Abstract
Introduction
Health workers (HWs) set an example for vaccine recipients, convey vaccine benefits and risks and interface with patients at increased risk for complications in pandemic settings. We explored HWs’ acceptance of and recommendation for COVID-19 vaccine with and without previous receipt of seasonal influenza vaccine (SIV) in nine countries.
Methods
In 2023–2024, cross-sectional surveys among HW were conducted in Bangladesh, Cote d’Ivoire, Ghana, Laos, Lebanon, Morocco, Philippines, Thailand and Tunisia. Country researchers used a standard protocol and questionnaire to assess beliefs, perceptions and acceptance around SIV and COVID-19 vaccine and likelihood of recommending these vaccines to patients. Pooled findings were stratified by the presence or absence of a national HW SIV recommendation. Generalised mixed effects models were used to characterise the relationship between receipt of SIV and COVID-19 vaccine acceptance and recommendation, adjusting for WHO region, sex and duration of employment.
Results
Our analysis included 12 296 HWs from nine countries representing four WHO regions: African, Eastern Mediterranean, Southeast Asian and Western Pacific. Five countries had a national HW SIV recommendation (61% of HWs surveyed) prior to COVID-19 vaccine introduction. More than 90% of HWs reported completing the COVID-19 vaccination series, whereas intention to continue receiving annual COVID-19 vaccine was lower (61%). HWs who received SIV in the last season compared with those who did not were more likely to have received one or more COVID-19 booster doses (adjusted OR (aOR) 2.63, 95% CI 2.27 to 3.04) and to have recommended COVID-19 vaccine to patients (aOR 1.53, 95% CI 1.29 to 1.82).
Conclusions
Prior experience with SIV was associated with HW behaviour and recommendations regarding COVID-19 vaccination. Intention to continue receiving COVID-19 vaccines remains a challenge; ongoing training and education for vaccination staff could be beneficial. HWs play a critical role in the successful delivery of new and existing vaccines, particularly in a pandemic setting.
Keywords: Vaccines, COVID-19, Health Personnel, Global Health
WHAT IS ALREADY KNOWN ON THIS TOPIC
Health workers (HWs) play a vital role in promoting vaccine acceptance and adherence among priority populations, especially during pandemics.
While some studies have explored the influence of HWs’ vaccination behaviours, there are limited data on how prior experience with seasonal influenza vaccination affects HW acceptance and promotion of COVID-19 vaccines.
WHAT THIS STUDY ADDS
This multicountry study from nine diverse settings summarises HW knowledge and perspectives on seasonal influenza and COVID-19 vaccines and shows that HWs who received seasonal influenza vaccine were more likely to accept COVID-19 boosters and recommend COVID-19 vaccination to their patients.
HOW THIS STUDY MIGHT AFFECT RESEARCH, PRACTICE OR POLICY
Findings suggest that sustained investment in routine vaccination programmes for HWs, such as seasonal influenza vaccination, may strengthen acceptance of new vaccines and enhance pandemic preparedness efforts.
Introduction
The COVID-19 pandemic and associated rapid roll-out of COVID-19 vaccines represented a major undertaking for many immunisation programmes in low- and middle-income countries, in particular those with limited experience vaccinating populations outside routine childhood recipients.1 2 While the WHO’s Strategic Advisory Group of Experts, the body charged with advising WHO on global immunisation policies and strategies, recommends that health workers (HWs) are vaccinated annually with seasonal influenza vaccine (SIV), national influenza vaccination policies are not common in lower-income countries and the availability of influenza vaccines is often limited.3 4
HWs have an elevated risk of respiratory virus infections (ie, influenza, COVID-19) compared with the general public due to contact with sick patients and HWs may transmit these infections to their patients who are at higher risk of severe outcomes.5,7 For these reasons, HWs are a priority group for both influenza and COVID-19 vaccination programmes. HWs are also a key priority for vaccination in pandemic settings, as they are crucial for continuity of health services, can serve as an example of vaccine acceptance and may provide vaccination recommendations to patients. HWs who receive vaccines are more likely to recommend that vaccine to their patients and HW recommendation is strongly correlated with higher vaccine uptake among priority groups.8,10
During the 2009 influenza pandemic, countries with a national HW SIV recommendation were able to draw on existing systems for the rapid distribution and delivery of pandemic influenza vaccines.11 During the recent COVID-19 pandemic, widespread availability of COVID-19 vaccine in diverse settings globally afforded another opportunity to explore whether countries with existing HW SIV recommendations benefitted from greater acceptance and uptake of COVID-19 vaccines than countries without such programmes. We summarised data from surveys conducted in nine countries to describe, among HWs, uptake of COVID-19 vaccine, their likelihood to recommend COVID-19 vaccine and their knowledge, attitudes and practices associated with COVID-19 vaccination. Understanding the impact of previous HW SIV vaccination on the acceptability and uptake of COVID-19 vaccination in a variety of settings may inform planning for future HW vaccination efforts.
Methods
We conducted cross-sectional surveys about SIV and COVID-19 vaccine outcomes among HWs in nine purposively selected countries (Bangladesh, Cote d’Ivoire, Ghana, Laos, Lebanon, Morocco, Philippines, Thailand and Tunisia) from September 2023 to May 2024, with each country’s data collection period lasting 1–3 months. Consideration was given to WHO region and presence or absence of an HW SIV recommendation for selection of countries. Each country study team implemented the survey using a standard protocol and questionnaire developed by the central study team which outlined eligibility criteria, sample size parameters and recommended sampling approaches to promote consistency across countries. Questionnaires primarily followed the Health Belief Model,12 13 a framework describing constructs that predict health behaviour. Components of interest included perceived susceptibility, perceived severity, perceived benefits and perceived barriers. Specifically, questions evaluated perceptions of disease severity and susceptibility, knowledge related to COVID-19 vaccine, benefits of vaccination for HWs and their patients, barriers and motivators for vaccination and self-reported practices related to vaccination and vaccine recommendation. Minor adaptations were made to the questionnaire by country study teams as needed to reflect local contexts. Surveys were pilot tested in all countries to test readability, time required for completion and clarity and translated into local languages, as needed. Surveys were administered in person by trained data collectors using electronic data collection tools such as Open Data Kit software. Two countries, Morocco and Lebanon, elected to conduct the survey as an online questionnaire due to response preferences of survey recipients or logistical feasibility.
Country implementation teams invited HWs with direct patient contact to participate in the survey. Proposed sample size and sampling methods, including random, stratified and purposive selection of health facilities, were finalised by implementation teams with the intention to create a national-level sample that would ensure diverse SIV and COVID-19 immunisation perspectives were captured (online supplemental table 1). Each country team, with the support of the Ministry of Health, determined the geographical scope, levels of health facilities, inclusion of private facilities and specific occupations of HWs included in the survey to ensure that the survey reflected local contexts and would inform the ministry of health around planning of immunisation programmes.
Individual-level data from all surveys were translated to English and pooled. Variables were aligned by matching standard questions and answer choices. Country income status was assigned using World Bank income group classification14 during 2024. The multicountry descriptive analysis focused on countries with and without national HW SIV recommendations, defined by a country reporting ‘an influenza vaccination recommendation for health and care workers’ via the WHO/UNICEF Joint Reporting Form (JRF)15 during the year COVID-19 vaccination began (2021). Morocco did not report this indicator to JRF in 2021, but the presence of HW SIV recommendation was confirmed by the country survey team. A key survey variable used in multivariable analysis was receipt of SIV during the last season, which was independent of country. HWs in countries without a national SIV recommendation may have received SIV through private clinics and responded as such to the questionnaire.
We described the survey population and summarised data related to HW acceptance and recommendation of COVID-19 vaccine. Proportions for key variables were calculated and stratified by the presence of an SIV programme. Bivariate analyses were conducted to characterise trends for three outcomes: completion of COVID-19 vaccine primary series, receipt of one or more booster doses and recommendation of COVID-19 vaccine during initial vaccine rollout. Questions about knowledge and perceptions about COVID-19 illness and vaccination were measured using a 5-point Likert scale and frequencies were analysed. During bivariate analysis, the perceived risk, benefit and safety variables for COVID-19 vaccine were dichotomised. Positive responses (‘agree’ or ‘strongly agree’ and ‘safe’ or ‘very safe’) were assigned a code of 1, while negative responses (‘disagree’ or ‘strongly disagree’ and ‘unsafe’ or ‘very unsafe’) were assigned 0. Responses of ‘Don’t know’ were assigned a code of 0 and missing or ‘refused to answer’ responses were excluded. This approach ensured that informative responses, including uncertainty, were factored into the findings.
We conducted multivariable logistic regression using a generalised mixed effects model to characterise the relationship between respondents reporting receipt of SIV in the last season and COVID-19 vaccine uptake and recommendation. In addition, variables included in the model were selected a priori and included WHO region, sex, duration of employment and occupation (cadre of HW). ORs were adjusted for cluster effect at the health facility level, and for two countries that implemented online-only surveys, the lowest geographical region available was used. Data were pooled and analysed in R statistical software with mixed-effects modelling conducted using the lme4 package.16 17
Patient and public involvement
It was not appropriate or possible to involve patients in the design, conduct, reporting or dissemination of this research, as the survey respondents were HWs only.
Results
Study population
Our analysis included pooled data from 12 296 HWs from nine countries, representing four of the six WHO regions: African (n=2628, 21%), Eastern Mediterranean (n=3622, 29%), Southeast Asian (n=4192, 34%) and Western Pacific (n=1854, 15%) (table 1). 82% of survey participants were from lower middle-income countries (n=10 116) and 18% from one upper middle-income country (n=2180), which had a national HW SIV recommendation. Five countries had a national HW SIV recommendation when COVID-19 vaccine was introduced (n=7504 HWs) and four had no such recommendations (n=4792). Overall, nearly two-thirds (n=7815, 64%) of the sample were female HW and 60% (n=7377) were less than 40 years of age. Respondents included medical doctors (n=4742, 39%), nurses (n=4224, 34%), midwives (n=1001, 8%) and other healthcare personnel (n=2327, 19%) (table 2).
Table 1. Characteristics of countries included in the analysis and overall sample.
| Country | n (%) | WHO region | World Bank income group | National HW SIV recommendation in 2021* |
|---|---|---|---|---|
| Bangladesh | 2012 (16) | Southeast Asia | Lower middle | No |
| Cote d’Ivoire | 1460 (12) | Africa | Lower middle | Yes |
| Ghana | 1168 (10) | Africa | Lower middle | No |
| Laos | 1261 (10) | Western Pacific | Lower middle | Yes |
| Lebanon | 1019 (8) | Eastern Mediterranean | Lower middle | No |
| Morocco | 1697 (14) | Eastern Mediterranean | Lower middle | Yes |
| Philippines | 593 (5) | Western Pacific | Lower middle | No |
| Thailand | 2180 (18) | Southeast Asia | Upper middle | Yes |
| Tunisia | 906 (7) | Eastern Mediterranean | Lower middle | Yes |
| Total | 12 296 (100) |
Defined by a country reporting an influenza vaccination recommendation for health and care workers via the WHO/UNICEF Joint Reporting Form. Morocco confirmed this designation to the author team.
HW, health worker; SIV, seasonal influenza vaccine.
Table 2. Description of HWs, among nine countries that have or do not have a national HW seasonal influenza vaccine recommendation.
| Characteristic | Overall, N=12 296* | Presence of a national HW SIV recommendation | |
|---|---|---|---|
| No, N=4792* | Yes, N=7504* | ||
| Geographical region | |||
| African region | 2628 (21) | 1168 (24) | 1460 (19) |
| Eastern Mediterranean region | 3622 (29) | 1019 (21) | 2603 (35) |
| Southeast Asian region | 4192 (34) | 2012 (42) | 2180 (29) |
| Western Pacific region | 1854 (15) | 593 (12) | 1261 (17) |
| World Bank income group | |||
| Lower middle income | 10 116 (82) | 4792 (100) | 5324 (71) |
| Upper middle income | 2180 (18) | 0 (0) | 2180 (29) |
| Sex | |||
| Male | 4440 (36) | 2472 (52) | 1968 (26) |
| Female | 7815 (64) | 2295 (48) | 5520 (74) |
| Missing | 41 | 25 | 16 |
| Age | |||
| 18–24 | 477 (4) | 57 (1) | 420 (6) |
| 25–29 | 1874 (15) | 827 (17) | 1047 (14) |
| 30–34 | 2576 (21) | 1275 (27) | 1301 (17) |
| 35–39 | 2450 (20) | 973 (20) | 1477 (20) |
| 40–49 | 2711 (22) | 867 (18) | 1844 (25) |
| 50–59 | 1754 (14) | 511 (11) | 1243 (17) |
| 60+ | 432 (4) | 272 (6) | 160 (2) |
| Missing | 22 | 10 | 12 |
| Years worked in healthcare | |||
| Less than 1 year | 181 (1) | 80 (2) | 101 (1) |
| 1–4 years | 2723 (22) | 1165 (25) | 1558 (21) |
| 5–9 years | 2843 (23) | 1121 (24) | 1722 (23) |
| 10–14 years | 2387 (20) | 975 (21) | 1412 (19) |
| 15–19 years | 1169 (10) | 443 (9) | 726 (10) |
| 20–24 years | 1058 (9) | 367 (8) | 691 (9) |
| 25–29 years | 741 (6) | 208 (4) | 533 (7) |
| 30+ years | 1061 (9) | 336 (7) | 725 (10) |
| Missing | 133 | 97 | 36 |
| Occupation | |||
| Medical doctors | 4742 (39) | 3223 (67) | 1519 (20) |
| Nurses | 4224 (34) | 1067 (22) | 3157 (42) |
| Midwives | 1001 (8) | 252 (5) | 749 (10) |
| Other healthcare personnel | 2327 (19) | 250 (5) | 2077 (28) |
| Missing | 2 | 0 | 2 |
n (%).
HW, health worker; SIV, seasonal influenza vaccine.
Reported vaccination practices and intentions
Overall, only 42% of HWs (n=5113) indicated they received SIV in the last season (55%, n=4083 of HWs in countries with a national HW SIV recommendation and 22% (n=1030) in countries with no national HW SIV recommendation) (table 3). 96% (n=11 736) of HWs in the sample reported receiving any dose of COVID-19 vaccine with 94% (n=11 068) indicating that they had completed the series. When stratifying by presence of national HW SIV recommendation, 98% (n=4686) of HWs in countries with no national HW SIV recommendation and 94% (n=7050) in countries with a national HW SIV recommendation reported having received COVID-19 vaccines since they were introduced in the country. Overall, 80% (n=9074) of HWs received one or more COVID-19 boosters, including 81% (n=3677) in countries with no national HW SIV recommendation and 80% (n=5397) in countries with a national HW SIV recommendation. However, a greater proportion (81%, n=3526) of HWs in countries with no national HW SIV recommendation intended to continue to receive additional COVID-19 vaccine boosters than in countries with a national HW SIV recommendation (55%, n=3963). Overall, among countries without and with national HW SIV recommendation, 72% (n=3431) and 54% (4028) indicated they would receive annual COVID-19 boosters, respectively. Although most (91%, n=11 203) of HWs indicated they recommended COVID-19 vaccine during the pandemic, 69% (n=7122) continue to recommend COVID-19 vaccine at the time of the survey and 73% (n=8889) of HWs indicated that they would recommend it annually (table 3).
Table 3. Reported COVID-19 vaccine practices among HWs, by whether countries have or do not have a national HW seasonal influenza vaccine recommendation (n=9 countries).
| Characteristic | Overall, N=12 296* | Presence of a national HW SIV recommendation | |
|---|---|---|---|
| No, N=4792* | Yes, N=7504* | ||
| Received any dose of COVID-19 since vaccines were introduced in country | |||
| Yes | 11 736 (96) | 4686 (98) | 7050 (94) |
| No | 465 (3.8) | 81 (1.7) | 384 (5.1) |
| Do not know | 69 (0.6) | 11 (0.2) | 58 (0.8) |
| Missing | 26 | 14 | 12 |
| Received complete series of COVID-19 vaccine | |||
| Yes | 11 086 (94) | 4534 (97) | 6552 (92) |
| No | 647 (5.5) | 138 (2.9) | 509 (7.1) |
| Do not know | 86 (0.7) | 9 (0.2) | 77 (1.1) |
| Missing | 477 | 111 | 366 |
| Received one or more COVID-19 booster doses | |||
| Yes | 9074 (80) | 3677 (81) | 5397 (80) |
| No | 2069 (18) | 817 (18) | 1252 (19) |
| Do not know | 149 (1.3) | 35 (0.8) | 114 (1.7) |
| Missing | 1004 | 263 | 741 |
| Would continue to receive COVID-19 vaccination, if recommended | |||
| Yes | 7489 (65) | 3526 (81) | 3963 (55) |
| No | 2907 (25) | 583 (13) | 2324 (33) |
| Do not know | 1115 (9.7) | 258 (5.9) | 857 (12) |
| Missing | 785 | 425 | 360 |
| Would receive COVID-19 vaccine annually, if recommended | |||
| Yes | 7459 (61) | 3431 (72) | 4028 (54) |
| No | 3336 (27) | 842 (18) | 2494 (33) |
| Do not know | 1471 (12) | 499 (10) | 972 (13) |
| Missing | 30 | 20 | 10 |
| Received SIV last season | |||
| Yes | 5113 (42) | 1030 (22) | 4083 (55) |
| No | 6780 (55) | 3609 (76) | 3171 (42) |
| Do not know | 346 (2.8) | 123 (2.6) | 223 (3.0) |
| Not eligible for vaccination | 9 (<0.1) | 0 (0) | 9 (0.1) |
| Missing | 48 | 30 | 18 |
| Recommended COVID-19 vaccine during pandemic† | |||
| Yes | 11 203 (91) | 4621 (97) | 6582 (88) |
| No | 1006 (8.2) | 138 (2.9) | 868 (12) |
| Do not know | 40 (0.3) | 5 (0.1) | 35 (0.5) |
| Missing | 47 | 28 | 19 |
| Continues to recommend COVID-19 vaccine | |||
| Yes | 7122 (69) | 3439 (72) | 3683 (66) |
| No | 3190 (31) | 1295 (27) | 1895 (34) |
| Do not know | 15 (0.1) | 15 (0.3) | 0 (0) |
| Missing | 1969 | 43 | 1926 |
| Would recommend COVID-19 vaccine annually | |||
| Yes | 8889 (73) | 3814 (80) | 5075 (68) |
| No | 1672 (14) | 414 (8.7) | 1258 (17) |
| Do not know | 1685 (14) | 524 (11) | 1161 (15) |
| Missing | 50 | 40 | 10 |
n (%).
Defined as having ever recommended COVID-19 vaccine to a patient during the pandemic; frequency not specified.
HW, health worker; SIV, seasonal influenza vaccine.
Health worker experience, knowledge and beliefs on COVID-19 vaccine
62% of HWs indicated they had ever made a clinical or laboratory-confirmed diagnosis of COVID-19 in a patient (69%, n=3303 in countries without a national HW SIV recommendation and 57%, n=4271 in countries with such a recommendation). Nearly half (47%, n=5730) of HWs reported that they had treated a patient that developed a life-threatening complication or required hospitalisation because of COVID-19. 22% of all HWs (26%, n=1200, in countries without a national HW SIV recommendation and 19%, n=1425 in countries with a national HW SIV recommendation) agreed with the statement that COVID-19 vaccine can protect against influenza. The top three patient groups that HWs would recommend prioritising for COVID-19 vaccination at the time of the survey were older adults (40%, n=2991), HWs (14%, n=1086) and people living with HIV/AIDS (13%, n=986) (online supplemental table 2).
Most respondents (80%, n=6035) of HWs in countries with a national HW SIV recommendation, and nearly all (97%, n=4647) of HWs in countries without a national HW SIV recommendation agreed or strongly agreed that COVID-19 can cause serious illness requiring hospitalisation, long-term care or death among unvaccinated HWs (illustrated by the green bars in online supplemental figure 1). Similarly, most respondents in countries with a national HW SIV recommendation (79%, n=5937) and nearly all respondents in countries without a national HW SIV recommendation (96%, n=4593) agreed or strongly agreed with the statement ‘getting the COVID-19 vaccine can greatly reduce the chances of HWs becoming severely ill’. While respondents also believed that COVID-19 vaccines are safe or very safe for various groups, more respondents in countries with a national HW SIV recommendation than those without believed that COVID-19 vaccines are unsafe or very unsafe for certain groups, particularly pregnant women (25%, n=1871 vs 8%, n=414) and children and adolescents (25%, n=1915 vs 5%, n=224). Respondent beliefs on COVID-19 disease severity, vaccine effectiveness and vaccine safety for different priority populations can be seen in online supplemental figure 1.
Factors associated with COVID-19 vaccine uptake and recommendation
In unadjusted bivariate analysis, female HWs were less likely than males to have completed the primary series (OR 0.75; 95% CI 0.63 to 0.89), received one or more booster doses (OR 0.78; 95% CI 0.70 to 0.86) or recommended COVID-19 vaccine (OR 0.55; 95% CI 0.47 to 0.64) (figure 1). HWs who reported receiving SIV in the last season were more likely to have completed the COVID-19 primary series (OR 1.45; 95% CI 1.23 to 1.72), received one or more booster doses (OR 3.09; 95% CI 2.77 to 3.46) or recommended COVID-19 vaccination (OR 1.40; 95% CI 1.22 to 1.60) than those who did not report receiving SIV in the last season (figure 1).
Figure 1. Factors associated with completion of COVID-19 vaccine series, receipt of one or more booster and recommendation of COVID-19 vaccine among HW (unadjusted ORs in generalised mixed effects models). Red diamonds indicate p value < 0.05. HW, health worker.
HWs who believed COVID-19 can cause serious illness requiring hospitalisation, long-term care or death in unvaccinated HWs were more likely to have completed the COVID-19 primary series (OR 1.71; 95% CI 1.34 to 2.17), received one or more booster doses (OR 2.88; 95% CI 2.48 to 3.33) or recommended COVID-19 vaccine (OR 2.62; 95% CI 2.17 to 3.14) than those who did not believe that COVID-19 can cause serious illness. HWs who believed that getting the COVID-19 vaccine can greatly reduce the chances of HWs becoming severely ill were at least three times more likely to have completed the primary series (OR 3.12; 95% CI 2.55 to 3.81), received one or more booster doses (OR 3.79; 95% CI 3.30 to 4.35) or recommended COVID-19 vaccine (OR 4.79; 95% CI 4.08 to 5.61) than those who did not believe the COVID-19 vaccine was effective. HWs who believed the COVID-19 vaccine was safe were more than two times as likely to have completed the primary series (OR 2.81; 95% CI 2.32 to 3.38), received one or more booster doses (OR 2.79; 95% CI 2.46 to 3.16) or recommended COVID-19 vaccine (OR 3.84; 95% CI 3.30 to 4.46), figure 1. In the multivariable models, HWs reporting receipt of SIV in the last season were more likely to have received one or more booster doses (adjusted OR (aOR) 2.62, 95% CI 2.26 to 3.04) and recommended COVID-19 vaccine to patients (aOR 1.53, 95% CI 1.29 to 1.82) than HWs reporting they did not receive SIV in the last season. HWs that reported receiving SIV in the last season were as likely to have completed the primary COVID-19 vaccine primary series than those who did not (aOR 1.17, 95% CI 0.96 to 1.42) (table 4).
Table 4. Adjusted ORs for HWs’ COVID-19 vaccine outcomes among respondents who reported receipt of SIV in the last season in generalised mixed effects models*†.
| Completed COVID-19 vaccine series | Received one or more COVID-19 boosters | Recommended COVID-19 vaccine | |||||||
|---|---|---|---|---|---|---|---|---|---|
| Characteristic | aOR ‡ | 95% CI‡ | P value | aOR ‡ | 95% CI‡ | P value | aOR ‡ | 95% CI‡ | P value |
| Received SIV last season | 1.17 | 0.96 to 1.42 | 0.13 | 2.62 | 2.26 to 3.04 | <0.001 | 1.53 | 1.29 to 1.82 | <0.001 |
| WHO region | |||||||||
| African region | — | — | — | — | — | — | |||
| Eastern Mediterranean region | 0.38 | 0.28 to 0.51 | <0.001 | 0.24 | 0.18 to 0.31 | <0.001 | 0.20 | 0.15 to 0.29 | <0.001 |
| Southeast Asia region | 1.69 | 1.12 to 2.55 | 0.013 | 2.60 | 1.76 to 3.85 | <0.001 | 0.70 | 0.45 to 1.09 | 0.11 |
| Western Pacific region | 3.68 | 2.22 to 6.11 | <0.001 | 4.17 | 2.82 to 6.16 | <0.001 | 4.33 | 2.36 to 7.92 | <0.001 |
| Duration of employment | |||||||||
| Less than 1 year | — | — | — | — | — | — | |||
| 1–4 years | 2.44 | 1.28 to 4.66 | 0.007 | 1.32 | 0.79 to 2.21 | 0.3 | 4.27 | 2.64 to 6.91 | <0.001 |
| 5–9 years | 2.85 | 1.49 to 5.46 | 0.002 | 1.40 | 0.84 to 2.33 | 0.2 | 5.22 | 3.20 to 8.49 | <0.001 |
| 10–14 years | 2.61 | 1.36 to 5.02 | 0.004 | 1.41 | 0.84 to 2.36 | 0.2 | 5.12 | 3.12 to 8.39 | <0.001 |
| 15–19 years | 3.24 | 1.63 to 6.45 | <0.001 | 1.62 | 0.95 to 2.77 | 0.074 | 4.14 | 2.47 to 6.93 | <0.001 |
| 20–24 years | 4.62 | 2.27 to 9.43 | <0.001 | 1.90 | 1.11 to 3.26 | 0.020 | 6.62 | 3.85 to 11.4 | <0.001 |
| 25–29 years | 4.71 | 2.22 to 9.99 | <0.001 | 2.17 | 1.23 to 3.83 | 0.007 | 6.25 | 3.55 to 11.0 | <0.001 |
| 30+ years | 4.25 | 2.07 to 8.72 | <0.001 | 2.02 | 1.16 to 3.49 | 0.012 | 6.36 | 3.67 to 11.0 | <0.001 |
| Occupation | |||||||||
| Medical doctors | — | — | — | — | — | — | |||
| Nurses | 0.56 | 0.43 to 0.73 | <0.001 | 0.66 | 0.54 to 0.80 | <0.001 | 0.45 | 0.34 to 0.59 | <0.001 |
| Midwives | 0.69 | 0.47 to 1.01 | 0.055 | 0.86 | 0.66 to 1.12 | 0.3 | 0.42 | 0.29 to 0.60 | <0.001 |
| Other healthcare personnel | 0.43 | 0.32 to 0.58 | <0.001 | 0.65 | 0.52 to 0.82 | <0.001 | 0.17 | 0.13 to 0.22 | <0.001 |
| Sex | |||||||||
| Male | — | — | — | — | — | — | |||
| Female | 0.87 | 0.72 to 1.06 | 0.2 | 0.73 | 0.64 to 0.83 | <0.001 | 0.71 | 0.59 to 0.84 | <0.001 |
Generalised mixed effects model adjusted for WHO region, duration of employment, occupation, sex and cluster effect at the health facility level.
Observations excluded with missing values for any outcome or covariate.
aOR=adjusted OR, CI=Confidence Interval
HW, health worker; SIV, seasonal influenza vaccine.
Discussion
Findings from these surveys showed that more HWs in countries with national HW SIV recommendations reported receiving SIV than those without national HW SIV recommendations. A review of HW vaccination programmes in low, middle and upper middle-income countries found support and encouragement from institutional leaders and use of existing immunisation infrastructure to be key facilitators in the implementation of HW vaccination programmes.18 At an individual level, studies have found that a desire to protect oneself and others and previous receipt of influenza vaccine was a determinant of receipt of additional influenza vaccine uptake among HWs.19 20 Our analysis found that previous receipt of influenza vaccine among individual HWs was associated with receipt of one or more COVID-19 vaccine booster doses and recommendation of COVID-19 vaccine to patients.
HWs are crucial to maintaining continuity of services during a pandemic and their behaviour and recommendation can strongly influence vaccine uptake.1021,24 Previous studies have shown that SIV history is a strong predictor of COVID-19 vaccine and pandemic influenza vaccine acceptance.2025,27 This is the first study to assess the relationship between HWs’ SIV and COVID-19 vaccination behaviours in multiple countries and across WHO regions. It is possible that normalisation of vaccination through SIV vaccination in an occupational setting in these countries may have led to greater acceptance of COVID-19 vaccines, particularly for the receipt of repeated vaccine doses.
Overall, uptake of COVID-19 vaccine among HWs in the nine countries included in the study was high, a critical component of effective pandemic response. The WHO designated HWs as the first priority group in the initial roadmap for prioritising uses of COVID-19 vaccines for stage I scenario, in which very limited vaccine supply is available.28 HWs were the most frequently prioritised group in official published plans for initial COVID-19 vaccination rollout, with many countries implementing mandates according to occupation.29 In the Western Pacific region specifically, high overall coverage of COVID-19 vaccines, comparatively strong trust in health systems, well-established immunisation programmes and prioritisation of HW in COVID-19 vaccination efforts have been well documented.30,33 These factors likely contributed to geographical associations with COVID-19 outcomes in our study. We found that intent to continue to receive COVID-19 booster doses among HWs in our study declined as national governments shifted from acute pandemic response to longer-term management and control; this decline is mirrored in the general population.34
HWs in our survey agreed that COVID-19 can cause serious illness and that vaccines are safe and effective for various groups. Negative perceptions around COVID-19 vaccine safety and effectiveness were somewhat more common among HWs in countries with national HW SIV recommendations. In countries with a national HW SIV recommendation, HWs’ exposure to SIV and experiences with hesitancy may foment more of an array of attitudes and beliefs related to respiratory virus vaccines than in countries where populations are naïve to or inexperienced with SIV. In Finland, researchers found that vaccine attitude and belief patterns were similar between COVID-19 and SIV hesitant groups, but greater variety in hesitancy was evident around COVID-19 vaccines, potentially related to the large societal impact and extensive discourse around the COVID-19 pandemic.35 In a pooled analysis of 12 countries’ survey data on SIV knowledge, attitudes, perceptions and practices, HWs in countries without a national HW SIV recommendation were willing to pay more for SIV than those with a national HW SIV recommendation.10 HWs in countries with a national influenza recommendation may have been more frequently exposed to mis-information and dis-information about SIV, and more varying perceptions around vaccines in general, giving them more information on which to form an opinion around vaccines than those with less exposure to the concept. This finding highlights the importance of implementing continual efforts to combat vaccine hesitancy, even among HWs. While COVID-19 vaccine uptake among HWs was high in our study, vaccine hesitancy remains widespread globally. Culturally sensitive and population-specific interventions could be helpful to address the problem.36
The COVID-19 vaccine rollout challenged many countries to expand their immunisation programmes to populations beyond those traditionally reached with childhood vaccination programmes. Though nearly all countries introduced COVID-19 vaccines in a short period of time, there was a range of programme experiences. A 2024 analysis of all WHO Member States responding to the WHO JRF on COVID-19 vaccination found that having an adult SIV programme was significantly correlated with higher capacity to introduce COVID-19 vaccine and higher COVID-19 vaccine primary series coverage among the total population.37 Similarly, countries with mature HW SIV programs achieved higher and faster COVID-19 vaccine coverage, as demonstrated in a recent analysis incorporating both population-level coverage data and stakeholder interview data.38 Additionally, a qualitative analysis in 11 countries corroborated that the ability to adapt existing influenza and HW vaccination systems was valuable to COVID-19 vaccine response efforts.39 Cross-cutting factors leveraged for COVID-19 vaccine roll-out included occupational health policies, human resources, vaccine delivery platforms and communication channels.39
In our survey, more than 20% of HWs believed that COVID-19 vaccine can protect against influenza, which was unexpected. As COVID-19 and influenza are respiratory diseases with some overlapping symptoms, there is a need to emphasise the distinction between the diseases and the lack of cross-protection of COVID-19 and SIV vaccines during training of HWs, as HWs are a trusted source of information for the general population.40 41 There is a need for tailored communication and education campaigns for HWs around adult respiratory virus vaccines, particularly as new vaccines such as those which help protect against respiratory syncytial virus are rolled out to certain groups,42 to increase knowledge and improve confidence in communicating with patients about vaccines. This might include regular refresher training and continuing education sessions, dedicated online learning platforms to access up-to-date resources and dissemination of comprehensive educational materials and job aids.
This study has several limitations. First, there was wide variation in how COVID-19 vaccine was introduced globally, and policies, mandates and recommendations varied by country and evolved rapidly over time.43 There was also variation in the timeline for COVID-19 vaccine roll-out in the countries in the study with variable and sometimes intermittent vaccine availability. Because survey sampling approaches varied slightly across the nine countries included in the analysis, individual-level data from country surveys were pooled generally and sampling weights were not applied. In some countries, questionnaires were translated into local languages, which may have introduced variation in how questions were interpreted. However, back translation and pilot testing were used to mitigate this risk. Survey responses related to vaccine receipt relied on recall and were not verified by documented records; thus, surveys may have been susceptible to recall or response bias with respondents providing survey responses they perceive to be favourable to the interviewer. However, the potential for bias was mitigated by the training that was given to study interviewers and the fact that the survey was anonymous and conducted confidentially. Given the methodological differences and context-specific factors across countries, the generalisability of the findings to other settings or populations may be limited. Analysis of future intent to receive or recommend COVID-19 vaccines was considered but not included, as intent measures were not part of the study’s focus on current behaviours. Finally, country-specific analyses were conducted by implementation teams to inform local strategies but are not presented here, as comparative results were beyond the scope of this multicountry study.
Conclusions
Our findings highlight the success of reaching HWs, a key priority group, with COVID-19 vaccines during the pandemic period. There was strong agreement about the severity of COVID-19 disease and the overall safety and effectiveness of COVID-19 vaccine. Among HWs, previous receipt of SIV vaccine was associated with COVID-19 vaccine uptake, particularly for booster doses. Seasonal and routine vaccination programmes provide an opportunity to normalise vaccination for all populations and enhance sensitisation, uptake and preparedness across the life course. Though demand for vaccines, especially adult vaccines, evolves and is complex, HWs are a crucial population to reach with new vaccines in a pandemic setting.
Supplementary material
Acknowledgements
We would like to thank the Ministries of Health, interviewers and HWs in countries participating in the survey; Cassidy Rothfeder, Lindsay Saber and Cara Tupps for their assistance with data cleaning and merging; Vic Viguilla for his valuable inputs on questionnaire development; Tat Yau for his advice on data management and statistical analysis; and Amanda Edwards and Dominique Richardson for their coordination, tracking and funding administration.
The findings and conclusions in this article are those of the authors and do not necessarily represent the official position of the funding agencies.
Footnotes
Funding: This work was supported by funding from the Centers for Disease Control and Prevention (CDC) through the Task Force for Global Health (TFGH) under Cooperative Agreement 5 NU51IP0001916-02-00.
Provenance and peer review: Not commissioned; externally peer reviewed.
Handling editor: Elisa Maria Maffioli
Patient consent for publication: Not applicable.
Ethics approval: This activity was reviewed by CDC, deemed not research and was conducted consistent with applicable federal law and CDC policy (45 C.F.R. part 46, 21 C.F.R. part 56; 42 U.S.C. §241(d); 5 U.S.C. §552a; 44 U.S.C. §3501 et seq.) In each country, all relevant ethical review boards similarly determined the activity to be non-research and implementing partners obtained any further approvals required by local regulations. All participants provided oral or written informed consent to participate in the surveys.
Patient and public involvement: Patients and/or the public were not involved in the design, or conduct, or reporting, or dissemination plans of this research.
Data availability statement
Data are available upon reasonable request. All data relevant to the study are included in the article or uploaded as supplementary information.
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Associated Data
This section collects any data citations, data availability statements, or supplementary materials included in this article.
Supplementary Materials
Data Availability Statement
Data are available upon reasonable request. All data relevant to the study are included in the article or uploaded as supplementary information.