276 | |||
| A little concerned | 1,590 (50.8) | 1,440 (90.6) | 150 (9.4) | 3.11 (0.64–15.04) | 0.158 | |||
| Not at all concerned | 1,162 (37.2) | 991 (85.3) | 171 (14.7) | 5.26 (1.09–25.41) | 0.039 | |||
| Health influence of the influenza vaccine | ||||||||
| Very important | 1,531 (49.0) | 1,482 (96.8) | 49 (3.2) | 396.93 | <0.001 | Ref | ||
| Moderately important | 1,055 (33.7) | 932 (88.3) | 123 (11.7) | 2.50 (1.71–3.64) | <0.001 | |||
| A little important | 480 (15.4) | 356 (74.2) | 124 (25.8) | 4.21 (2.81–6.30) | <0.001 | |||
| Not at all important | 61 (2.0) | 21 (34.4) | 40 (65.6) | 21.32 (10.15–44.80) | <0.001 | |||
| Whether the trivalent or quadrivalent influenza vaccine affects willingness | ||||||||
| No | 1,137 (36.4) | 975 (85.8) | 162 (14.2) | 22.86 | <0.001 | Ref | ||
| Yes | 1,990 (63.6) | 1,816 (91.3) | 174 (8.7) | 0.97 (0.72–1.31) | 0.836 | |||
| Whether the inactivated or live-attenuated vaccine influences willingness | ||||||||
| No | 1,325 (42.4) | 1,139 (86.0) | 186 (14.0) | 25.99 | <0.001 | Ref | ||
| Yes | 1,802 (57.6) | 1,652 (91.7) | 150 (8.3) | 0.66 (0.49–0.89) | 0.006 | |||
| Workplace vaccination policy (free for all staff) | ||||||||
| Yes | 810 (25.9) | 766 (94.6) | 44 (5.4) | 34.16 | <0.001 | Ref | ||
| No | 2,038 (65.2) | 1,788 (87.7) | 250 (12.3) | 0.88 (0.55–1.41) | 0.602 | |||
| Unclear | 279 (8.9) | 237 (84.9) | 42 (15.1) | 0.70 (0.39–1.28) | 0.248 | |||
| Expectation from colleagues toward influenza vaccination this season | ||||||||
| No | 65 (2.1) | 44 (67.7) | 21 (32.3) | 213.15 | <0.001 | Ref | ||
| Yes | 1,715 (54.8) | 1,653 (96.4) | 62 (3.6) | 0.18 (0.09–0.37) | <0.001 | |||
| Unclear | 1,347 (43.1) | 1,094 (81.2) | 253 (18.8) | 0.58 (0.28–1.19) | 0.135 | |||
| Attitudes toward influenza vaccine this season at your workplace | ||||||||
| Required | 343 (11.0) | 328 (95.6) | 15 (4.4) | 94.5 | <0.001 | Ref | ||
| Encouraged | 1,038 (33.2) | 978 (94.2) | 60 (5.8) | 1.15 (0.59–2.25) | 0.678 | |||
| Neutrality | 1,442 (46.1) | 1,249 (86.6) | 193 (13.4) | 1.42 (0.73–2.74) | 0.301 | |||
| Unclear | 304 (9.7) | 236 (77.6) | 68 (22.4) | 1.57 (0.76–3.23) | 0.219 | |||
| How extensive do you consider your knowledge of the influenza vaccine | ||||||||
| Very confident | 1,361 (43.5) | 1,280 (94.0) | 81 (6.0) | 88.5 | <0.001 | Ref | ||
| Moderately confident | 1,181 (37.8) | 1,044 (88.4) | 137 (11.6) | 1.22 (0.87–1.72) | 0.252 | |||
| A little confident | 447 (14.3) | 354 (79.2) | 93 (20.8) | 1.45 (0.98–2.16) | 0.065 | |||
| Not at all confident | 138 (4.4) | 113 (81.9) | 25 (18.1) | 1.66 (0.91–3.03) | 0.101 | |||
Multivariable logistic regression analysis was used to assess factors associated with influenza vaccine hesitancy among PHWs. Those who had no influenza infection history (OR=1.98, 95% CI: 1.21–3.24), who did not receive an influenza vaccine between September 2021 and April 2022 (OR=5.08, 95% CI: 3.54–7.29), who could not receive on-site vaccination at workplace (OR=1.50, 95% CI: 1.03–2.20), who were not concerned about the risk of influenza this year (OR=5.26, 95% CI: 1.09–25.41), who believed the health influence of influenza vaccine is not important at all (OR=21.32, 95% CI: 10.15–44.80), a little important (OR=4.21, 95% CI: 2.81–6.30) and moderately important (OR=2.50, 95% CI: 1.71–3.64) were more likely to have hesitation toward influenza vaccination (Table 3).
DISCUSSION
The study found that 10.7% of PHWs were hesitant to get vaccinated against influenza during the COVID-19 pandemic. 52.5% of PHWs were vaccinated in the 2021–2022 season, which was higher than the 35.4% among respiratory care practitioners in the same season and 11.6% among HCWs in the 2018–2019 season (4-5). Although the influenza vaccination coverage in this survey is fairly optimistic, the small proportion of influenza vaccination hesitancy among PHWs still needs attention. The most cost-effective way to prevent influenza and its complications is annual vaccination, especially during the COVID-19 pandemic. As a high-risk population, PHWs vaccination against influenza not only reduces the harm from associated diseases and the use of medical resources, but also promotes health information communication and public confidence in influenza vaccination. The study elucidated primary concerns or no mandatory government or workplace recommendations for vaccination and vaccine safety among PHWs. In the interest of self-protection, potential adverse reactions to vaccines affect PHW willingness to recommend vaccines (9).
The study also suggested that complacency remains the biggest driver to influenza vaccine hesitancy and has the greatest impact on the willingness of PHWs to get vaccinated. Among the 336 hesitant PHWs, those without influenza infection and vaccination history were more prone to vaccine hesitancy, and those who did not worry about getting influenza in the current season or did not believe getting an influenza vaccination was important were at higher risk. Since the COVID-19 outbreak, public health interventions such as mask-wearing and social distancing have reduced influenza activity significantly. However, the measures also led to a decline in existing immunity and increased susceptibility to influenza. An increasing trend of influenza activity was observed in the northern hemisphere, highlighting the need for close monitorization and preparation for the co-circulation of influenza viruses and severe acute respiratory syndrome coronavirus 2 (10). PHWs need to be fully aware of the severity of influenza and the necessity for influenza vaccination as well as extensively understand the burden of influenza disease and prevention and control strategies during the COVID-19 pandemic. This helps reduce hesitancy toward influenza vaccines. Similar to other studies (4), the convenience of vaccination services is also an important factor for PHWs considering vaccination. Over the past year, many vaccination facilities have been used for COVID-19 vaccination, affecting the accessibility of influenza vaccines. The influenza vaccination payment did not affect the will of PHWs from this study. Generally, the first concern of PHWs with the medical background was the safety and effectiveness of vaccines. Influenza vaccine payment did not directly impact their vaccination decisions and intentions.
This study has some limitations. First, in the interest of quick, simple and feasible survey results, the online questionnaire was a quantitative survey without individual interviews. The results of the study were influenced by the cooperative attitude of the participants. Second, individual indicators vary considerably, and further expansion of the sample size is recommended. Third, specific differences could not be analyzed as the matrix questionnaire was used for PHWs’ intention to recommend influenza vaccine.
In conclusion, in the context of the potential co-circulation of influenza and COVID-19 in Winter 2022–2023, targeted interventions are needed among HCWs to improve influenza vaccination attitudes and behaviors, reduce the social hazards of influenza and protect the health of the population at large.
Conflicts of interest
No conflicts of interest.
Funding Statement
Supported by the China Association for Science and Technology (Project Number: 2021ZZKCB082026), and Bill & Melinda Gates Foundation (Project Number: INV-023808)
Contributor Information
Jiandong Zheng, Email: zhengjd@chinacdc.cn.
Luzhao Feng, Email: fengluzhao@cams.cn.
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