JFOA Journal

Introduction

Influenza is a common respiratory illness caused by influenza virus types A, B or C [1]. Influenza type A is considered the most severe type of influenza and the subtype H1N1 virus was responsible for the recent influenza pandemic [2]. Type B causes a less severe illness and is more frequent in children and Type C causes a flu-like disease and usually has an uncomplicated course [2]. It is estimated that about 9% of the world’s population is affected by influenza annually accounting to nearly one billion infections and three to five million severe cases, and deaths annually [3]. In United States (US), nearly 20% of the population is affected annually with around 225,000 hospitalizations every year [4].

Saudi Arabia deserves greater attention as it serves as an abode for major pilgrimage center with an annual turnover of millions of pilgrims from around the globe. There is a high risk for transmission of infection posing major threat to the health of airport personnel, healthcare staff, security personnel and civilians. Moreover, the most effective way to prevent infection with the influenza virus and its potentially severe complications is immunization. Hence, Saudi Thoracic Society recommends adoption of strict vaccination strategies [5].

Healthcare Workers (HCWs) are often in contact with patients, so they are considered a potential source of transmission [6]. Hence, the World Health Organization (WHO) recommends influenza vaccination for HCWs [7]. The influenza vaccine is safe and well tolerated and can prevent up to 70%-90% of influenza cases in healthy adults [8,9]. Immunization of HCWs has been associated with improvements in patient safety and decreased morbidity and severe mortality in hospitals and other healthcare facilities [10-16]. Moreover, vaccination of HCWs reduces workplace absences, delivers economic benefits for healthcare systems, and provides cost savings for healthcare organizations [10,17,18]. Despite studies showing that vaccination is effective among medical personnel and reduces influenza transmission and mortality among hospitalized patients, the uptake is still suboptimal [19]. The WHO and the Center of Diseases Control and prevention-US (CDC) have endorsed the promotion of the flu vaccine [10,20]. The WHO has aggressively campaigned for the importance of the flu vaccine program both nationally and internationally. The WHO and the CDC declared that the seasonal flu vaccine is safe, and the most effective in the protection against the flu and avoidance of severe complications and hospitalization [21,22].

In a study conducted in US, 2005-06, 59% of the registered nurses found have received the influenza vaccine [23]. The most common reason for being vaccinated was protecting oneself from illness (95%), whereas the most common reason for not being vaccinated was concern about adverse reactions (39%) [23]. However, another study carried out also in US in the same year estimated the influenza vaccine uptake as 38% among HCWs [24]. In Singapore in season 2004-05 influenza vaccination rates among HCWs were found to be more than 50%, 65% and 70% among doctors, nurses and, ancillary staff respectively [25]. In a study conducted in US, 2010, 75.2% of the respondents reported agreeing with the new mandatory policy. Most respondents (72%) believed that the policy is coercive, but more than 90% agreed that the policy is important for protecting patients and staff and considered it as part of professional ethical responsibility [26].

During 2007-08, the Emergency Service (EMS) staff in North Carolina believed that influenza vaccine is ineffective [27]. Similarly, in 2008, in Greece, nurses who hesitated influenza vaccination found to hold low perceived susceptibility and vaccine effectiveness [28]. Such HCWs thought that, not making it mandatory support their perception [27,28]. Furthermore, in 2009, HCWs from a teaching hospital in France hesitated vaccination doubted increased susceptibility and vaccine safety [29]. Hence, only 22% of sampled HCWs from that Hospital received the seasonal influenza vaccine. However, the rate was significantly higher among physicians, as 45% of them have received the vaccine. The main reasons given for accepting of the seasonal were “protection of the patient” and “self-protection” [29]. In his study in 2009, in Hong Kong public hospitals, Chor et al. assessed the willingness of HCWs to receive the influenza vaccine [30]. Positive factors associated with HCWs’ willingness to vaccinate included prior vaccination and their perceived risk for acquiring influenza. Barriers to willingness to vaccinate included fear of the vaccine’s adverse effects and uncertainties about efficacy [30].

Regionally, in 2010, the influenza vaccination rates among HCWs in United Arab Emirates, Kuwait and Oman were 24.7%, 67.2%, and 46.4% respectively [31]. About 59% of the vaccinated HCWs were

motivated by self-protection [31]. On the other hand, 31.8%, 29.4%, 17.3%, 24.9%, 20.1% of unvaccinated HCWs claimed lack of time, unawareness of vaccine availability, unawareness of vaccine importance, and doubted vaccine effectiveness and safety [31]. Furthermore, 25.4% claimed missing vaccination due to actual unavailability of the vaccine [31]. In Saudi Arabia, the influenza vaccination rate among HCWs in season 2008-09 was 41% [32]. The total coverage rate for the period between 2003 and 2008 was 69%. Half of the vaccinated HCWs received one to three out of the five shots [32]. While 63.9% thought that the influenza vaccine is important, 35% believed that they are not at risk of influenza [32]. Moreover, 66.8% perceived influenza vaccine as unsafe and 62.3% perceived influenza as non-serious disease [32]. In contrast to those high rates, only 5.9% of HCWs who covered medical works during 2007 Hajj season had received the influenza vaccine [33].

Methods

This cross-sectional study was conducted in Riyadh, Saudi Arabia between 27 May and 15 June 2017. The study targeted HCWs in WHC-PSMMC however; HCWs ineligible for treatment in PSMMC and those covering peripheral clinics or on leave during data collection have been excluded. The study aimed to estimate the influenza vaccination uptake among HCWs and its relationships with socio-demographic factors, work and health-status related factors, and beliefs towards influenza infection and vaccine. A random sample of 240 HCWs stratified by their occupation to physicians, nurses, and others (pharmacists, admins, translators, X-ray technicians, health educators, social workers, and dietitians) were recruited. Data were collected using a self-administrated well-structured validated questionnaire to get the relevant data needed for the study. The questionnaire was initially prepared in English language and then translated into Arabic language and back into English following the cross cultural translation guidelines. After signing an informed consent form, each participant completed the validated questionnaire. The independent variables included socio-demographic characteristics such as age, gender, marital status, and nationality, level of education, occupation, work experience, and income. They also included work and health status related data and beliefs towards influenza vaccine and disease. The dependent variable was level of influenza vaccine acceptance.

Statistical analysis was done using SPSS 16. Results were presented as means and standard deviation, medians, and interquartile range for quantitative data, frequencies and percent for qualitative data. Independent t-test was used to compare quantitative variables between the two vaccinated and unvaccinated HCWs. Chi-square and Fisher exact tests were used for comparing qualitative variables between the two groups. Multivariate logistic regression analysis was carried out to ascertain the association of vaccination uptake among HCWs with the proposed influencers. Scoring system was developed for transformed categorical variables like beliefs about influenza disease and vaccine and it was as follow; 1 for strongly disagree, 2 for disagree, 3 for neutral, 4 for agree and 5 for strongly agree. The maximum score was 20 for beliefs towards the infection and 30 for beliefs towards the vaccine. An ethical approval for this study was obtained from ethics review committee in PSMMC.

Results

Out of the 240 randomly selected HCWs, 200 have completed and returned the questionnaires. Almost 58% of the respondents were males. The age of most of the respondents (85%) was below 41 years. In consistent with their age range, most of the respondents (68%) found have work experience of less than 10 years. Most of the respondents were Saudi (79%), and 67.5% of the participants were married. While 84.5% of them were degree holders, only 15.5% were non degree holders. About 23% of the participants were physicians, 25% were nurses, and the remaining 52% were classified as others. Majority of participants (67.0%) were doing clinical work. The income of 53% of the participants exceeded 10,000 Saudi Riyal (SAR) (Table 1). About 40% of the respondents reported history of influenza infection. On the other hand, while 28% reported that they have never vaccinated against influenza before, 50% claimed that they have received it twice or more. Health wise, 13% of the respondents gave a history of chronic diseases. Only 41% found have received the influenza vaccine of the year 2016.

On univariate analysis gender, nationality, occupation, level of education, work nature, work experience, history of influenza infection, and previous influenza vaccination were associated with the recent vaccination. Females were 2.5 times more likely to vaccinate with the flu vaccine than male. The non-Saudi HCWs were 6.9 times keener to vaccinate compared to the Saudi ones. Physicians and nurses were 5.9 and 2.6 times more likely to receive the influenza vaccine than other HCWs, respectively. The higher was the level of education, the more was the odd of vaccinating against influenza. Unexpectedly, no association existed between having a chronic diseases and flu vaccination uptake. Unfortunately, about 50% of respondents with chronic diseases have not received the influenza vaccine. Moreover, only 54% of those have bronchial asthma and 50% of the diabetics have vaccinated. The more experienced the staff, the higher was the odd to vaccinate compared to less-experienced. HCWs who reported past influenza infection and those who received the flu vaccine more than once in their lifetime tended to accept the vaccine more with an (Odd Ratios) ORs of 2.1 and 9.5 respectively. Moreover, HCWs who were doing clinical works were more wildlings to receive the vaccine (Table 2).

Although 69.5% of the respondents believed that influenza can lead to complications and 80% thought that HCWs are at greater risk, only 50% thought of it as a serious disease and 87.5% considered it as an easily treatable disease. Furthermore, on univariate analysis vaccinated HCWs were more likely to perceive the influenza to have serious complications, the mean, median, and interquartile range of the score of perceiving the influenza as a serious infection did not differ between vaccinated and unvaccinated HCWs. Moreover, despite higher mean, median, and interquartile range of the score of perceived susceptibility to influenza among vaccinated HCWs compared to unvaccinated HCWs, the difference in the means were statistically insignificant. The influenza was perceived as more difficult to treat among the vaccinated HCWs than the unvaccinated HCWs. These findings were reflected in higher total score of negative beliefs toward influenza among vaccinated than unvaccinated, however insignificant difference.

On the other hand, as 49% of the HCWs agreed that flu vaccine has severe side effects or adverse reaction, 52% thought that vaccine costs outweigh its benefits. Moreover, as 62.5% and 63.5% of the respondents believed that it is safe and effective respectively, 66.6% agreed that it prevents the spread of infection to patients. Furthermore, on univariate analysis vaccinated HCWs were significantly more likely to perceive the influenza vaccine as safe, effective, and to reduce susceptibly and communicability. The means, medians, and interquartile ranges of the scores of these perceptions towards the influenza vaccine differed significantly between vaccinated and unvaccinated HCWs. Moreover, despite higher mean, median and interquartile range of the score of perceived side effects and that they outweigh the benefits of influenza among vaccinated HCWs compared to unvaccinated HCWs, the difference in the mean were statistically insignificant. These findings were reflected in significant higher total score of positive beliefs score toward influenza vaccine among vaccinated than unvaccinated (Table 3).

Binary logistic regression analysis was done to ascertain about the associations of the studied characteristics and attitudes of HCWs with the vaccination uptake among HCWs. The adopted model adjusted for the potential co-variables including the socio-demographic, work- and health- related factors. Nationality, beliefs towards vaccines, and nature of work were associated with vaccination against influenza. HCWs perceived influenza vaccine as beneficial, non-Saudi and those doing clinical work were more likely to vaccinate against influenza (Table 4).

Discussion

It is well established fact that influenza vaccination of medical students and other healthcare staff reduces the transmission of infection [34]. Influenza is given high priority in Saudi Arabia where numerous reports of different types of influenza outbreaks have occurred in recent years [35]. A great number of the participants (59%) had not received the influenza vaccine. The study may have overestimated the vaccination uptake as participants’ vaccination status was self-reported. Despite being more or less consistent with the global and regional suboptimal HCP vaccination uptake, rates seemed to be higher than previous local estimates. There were many similar studies performed, for instance, Al-Shammari reported vaccination rates as low as 38% among HCWs [36]. Furthermore, a study targeted Middle Eastern region, reported vaccination rates of 24.7%, 67.2% and 46.4% in UAE, Kuwait and Oman, respectively and concluded that the vaccination rates among the HCWs were suboptimal [31].

Females usually tend to adopt healthy lifestyles compared to male. In addition, physicians, nurses, and postgraduates are expected to be more knowledgeable. Staff other than physicians and staff with low education level usually have low income. They are less aware of the threat of influenza and the importance of its vaccine. The education and work backgrounds can explain this association. Older staff, HCP performing clinical works, HCP with a history of influenza, and those who vaccinate many times may have been exposed to more events related to influenza, and its vaccine. Males, and young usually tend not to adopt healthy behaviours and are more likely to hesitate vaccination. Non-clinical staff may have low education level and then less knowledgeable about influenza and its vaccines, so more likely to hesitate vaccination. Therefore, staff doing non-clinical works are expected not to perceive the importance of vaccination as clinical staff. Furthermore, non-Saudi staff is expected to show more commitment towards the recommendations adopted by their employee, as they are expected to meet their job requirements. Consistent with these findings European study highlighted the role of low knowledge among its medical students and concluded that lower

knowledge levels along with decreased risk perception during early years of medical graduation studies are key determinants of lower vaccination rate [37].

In this study, vaccinated and unvaccinated HCWs perceived the threat of influenza almost similarly. Inconsistent with these findings, many studies revealed and association between perceived susceptibility and seriousness with vaccination uptake behaviour. A meta-analysis of 34 studies with a total population of 15,988 showed a strong relationship between the different perceived threat and vaccination uptake [38]. On the other hand, most of the vaccinated HCWs in the current study believed that vaccine controls and prevents the spread of influenza and that it is safe and effective. A positive association existed between holding positive beliefs towards the influenza vaccine and the vaccination. Furthermore, perceiving a mean as safe and effective to avert the risk of health threats lead to accepting that mean. However, perceiving an issue as a threat and a mean as effective is not isolated from factors like sociodemographic factors.

In Italy, studies have been conducted to investigate the attitudes and knowledge of HCWs and medical students regarding seasonal or pandemic influenza, or both types of influenza vaccines [39-41]. Perceiving influenza as a serious illness with availability of an effective vaccine and understanding that one may transmit influenza were all lower in the “never vaccinated” group than in the “always vaccinated” and “sometimes vaccinated” groups. HCWs with weak knowledge about influenza may not believe they are at greater risk. Similarly, HCWs who get information about influenza vaccine from the media may not believe in vaccines’ effectiveness and safety. For that reason, it is important to increase the level of knowledge regarding the risk of acquiring and transmitting influenza in the workplace and to encourage adoption of preventive measures. For the “always vaccinated” and “sometimes vaccinated” groups, the purpose of public health interventions could be to maintain and support their level of influenza awareness and knowledge through informational campaigns in workplaces [42].

In Italy, while the perceived effectiveness of the influenza vaccine was higher among vaccinated HCWs, perceived costs of the vaccine were higher among unvaccinated [43]. HCWs from four European countries hesitated vaccination were worried about the side effects of the vaccines; however, concerns about vaccines were not limited to effectiveness and safety [44]. Concerns about vaccines varied by regions and contexts, which entail consideration of social, economic, and cultural aspects [44]. In a systematic review of 37 studies about H1N1 vaccine uptake in 2009, both perceived threat and benefits were good predictors of both intention and actual uptake [45]. Similarly, older people, males, ethnic minorities, and physicians were good predictors of both intentions to vaccinate and actual uptake. People who vaccinated previously and those who received cues from their society or trusted sources were more likely to vaccinate [45]. The independent predictors of influenza vaccine uptake in Turkey included the place of work, exposure to cues, having a chronic condition, and perceived vaccine effectiveness [46]. Another study in Turkey showed that a physician, uptake of the last flu vaccine, perceived safety of the H1N1 vaccine, and agreeing to ethical responsibility were independently associated with vaccine uptake [47]. On the other hand, not trusting the effectiveness of the

H1N1 vaccine and scaring its adverse reactions were independently associated with hesitating vaccination [47]. The influenza vaccine uptake among ever-vaccinated nurses in Hong Kong was independently associated with the perceived usefulness and cues to vaccinate [48]. Perceived risk of influenza and perceived usefulness of the vaccine were independently associated with intention to vaccinate, as shown in a study done in Italy [48].

Conclusion

Despite restrict recommendations, rate of flu vaccine uptake was still suboptimal. While both vaccinated and unvaccinated HCWs held negative beliefs about the influenza disease similarly, a positive association existed between beliefs in influenza vaccine as beneficial, safe and effective mean to control and prevent influenza, and vaccination among vaccinated HCWs. Moreover, non-Saudi and staff doing clinical work were also independently keener to vaccinate against the influenza. The suboptimal vaccination uptake may reflect the attitude of unvaccinated HCWs towards their patients as they may not be keen to recommend vaccination to them. The study was limited by self-reporting of vaccination status. Furthermore, the study have not considered for other influencers like cues to vaccinate and self-efficacy. More studies on different societies and larger sample size are needed to confirm the findings of this study. More elaborated studies are needed to find about knowledge, psychological, and health related perspectives of influenza immunization. As this study is limited to a single source of sample population, generalizability is restricted.

Tables

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