Abdullah Al-Mikhlafy1, Mahdi Al Karawani1, Rashad Abdul-Ghani2,3, Ibrahim Alsubol4, Asmaa Al-Awadi4, Mogahid Nassar5, Mohammed Alshehab6,7, Adel Almutawakel1, Adeeb Salah8, Ahlam Abdultwab6,9
1Department of Community Medicine, Faculty of Medicine and Health Sciences, University of Science and Technology, Sana’a, Yemen. 2Department of Medical Parasitology, Faculty of Medicine and Health Sciences, Sana’a University, Sana’a, Yemen (Correspondence: R. Abdul-Ghani:
Abstract
Background: Acceptability of COVID-19 vaccines by the general population is affected by their acceptability by healthcare workers (HCWs).
Aims: To assess COVD-19 vaccine acceptability and hesitancy among HCWs in Sana’a City, Yemen.
Methods: We conducted a multicentre cross-sectional study among 391 HCWs in Sana’a City from January to March 2022. A self-administered questionnaire was used to collect data about demographics, profession, qualifications, and experience of HCWs, as well as COVID-19 vaccine acceptability and the reasons for hesitancy. Univariate and multivariable logistic regression analysed the association between independent variables and vaccine hesitancy at P < 0.05.
Results: COVID-19 vaccine acceptability was observed among 194 of 391 (49.6%) HCWs. The most frequent reasons for vaccine hesitancy were fear of adverse effects (77.7%), concerns about unknown future effects (73.1%), and safety of novel vaccines (69.5%). Female gender and working in the public sector were independent predictors of vaccine hesitancy among HCWs.
Conclusion: Around half of the HCWs in Sana’a City accepted COVID-19 vaccination. The majority of vaccine-hesitant HCWs have safety concerns, perceive that vaccination is unnecessary and have doubts about vaccine effectiveness and emerging virus variants. Female gender and working in the public sector are independent predictors of vaccine hesitancy.
Keywords: COVID-19 vaccine, vaccine acceptability, vaccine hesitancy, healthcare workers, Yemen
Citation: Al-Mikhlafy AA, Al Karawani M, Abdul-Ghani R, Alsubol I, Al-Awadi AAH, Nassar MY et al. COVID-19 vaccine acceptability and hesitancy among healthcare workers in Sana’a City, Yemen. East Mediterr Health J. 2023;29(x):xxx-xxx https://doi.org/10.26719/emhj/23.109 Received: 25/12/2022 Accepted: 28/04/2023
Copyright: © Authors; licensee World Health Organization. EMHJ is an open access journal. All papers published in EMHJ are available under the Creative Commons Attribution Non-Commercial ShareAlike 3.0 IGO licence (CC BY-NC-SA 3.0 IGO; https://creativecommons.org/licenses/by-nc-sa/3.0/igo).
Introduction
Since its emergence in China in December 2019 (1), COVID-19 has spread globally and become a pandemic with serious health and economic threats. The World Health Organization (WHO) declared the outbreak a Public Health Emergency of International Concern on 30 January 2020 and characterized it as a pandemic on 11 March 2020 (2). With the lack of specific treatment, pandemic containment efforts are directed towards preventive measures, with vaccination being a cost-effective measure to prevent infection and achieve herd immunity. To achieve vaccine equity as a key principle to global health security, the COVID-19 Global Vaccine Access (COVAX) initiative was launched to expedite vaccine development and manufacture and ensure equitable access for all countries (3).
On 10 April 2020,Yemen confirmed its first case of COVID-19 in a 60-year-old man working at Ash-Shihr Port in Hadhramout Governorate (4). Later, two healthcare workers (HCWs) were confirmed with COVID-19 in Sana’a City (5). Ongoing conflicts, humanitarian crises, complex emergencies, and continuous influx of expatriates put the country at potential risk. The fragile health system and ill-equipped facilities were not well prepared to cope with epidemics (6). As of 16 December 2022, 11 945 confirmed cases had been reported, with 2159 deaths (7). However, the actual burden may have been higher because of problems with confirmation and reporting.
Vaccination is instrumental in controlling the pandemic, but its success is challenged by vaccine hesitancy. Vaccine hesitancy is defined as a “delay in acceptance or refusal of vaccines despite availability of vaccination services” (8) and was emphasized among the 10 leading threats to global health in 2019 (9). Public acceptability of COVID-19 vaccination depends on the attitude of HCWs towards the vaccines (10). However, > 25% of Arab HCWs have been recently found to be vaccine-hesitant (11). Vaccine uptake by HCWs is key to vaccination success in the general population. Therefore, this study assessed COVID-19 vaccine acceptability and hesitancy among HCWs in Sana’a City, Yemen.
Methods
Study design and ethical considerations
We conducted a multicentre cross-sectional study from January to March 2022 among HCWs of both genders and any profession or qualification level from public and private health facilities in Sana’a. HCWs were included if they had not been vaccinated against COVID-19, provided written informed consent to participate, and satisfied the WHO guidelines for classifying and aggregating health professions (12).
The Ethics Committee of the Faculty of Medicine and Health Sciences, University of Science and Technology, Sana’a approved the study protocol (MECA No.: EAC/UST206). Additionally, this study complied with the WHO Research Ethics Review Committee checklist. Permission was also sought from health facility administrations. Written informed consent was obtained from HCWs who voluntarily agreed to participate after explaining to them the study purpose and ensuring data confidentiality.
Sample size and sampling method
Based on an assumed vaccine acceptability of 50% among HCWs, a confidence level of 95%, and precision of 5%, a sample of at least 383 HCWs was calculated using OpenEpi, version 3.01 (www.openepi.com). However, 391 HCWs were recruited using 2-stage cluster sampling. Four of 10 districts in Sana’a were randomly selected as the study clusters; namely, Ma’ain (west), Al-Wahdah (southwest), Shu’aub (northeast) and Assafi’yah (southeast). HCWs were conveniently sampled until we attained the required sample size from all hospitals and health centres whose administrations agreed on questionnaire distribution.
Data collection
Data about demographics, health profession, qualification level, years of experience, COVID-19 vaccine acceptability, and vaccine hesitancy and the reasons for it were collected using a self-administered structured questionnaire. The questionnaire was judged for content and face validity by 2 experts in community medicine and pilot-tested for clarity and length by 20 HCWs not included in the data analysis; after which, minor amendments were made to the content and format of the questionnaire.
Data analysis
Data were analysed using IBM SPSS Statistics version 21.0 (IBM Corp., Armonk, NY, USA). The proportion of vaccine-accepting HCWs was calculated with its 95% confidence interval (CI), and the reasons for vaccine hesitancy were calculated as proportions of the total number of vaccine-hesitant HCWs. Univariate binary logistic regression was used to test the association of independent variables with COVID-19 vaccine hesitancy, along with the corresponding odds ratios (ORs) and 95% CIs. Multivariable logistic regression was then performed to identify independent predictors of vaccine hesitancy, along with adjusted ORs (AORs) and 95% CIs. Statistical significance was set at P < 0.05.
Results
Characteristics of HCWs
The majority of HCWs were female (58.6%) and aged ≥30 years (62.4%), with a median age (interquartile range) of 33 (9) years (Table 1). More than half of HCWs were affiliated with the private sector, and most of them were working in hospitals (86.4%). Nursing professionals represented 28.6% of respondents, followed by laboratory professionals (25.6%) and clinicians (23.0%). More than half of HCWs held a bachelor’s degree and had ≤ 8 years of experience.
COVID-19 vaccine acceptability
Among the HCWs, 49.6% (95% CI: 44.6–54.7%) stated that they intended to accept COVID-19 vaccines when they became available. Specifically, 25.6% stated that they would be likely and 24.0% very likely to accept the vaccine, whereas 23.5% stated that they would be unlikely and 26.9% very unlikely to accept the vaccine.
Reasons for COVID-19 vaccine hesitancy
The most frequent reasons for vaccine hesitancy among HCWs were fear of adverse effects (77.7%), followed by concerns about unknown future effects (73.1%) and safety of novel vaccines (69.5%) (Figure 1). Just over 60% of vaccine-hesitant HCWs attributed their hesitancy to the perceived lack of vaccine necessity, doubt about vaccine efficacy, and the emergence of new virus variants. More than half of HCWs attributed their vaccine hesitancy to the perceived lack of disease risk, concerns about vaccine additives, lack of confidence in rapid vaccine development, and belief in the adequacy of other preventive measures. More or less than one third of HCWs ascribed their vaccine hesitancy to their belief in the adequacy of herd immunity (36.0%) and anti-vaccination media reports (28.4%). Not having direct contact with patients (15.2%) and having chronic diseases (9.1%) were the least frequently reported reasons for vaccine hesitancy.
Predictors of HCWs’ vaccine hesitancy
Vaccine hesitancy was significantly associated with being female (OR = 2.2, 95% CI: 1.5–3.4; P < 0.001), working in the public sector (OR = 2.3, 95% CI: 1.5–3.5; P < 0.001), and having ≥ 8 years’ experience (OR = 1.6, 95% CI: 1.1–2.5; P = 0.018) (Table 2). However, female gender (AOR = 2.5, 95% CI: 1.5–4.0; P < 0.001) and working in the public sector (AOR = 1.8, 95% CI: 1.2–2.9; P = 0.010) were independent predictors of vaccine hesitancy among HCWs.
Discussion
The effectiveness of vaccines to prevent and control COVID-19 is determined by their acceptability among the general population, which is influenced by HCWs’ vaccine acceptability. Nevertheless, there is disparity in vaccine acceptability by HCWs and the general population across regions and countries (13). Recently, vaccine acceptability was reported by 69% of HCWs in 12 countries across 4 continents, with high heterogeneity according to country income levels (14). In another study, the average vaccine hesitancy among HCWs was 22.5% (4.3–72%) (15).
Therefore, the present study assessed COVID-19 vaccine acceptability and the reasons for and predictors of vaccine hesitancy among HCWs in 1 of the most populous cities in a conflict-stricken country. The intention of around half of the HCWs to be vaccinated against COVID-19 is concordant with a nationwide survey in Yemen that found that 50% of the general population were willing to be vaccinated (16). In comparison, 61% of adults surveyed online from 4 major cities in Yemen were willing to be vaccinated within the first 2 weeks of the country’s COVID-19 outbreak (17). However, unlike facility-based studies, online COVID-19 surveys have shortcomings such as unreliable generalizability, survey fraud, and answering some or all questions without attempting to read or understand them because of disinterest or survey fatigue (17). Vaccine acceptability rates of 50.5–70% have been reported among HCWs in Saudi Arabia (18–21), compared with lower rates among HCWs in Egypt (21–45.9%) (22, 23) and Palestine (37.8%) (24). Although not inclusive, the above rates highlight disparities in vaccine acceptability across countries in the region. Over time, changes may occur following educational campaigns and other enabling factors.
The major reasons for vaccine hesitancy among HCWs in our study were related to safety concerns. Insufficient data on the safety of novel vaccines and concerns about their adverse effects were also the most frequent reasons for vaccine hesitancy among HCWs in Saudi Arabia and Egypt (18, 19, 21, 22). Second to safety, a major proportion of HCWs attributed their hesitancy to lack of vaccine necessity and doubts about efficacy. Consistently, distrust in vaccine efficacy was the most frequent reason for vaccine rejection by HCWs in Turkey (25). In contrast, < 20% of Egyptian and Saudi HCWs had doubts about vaccine effectiveness as a reason for hesitancy (21, 23). Several reasons may account for the perceived lack of vaccine necessity, including low perceived risk of infection, trust in one’s own health and immunity, and confidence in other preventive measures. Concerns about vaccine additives and expedited vaccine development accounted for vaccine hesitancy among more than half the HCWs in our study. Similarly, distrust of vaccine ingredients was among the most common reasons for vaccine rejection by Turkish HCWs (25), and lack of adequate clinical trials was the most common reason among Egyptian HCWs (22). Fear of unknown future adverse effects of rapidly developed vaccines may discourage people from vaccine uptake. Negative attitudes towards the vaccine should therefore be addressed through evidence-based communication to eliminate ambiguity about vaccine components and regulatory approval, and to foster vaccine acceptability by HCWs.
Emerging virus variants represent a major obstacle to vaccine acceptability, and this accounted for ~60% of vaccine hesitancy among HCWs in our study. Although emerging variants may evade vaccine-induced immunity and adversely affect vaccine confidence, hesitancy and low uptake and coverage can increase the risk of emergence of variants (26). The perceived lack of COVID-19 risk by more than half of vaccine-hesitant HCWs in this study could be explained by the downward trend in cases and absence of systematic monitoring of the impact of COVID-19 on the healthcare workforce. The disproportionate toll of COVID-19 on HCWs in Yemen has been highlighted, with 97 deaths as of 22 July 2020 (27). Anxiety about the risk and severity of COVID-19 have been reported to predict an intention for uptake of COVID-19 vaccination at the national level (16). In Saudi Arabia, 20% of HCWs had doubt about the risk of COVID-19 (21), compared with 56.9% in our study (21). The low perceived risk can be attributed to the large amount of misinformation and disinformation. For instance, ~20% of Yemeni adults believe that viruses are produced as biological weapons (17). In this study, half of vaccine-hesitant HCWs considered using nonvaccine preventive measures as an adequate alternative. While using such measures helps reduce exposure, adherence may not prevent COVID-19. According to WHO guidance (28), even vaccinated people in healthcare facilities should adhere to social and public health measures to prevent or limit transmission. Therefore, augmenting COVID-19 preventive measures with vaccination is critical.
The upsurge in anti-vaccination media reports and their rapid propagation through many channels, especially social media, has had a negative impact on pro-vaccination attitudes of HCWs. This impact was manifest in our study, where approximately one third of HCWs attributed their hesitancy to media reports opposing COVID-19 vaccination. The likelihood of vaccine hesitancy increased among Yemeni adults who thought that the virus was human-made for the financial gain of pharmaceutical companies (17). Gaps in evidence-based sources of COVID-19 vaccine information play a role in the spread of fake news on different media outlets and platforms. Therefore, misinformation, rumours, and conspiracy theories through traditional and social media must be debunked with evidence-based strategies. It is noteworthy that only a quarter of HCWs in Sana’a reported peer-reviewed journal articles as their major source of COVID-19 information, compared with > 60% for television/radio and social media (29). Also, 57% of Yemeni HCWs reported social networks and news media as their major COVID-19 information sources (30). Therefore, HCWs should be advised to obtain verified information from trustworthy and credible sources, such as WHO platforms, peer-reviewed journals, and mainstream media.
Approximately one third of HCWs in our study were vaccine hesitant because of beliefs about adequate protection through herd immunity. Herd immunity is difficult to assess in Yemen because of the weak COVID-19 surveillance system and paucity of community-based seroprevalence studies. A recent study claimed that Yemen is probably moving towards herd immunity, as demonstrated by the small number of cases and deaths despite the limited restrictions, and freedom of movement and gathering (31). Given that vaccination coverage is expected to be difficult, herd immunity has been postulated as the only option against COVID-19 in Yemen (31). However, achieving herd immunity against COVID-19 has been more complicated than expected (32). For instance, allowing community transmission without mandatory protective measures led to a 10-fold increase in mortality in Sweden compared to neighbouring countries (33).
The least frequent reasons for vaccine hesitancy among HCWs in our study were lack of direct patient contact and having chronic diseases. In contrast, there was a significant association between contact with COVID-19 patients and vaccine acceptability among Egyptian HCWs (22). The hesitancy of ~10% of vaccine-hesitant HCWs due to chronic diseases raises concerns because patients with chronic conditions are more vulnerable to greater disease severity and mortality, and more likely to be receptive to vaccination (15, 34). While WHO has prioritized vaccination of people with underlying conditions (28), safety concerns and potential adverse effects are major reasons for vaccine hesitancy in chronically ill patients (34).
The finding that female gender was an independent predictor of vaccine hesitancy in our study is consistent with that reported for the general Yemeni population (16, 17) and HCWs elsewhere (15, 19, 21, 22, 24). Pregnancy and trying to conceive can be major reasons for vaccine hesitancy. In the United States of America, pregnant HCWs and those who were trying to conceive were 2- and 3-fold more likely to reject COVID-19 vaccination, respectively (35). Apart from concerns about the potential adverse reproductive effects of novel vaccines, there is a need for further studies to explore the reasons for vaccine hesitancy among female HCWs. The lack of association between HCWs’ age and vaccine hesitancy in our study is consistent with that reported for Egyptian HCWs (22) but not for the general Yemeni population (17) and HCWs in Saudi Arabia (20).
In Sana’a City, a significantly higher level of knowledge about COVID-19 has been reported among physicians than nurses (30). However, profession was not significantly associated with vaccine hesitancy in the present study, which agrees with a study in Egyptian HCWs (22). In Palestine, physicians were significantly associated with intention to be vaccinated (24). The lack of association between HCWs’ qualification level and vaccine hesitancy in our study is consistent with that reported for HCWs in Asia–Pacific countries (36). We found no association between the length of work experience and vaccine hesitancy among HCWs. However, vaccine hesitancy was independently predicted by health sector type, with COVID-19 vaccines being 2-fold more likely to be rejected by public sector HCWs. This could be partly explained by different health administrations’ attitudes towards COVID-19 vaccination in both sector types. Exploring the difference in vaccine hesitancy between HCWs in public and private health sectors should be assessed using comparative studies.
Our study was limited by being facility-based, which means that it may not be possible to generalize the findings to HCWs throughout the country. However, as a multicentre study, the results provide preliminary insights into vaccine acceptability as well as the reasons for and predictors of vaccine hesitancy among HCWs using self-administered questionnaires rather than online surveys through social networks. Although HCWs’ attitudes towards COVID-19 vaccination may change over time for several reasons, such as awareness-raising campaigns and future availability of evidence, our results provide baseline information to help monitor the change in vaccination intention and reasons for hesitancy. Another limitation might be selection bias as a result of convenience sampling. However, administrative and logistic constraints made it difficult to have the entire HCWs’ sampling frame. This included not having a database of all HCWs in the city, and refusal of some administrations of health facilities to take part in the study. It is noteworthy that convenience sampling in this survey generated a hypothesis of comparable proportions of vaccine-accepting and -hesitant HCWs for future surveys. The random selection of study clusters (districts) prior to convenience sampling could help reduce the selection bias.
Conclusion
When COVID-19 vaccines became available, around 50% of HCWs in Sana’a City intended to accept vaccination. Concerns about the safety of novel vaccines, and fear of adverse and unknown future effects are the major reasons for vaccine hesitancy, followed by the perceived lack of vaccination necessity, doubts about vaccine efficacy, and emerging virus variants. More than half of vaccine-hesitant HCWs perceive that COVID-19 is not risky, are concerned about vaccine additives and rapid development in an emergency, and consider other preventive measures adequate. Misplaced belief in the adequacy of herd immunity and misinformation through anti-vaccination media reports also contribute to vaccine hesitancy among HCWs. Female gender and working in the public health sector, but not age, profession, qualification level, length of experience, or type of health facility, are independent predictors of vaccine hesitancy.
Acknowledgements
We thank the hospital administrations for permission to conduct the survey and the HCWs who participated in this study.
Conflict of interest: The authors declare no conflict of interest.
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