Bonet‑Esteve et al. BMC Fam Pract (2021) 22:84 https://doi.org/10.1186/s12875-021-01434-8 RESEARCH Open Access Influenza vaccination during the coronavirus pandemic: intention to vaccinate among the at‑risk population in the Central Catalonia Health Region (VAGCOVID) Anna Bonet‑Esteve1,2, Raquel Muñoz‑Miralles3*, Carla Gonzalez‑Claramunt4, Ana M Rufas5, Xavier Pelegrin Cruz6 and Josep Vidal‑Alaball2,7,8 Abstract Background: Influenza is a major public health issue, with the primary preventive measure being an annual influ‑ enza vaccination. Nevertheless, vaccination coverage among the at-risk population is low. Our understanding of the behaviour of the influenza virus during the SARS-CoV-2 coronavirus pandemic is limited, meaning influenza vaccina‑ tion is still recommended for individuals at risk for severe complications due to influenza infection. The aim of the study is to determine the intention to vaccinate against seasonal influenza among the at-risk population in the 2020- 21 campaign during the SARS-CoV-2 pandemic and to analyse the factors which influence such intention. Methods: Cross-sectional telephone survey of adults (aged over 18) with risk factors in central Catalonia where the need for the Seasonal Influenza Vaccine (SIV) was recommended. Results: A total of 434 participants responded to the survey, 43.3% of whom intended to be vaccinated against influenza for the 2020-2021 influenza season, 40.8% had no intention to be vaccinated and 15.9% were uncertain or did not express their opinion. The intention to get vaccinated against influenza is associated with having depend‑ ents, the individual’s perception of the risk of being infected with influenza and the perceived risk of transmission to dependents. It is also associated with age, whether the individual had received influenza vaccine the previous season or any other season before. The best predictors of the intention to vaccinate are the individual’s perception of the risk of catching influenza and whether the individual had been vaccinated in the previous season. Conclusions: Intention to vaccinate can be a good predictor of individual behaviour in relation to vaccination. During the current SARS-CoV-2 pandemic many individuals are hesitant to influenza vaccination. In order to improve influenza vaccination coverage in people included in risk groups, it is necessary to promote educational actions, espe‑ cially among those who express doubts. Keywords: Human influenza, Influenza vaccines, Intention, COVID-19, Health Knowledge, Attitudes, Practice, Vaccination refusal, Vaccination coverage *Correspondence: rmunozm.cc.ics@gencat.cat 3 Centre d’Atenció Primària Plaça Catalunya, SAP Bages-Berguedà- Solsonès, Gerència Territorial Catalunya Central Institut Català de la Salut, CAP Plaça Catalunya. C/ Soler i March 6, 08242 Manresa, Spain Full list of author information is available at the end of the article © The Author(s) 2021. Open Access This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons licence, and indicate if changes were made. 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BMC Fam Pract (2021) 22:84 Page 2 of 9 Background SIV coverage in Catalonia during the 2018-19 influenza Influenza becomes a major public health problem every vaccination campaign for people aged 65 years and older year as a result of the high rates of morbidity which occur was 51%, similar to that of Spain (54.3%), yet in those during the successive waves of the epidemic and the pres- under 60 years it was only 15.86% [1]. In people aged 60 ence of complications and excess mortality in specific to 64 and pregnant women the coverage was 20% and population groups [1, 2]. 29.2% respectively. In Spain, on the other hand, coverage It is estimated that influenza can affect between 5% and was 22.3% in the 60-64 age group and 40.6% in pregnant 20% of the general population and 50% of institutional- women [8]. ized populations. In previous years, it is estimated that Influenza vaccination coverage rates fall a long way up to 25% of acute febrile respiratory conditions could short from the 75% target proposed by the World Health be caused by the influenza virus in Catalonia. This symp- Organization (WHO) and the European Centre for Dis- tomatology generates a significant number of medical ease Prevention and Control (ECDC). For the 2020-21 consultations and workday loss as a result of the disease influenza vaccination campaign in Catalonia and Spain, and its convalescence, which can last from a few days to a the goal has been set to achieve or exceed 75% of vacci- few weeks [1]. nations in people aged over 65 and in healthcare profes- In some cases, the disease can become more severe sionals, and 60% in pregnant women and people with a due to the influenza virus or a secondary, usually high risk for complications [6, 9]. bacterial, infection which most commonly mani- According to a review of 48 articles on SIV [10], the fests itself as pneumonia, and may even prove fatal. main barriers to vaccination among the general popu- At other times it can present in the form of cardio- lation and even among health professionals are lack vascular disease, myocarditis or encephalitis, which of awareness and knowledge of influenza and miscon- can also be fatal. Nevertheless, frequently the initial ceptions about the disease and the vaccine used in its influenza infection goes undiagnosed and is not usu- prevention. ally recorded as the cause of death in death certifi- With respect to the current SARS-CoV-2 pandemic, cates. Overall influenza-associated mortality has been the 2020-21 SIV campaign is expected to be influ- estimated to 13.8 per 100,000 person-years in Europe. enced by a lack of knowledge as to the behaviour of Complications can occur in anyone, although hospital- the influenza virus and the risk of coinfection by both izations are more common in the elderly (≥ 65 years, viruses. For this reason, health authorities support an 309/100,000 person-years) and in young children (<1 increase in SIV coverage among at-risk groups in order year, 151/100,000 person-years) [3]. to reduce the number of cases which occur during the Influenza virus is transmissible from one day before the peak of the influenza season and their impact on the onset of symptoms to 4 days after. Although young chil- healthcare system [6, 9]. dren and people with weakened immune systems, might Behaviour, seen as a set of individual or collec- be able to infect others for a longer time. Between 30% tive actions, is a fundamental factor which influences and 50% of individuals infected with the influenza virus human health. Certain behaviours related to health or may be asymptomatic, though they may pass it on to oth- illness are difficult to modify since, although they may ers through respiratory droplets [4]. not be unhealthy, they are thoroughly entrenched in The Seasonal Influenza Vaccine (SIV) is the primary individuals or groups. According to Ecological Systems preventive measure to prevent influenza and its compli- Theory, changes in behaviour with respect to vaccina- cations [1, 5]. In Catalonia and most neighbouring coun- tion, depend on numerous factors which influence it: tries, it is generally recommended for at-risk populations, personal factors which make an individual accept or that is, people with underlying conditions or personal reject a vaccine, and also the sociocultural factors and circumstances that make them more susceptible to com- the broader geographical and temporal context in which plications or decompensation, leading hospital admis- they live [11]. sions and higher mortality rate [6]. According to Ajzen’s Theory of Planned Behaviour In the Northern Hemisphere, vaccines are adminis- [11, 12], intention is a key determinant of action. For tered in early autumn, before the winter season begins this reason, it is important to find out what the at-risk [7]. Since the level of vaccine coverage tends to be low population’s intentions are with respect to the SIV dur- among the general population, due to both the strategy ing the current SARS-CoV-2 pandemic [13]. Also, it is of specifically recommending vaccinations to the at-risk relevant to examine whether the protective measures population and the low coverage achieved in this group, put in place to mitigate COVID-19 transmission can it is difficult for the SIV to achieve a significant decrease influence individuals in their decision to get vaccinated in influenza incidence in the community. against influenza [14]. Bonet‑Esteve et al. BMC Fam Pract (2021) 22:84 Page 3 of 9 The aim of the study is to determine the at-risk popu- Table 1 Priority groups for influenza vaccination lation’s intention to vaccinate against seasonal influenza At-risk groups for influenza vaccination during the 2020-21 flu campaign in the Central Cata- lonia Health Region, in the midst of the SARS-CoV-2 People aged 60 or over pandemic. The specific objectives of the study are: 1) People under 60 years, at high risk of complications from influenza: • Adults with chronic cardiovascular (including hypertension), neuro‑ To assess the perception of the risk of catching seasonal logical, or respiratory disease (including asthma, bronchopulmonary influenza during the SARS-CoV-2 pandemic. 2) To deter- dysplasia, and cystic fibrosis). ○ Diabetes mine whether contextual factors related to the increased • Adults with: physical and hygiene protective measures put in place ○ Morbid obesity (body mass index ≥ 40 in adults) ○ Chronic kidney disease and nephrotic syndrome ○ Hemoglobinopathies and anaemia during the pandemic [14] influence the intention to be ○ Haemophilia, other coagulation disorders and chronic bleeding disor‑ vaccinated against influenza. ○ Asplenia or severe splenic dysfunction ders, as well as recipients of blood products and multiple transfusions ○ Chronic liver disease, including chronic alcoholism ○ Severe neuromuscular diseases Methods This is a cross-sectional study on the intention to receive ○ Immunosuppression ○ Cancer and malignant haematological diseases ○ Cochlear implant or waiting to receive one the influenza vaccine and risk perception of contracting ○ Cerebrospinal fluid fistula seasonal influenza during the SARS-CoV-2 pandemic in a sample of the at-risk population by means of a tel- ○ Celiac disease ○ Chronic inflammatory disease ○ Disorders and diseases that lead to cognitive dysfunction: Down ephone survey. The influence of the contextual factors related to increased hygiene/physical measures during syndrome, dementia and others the pandemic were also evaluated. The questionnaire used (Additional file 1) is based on an earlier survey con- ducted by Apiñaniz to study the acceptability of an influ- enza A (H1N1) vaccine [15]. The telephone survey of participants was conducted by The study was conducted in the Central Catalonia four interviewers who had previously attended a training Health Region, which includes the counties of Anoia, session for standardisation purposes and to avoid differ- Bages, Berguedà, Moianès and Osona. The duration of ences in the interpretation of the answers. A randomized the study was from October 1 to 15, 2020,15 days before list of individuals belonging to the study group was made the start of the influenza vaccination campaign .The study available and those who met the inclusion criteria were population is made up of those individuals registered at included, until the number of participants required for the Primary Care Teams (PCTof the Catalan Institute of the sample was obtained. Health of Central Catalonia, consisting of approximately A descriptive statistical analysis was performed on the 400,000 individuals. data resulting from the answers to the questionnaire. Cat- The inclusion criteria were: 1) Individuals aged over egorical variables were described using frequencies and 18 years. 2) Eligible for influenza vaccination because of percentages. Continuous variables were described with their at-risk group condition (people with underlying ill- mean and standard deviation. The proportions of cat- nesses which make them more susceptible to complica- egorical variables were compared using Fisher’s exact test tions or decompensations) (Table 1) [5]. 3) To have given or Pearson’s chi-square test and the t-test for continuous written authorization to be contacted by telephone to variables. The best fit model for logistic regression was receive health information. 4) To have given informed used to predict intention to vaccinate using the Bayesian consent to participate in the study on a voluntary basis. Information Criterion, only taking into account variables The exclusion criteria were: 1) A language barrier. 2) with significant association with intention to vaccinate Incorrect phone number or failure to answer a call after a For later validation of the model, the data were split into maximum of two attempts at different times. 3) Individu- the training set (80%) and the validation set (20%). als who were uncapable of understanding the nature of The R Project for Statistical Computing for Windows the study. 4) Individuals living in institutions. (version 3.6.3) was used for statistical analysis. In the The sample size was calculated using the GRANMO resulting data that were unrepresentative, levels were calculation programme [16]. It was calculated that a simulated or eliminated in order to obtain an approxi- random sample of 427 individuals was sufficient to esti- mate p-value. Results with a p-value higher than 0.05 mate, with a 95% confidence level and a margin of error (p<0.05) were considered statistically significant. of +/- 5%, a population percentage which is expected The study protocol was approved by the University to be around 51%. The replacement rate was estimated Institute for Primary Care Research (IDIAP) Jordi Gol to be 10%. Health Care Ethics Committee (Code 20/177-PCV). Bonet‑Esteve et al. BMC Fam Pract (2021) 22:84 Page 4 of 9 Results Fifty four (12.4%) participants had children at their A total of 434 individuals with risk factors were inter- care and 51 (11.8%) cared for a dependent person. Of viewed of whom 258 (59.4%) were women. The average these, 34 (32.4%) were of the opinion that this year age of the respondents was 60 years, with an age range the individuals at their care had a high risk of catch- between 20 and 100, and 152 (35%) were under 60 years ing influenza, while 49 (46.7%) participants believed old. Four hundred and five (93.3%) participants were of that they did not. One hundred and fifty-five (35.7%) Spanish origin and 206 (47.5%) were educated to primary respondents had been vaccinated against influenza level. Three hundred and seven participants (70.7%) lived the previous year and 216 (49.8%) had been vacci- with a partner and 217 (50.0%) were retired (Table 2). nated in another season (Table 3). Table 2 Participants’ influenza vaccination intention and sociodemographic characteristics VARIABLE Yes No DK/NO Total p Intention to have SIV 188 (43.3) 177 (40.8%) 69 (15.9%) 434 (100%) Gender 0.811 Male 79 (44.9%) 71 (40.3%) 26 (14.8%) 176 (40.6%) Female 109 (42.2%) 106 (41.1%) 43 (16.7%) 258 (59.4%) Other 0 (0%) 0 (0%) 0 (0%) 0 (0%) Age <0.001 Average 65 (12.8) 58 (12.2) 60 (13.7) Age by group <60 42 (27.6%) 82 (53.9%) 28 (18.4%) 152 (35.0%) 60-70 82 (45.1%) 73 (40.1%) 27 (14.8%) 100 (23.0%) >70 64 (64.0%) 22 (22.0%) 14 (14.0%) 182 (41.9%) Origin 0.245 Spanish national 171 (42.2%) 168 (41.5%) 66 (16.3%) 405 (93.3%) Foreigner 17 (58.6%) 9 (31.0%) 3 (10.3%) 29 (6.7%) Education level 0.016* No studies 12 (63.2%) 3 (15.8%) 4 (21.1%) 19 (4.4%) Primary level 98 (47.6%) 72 (35.0%) 36 (17.5%) 206 (47.5%) Secondary level 42 (33.6%) 63 (50.4%) 20 (16.0%) 125 (28.8%) Higher education 35 (42.2%) 39 (47.0%) 9 (10.8%) 83 (19.1%) DK/NO 1 (100%) 0 (0%) 0 (0%) 1 (0.2%) Marital status 0.697 Single 14 (36.8%) 18 (47.4%) 6 (15.8%) 38 (8.8%) Married/living with a partner 132 (43.0%) 124 (40.4%) 51 (16.6%) 307 (70.7%) Separated/divorced 15 (40.5%) 18 (48.6%) 4 (10.8%) 37 (8.5%) Widow(er) 27 (51.9%) 17 (32.7%) 8 (15.4%) 52 (12.0%) Employment status <0.001* Member of a cooperative 2 (66.7%) 1 (33.3%) 0 (0%) 3 (0.7%) Employer with employees 3 (30.0%) 5 (50.0%) 2 (20.0%) 10 (2.3%) Self-employed or employer with no employees 5 (26.3%) 12 (63.2%) 2 (10.5%) 19 (4.4%) Working for the family company/business 1 (20.0%) 4 (80.0%) 0 (0%) 5 (1.2%) Public sector employee 8 (25.0%) 14 (43.8%) 10 (31.2%) 32 (7.4%) Private sector employee 29 (35.5%) 52 (59.1%) 7 (7.95%) 88 (20.3%) Unemployed 11 (35.5%) 12 (38.7%) 8 (25.8%) 31 (7.1%) On furlough 1 (100%) 0 (0%) 0 (0%) 1 (0.2%) Retired 117 (53.9%) 67 (30,9%) 33 (15.2%) 217 (50.0%) Other 11 (39.3%) 10 (35.7%) 7 (25.0%) 28 (6.5%) Dependents 0.005 Children (under 14 years of age) 15 (27.8%) 29 (53.7%) 10 (18.5%) 54 (12.4%) Person with physical and/or mental disability > 60 years old 19 (37.3%) 17 (33.3%) 15 (29.4%) 51 (11.8%) None 154 (46.8%) 131 (39.8%) 44 (13.4%) 329 (75.8%) Bonet‑Esteve et al. BMC Fam Pract (2021) 22:84 Page 5 of 9 Table 3 Vaccination intention according to perception of risk of catching influenza, number of risk factors and vaccination history Perception of risk of dependents catching influenza 0.034 Yes 15 (44.1%) 9 (26.5%) 10 (29.4%) 34 (32.38%) No 15 (30.6%) 27 (55.1%) 7 (14.3%) 49 (46.66%) DK/NO 4 (18.2%) 10 (45.5%) 8 (36.4%) 22 (20.9%) Perception of the risk of personally catching influenza <0.001 Yes 88 (71.0%) 18 (14.5%) 18 (14.5%) 124 (28.6%) No 52 (25.6%) 121 (59.6%) 30 (14.8%) 203 (46.8%) DK/NO 48 (44.9%) 38 (35.5%) 21 (19.6%) 107 (24.7%) No. of risk factors (including age) <0.001 2.23 (1.26) 1.51 (0.92) 1.64 (1.03) 1.84 (1.14) No. of risk factors (not including age) N=41 N=82 N=28 N=151 0.070 1.34 (0.57) 1.11 (0.44) 1.25 (0.70) 1.20 (0.542) Vaccinated the previous year < 0.001 Yes 138 (89.0%) 3 (1.94%) 14 (9.03%) 155 (35.7%) No 47 (17.1%) 174 (63.3%) 54 (19.6%) 275 (63.4%) DK/NO 3 (75.0%) 0 (0%) 1 (25.0%) 4 (0.9%) Vaccinated on other occasions <0.001 Yes 149 (69.0%) 35 (16.2%) 32 (14.8%) 216 (49.8%) No 39 (17.9%) 142 (65.1%) 37 (17.0%) 218 (50.2%) DK/NO 0 (0%) 0 (0%) 0 (0%) 0 (0%) One hundred and eighty-eight (43.3%) participants response Don’t Know/No Opinion was chosen by 20% of reported intention to be vaccinated against influenza this the participants. season, 177 (40.8%) had no intention to be vaccinated Those under 60 years of age expressed a significantly and 69 (15.9%) did not know yet or did not answer. When lower intention to be vaccinated than those over 60 asked if they intended to be vaccinated against influenza years of age (p <0.001). Retired participants were more due to the context of d the SARS-CoV-2 pandemic, 212 in favour of being vaccinated compared with those (48.8%) answered that they did, 34 (7.8%) of whom would actively working (p <0.001). Living with dependents do so due to the pandemic and 178 (41.0%) intended to (children and adult dependents) was strongly associated receive the vaccine regardless the context. However, with the intention to vaccinate (p <0.005). The inten- 71 (16.4%) were hesitant or didn’t answer the question tion to vaccinate was also related to the perception of (Table 4). Of all those who intended to be vaccinated the risk of catching influenza (p <0.001) and to the per- against influenza, 14.9% would do it due to the pandemic. ceived risk for transmission to dependent individuals (p Regarding vaccination intention and the relationship = 0.03). Those with lower levels of education were more with the protective measures put in place during the inclined to be vaccinated than those with higher educa- pandemic, 156 (36.6%) reported they will be vaccinated tion (p = 0.016). despite wearing face masks and 47 (10.8%) said they won’t Having risk factors, excluding age, was not associated do so because they believe that masks already protected with vaccination intention (p = 0.07). With regard to an them. Regarding hand washing and physical distancing, individual’s history of influenza vaccinations, the inten- 162 (37.3%) and 157 (36.2%) respondents respectively tion to vaccinate this year was associated with having stated that they will be vaccinated despite following these been vaccinated the previous year and on another earlier measures. Fifty participants (11.5%) do not intend to season (p<0.001). Neither gender, nationality, nor mari- be vaccinated because they believed that hand washing tal status showed statistically significant differences with already protected them and 56 (12.9%) said they won’t be respect to the respondents’ intention to vaccinate. How- vaccinated due to the protection afforded by physical dis- ever, a relationship was found with their level of educa- tancing. Aproximately 25% of respondents had no inten- tion and employment status. tion of getting vaccinated despite acknowledging that The best logistic regression model for predicting the none of the three measures protected them. Regarding intention to vaccinate took into account just two varia- the questions related to the three contextual variables, the bles: the subject’s perception of whether they would catch influenza and whether or not they had been vaccinated Bonet‑Esteve et al. BMC Fam Pract (2021) 22:84 Page 6 of 9 Table 4 Vaccination intention in light of the SARS-CoV-2 pandemic COVID-19 pandemic and vaccination intention < 0.001 Yes, regardless of the COVID-19 pandemic 154 (86.5%) 17 (9.55%) 7 (3.93%) 178 (41.0%) Yes, due to the COVID-19 pandemic 27 (79.4%) 1 (2.94%) 6 (17.6%) 34 (7.8%) No, in spite of the COVID-19 pandemic 0 (0%) 32 (97.0%) 1 (3.03%) 33 (7.6%) No, regardless of the COVID-19 pandemic 4 (3.39%) 111 (94.1%) 3 (2.54%) 118 (27.2%) DK/NO 3 (4.23%) 16 (22.5%) 52 (73.2%) 71 (16.4%) Mask usage and vaccination intention <0.001 I will get vaccinated, even though masks offer protection, 151 (95.0%) 1 (0.63%) 7 (4.40%) 159 (36.6%) I will get vaccinated as masks don’t offer protection 28 (93.3%) 0 (0%) 2 (6.67%) 30 (6.9%) Masks don’t offer protection, but I won’t get vaccinated 0 (0%) 110 (99.1%) 1 (0.90%) 111 (25.6%) Masks offer protection, which is why I won’t get vaccinated 2 (4.26%) 44 (93.6%) 1 (2.13%) 47 (10.8%) DK/NO 7 (8.05%) 22 (25.3%) 58 (66.7%) 87 (20.0%) Hand washing and vaccination intention <0.001 I will get vaccinated, even though hand washing offers protection. 154 (95.1%) 1 (0.62%) 7 (4.32%) 162 (37.3%) I will get vaccinated as hand washing doesn’t offer protection 24 (88.9%) 0 (0%) 3 (11.1%) 27 (6.2%) I won’t get vaccinated, even though hand washing doesn’t offer protection 0 (0%) 106 (98.1%) 2 (1.85%) 108 (24.9%) I won’t get vaccinated as hand washing offers protection 1 (2.0%) 49 (98.0%) 0 (0%) 50 (11.5%) DK/NO 9 (10.3%) 21 (24.1%) 57 (65.5%) 87 (20.0%) Physical distancing and vaccination intention < 0.001 Social distancing offers protection, I will get vaccinated 152 (96.8%) 0 (0%) 5 (3.18%) 157 (36.2%) Social distancing doesn’t offer protection, which is why I will get vaccinated 24 (80.0%) 1 (3.33%) 5 (16.7%) 30 (6.9%) Social distancing doesn’t offer protection, nevertheless, I won’t get vaccinated 1 (0.98%) 99 (97.1%) 2 (1.96%) 102 (23.5%) Social distancing offers protection, which is why I will get vaccinated 1 (1.79%) 55 (98.2%) 0 (0%) 56 (12.9%) DK/NO 10 (11.2%) 22 (24.7%) 57 (64.0%) 89 (20.5%) the previous year, obtaining results with a predictive population group. This makes the study of great value accuracy of 87.7% (Table 5). when planning actions aimed at improving SIV cover- age in our area. Discussion The results show that the percentage of individuals who During the current SARS-CoV-2 pandemic, the 2020- intend to get vaccinated against influenza is similar to 21 Seasonal Influenza Vaccine campaign was per- those who do not intend to do so, though there are also ceived to be influenced by a lack of knowledge as to the a large number of individuals who remain undecided with behaviour of the influenza virus and uncertainty as to regard to this year’s influenza vaccination. Therefore, there the degree of acceptance of SIV by the at-risk popula- is the potential for promoting health education among tion. The health authorities have promoted increased the vaccine hesitant or undecided, if we take into account SIV coverage, especially among the elderly and oth- that, according to Picazo [17], almost 50% of these who are ers with risk factors, to protect them and thus to also undecided would be willing to get the vaccine if appro- reduce the strain on the healthcare system [6, 9]. This priately explained. Several studies show the possibility of study provides data on influenza vaccination intention improving vaccine coverage through educational initia- and the factors which influence the intention in this tives aimed at individuals who refuse vaccines [18, 19]. Table 5 Information on the logistic regression model for vaccination intention in light of the SARS-CoV-2 pandemic as a response variable Estimated beta Standard deviation Odds-Ratio IC 95% P-value coefficient Intercept 4.709 - - - - - Feel they will catch the influenza = NO -1.866 0.460 0.155 0.062 0.377 <0.001 Feel they will catch the influenza = DK/NO -1.281 0.520 0.278 0.097 0.757 0.014 Vaccinated last year = NO -4.631 0.621 0.010 0.002 0.028 <0.001 Vaccinated last year = DK/NO 13.078 1328.368 478084.231 - - 0.992 Bonet‑Esteve et al. BMC Fam Pract (2021) 22:84 Page 7 of 9 According to a WHO review of barriers to influenza the prioritization of virtual and telephone visits and the vaccination [11] there are no conclusive data linking age development of influenza vaccination campaigns in dif- and vaccine coverage, although this study, along with ferent spaces, outside the confines of health centres [6]. some others [20], suggests that the elderly are more likely The lower degree of interaction with the healthcare sys- to get vaccinated. Since everyone with risk factors is tem or the lack of specific and direct advice from a pro- encouraged to be immunized against influenza, coverage fessional regarding vaccination appears to be related to would be expected to be high [20]. Nevertheless, vaccine the coverage achieved [11]. It remains to be seen how this coverage achieved in previous campaigns [1] together limitation may have influenced the vaccine hesitancy and with the data on vaccination intention in our study show the management of indecision or doubts regarding vac- that younger people are less vaccinated and have lower cination this year. vaccination intentions. With regard to the intention to be vaccinated against A low perception of the risk of influenza is a major bar- influenza this year during the SARS-CoV-2 pandemic, we rier to vaccination [13]. The study shows that about half found that an additional 5% coverage could be achieved of the respondents have a low perception of the risk of with respect to the intention to vaccinate without con- influenza and, in line with other studies [11, 15], this sidering this factor (question 12), a lower figure than low perception is associated with the intention to refuse that of the Goldman study, estimated at 10% [13]. It is being vaccinated. Half of those surveyed with dependents known that a negative attitude towards the influenza at their care believe there is no risk for their dependents vaccine is associated with lower vaccination rates [11] as to being infected with influenza virus and more than and in this study it is noteworthy that, despite the ongo- half of this group refuse the vaccine. This fact reveals lack ing pandemic, more than a third (34.8%) of respondents of information about the disease, its chains of infections reported that they would not be vaccinated regardless. and the possible complications which make the vaccina- These data would suggest a lack of awareness among the tion necessary. As some studies point out, lack of aware- population regarding influenza, SARS-CoV-2 and their ness, misconceptions and knowledge gaps are the main complications. They may also lack information regard- barriers to influenza vaccination [10, 11]. ing the risk of coinfection which, although such cases are In line with other studies, vaccination intention for the rare, carry an increased risk for patients suffering from current season is high in people who were vaccinated the both infections. Hence the health authorities’ preoccupa- previous season [11, 20]. This fact shows that a history tion with actively encouraging influenza vaccinations this of previous influenza vaccination is a predictor of vac- year. Recent evidence shows that mortality in patients cination in the current season, especially if it has been a with SARS-CoV-2 doubles when they are also infected positive experience. With regard to those not vaccinated with the influenza virus [21]. in the previous year, it is worth noting a considerable According to a Cochrane review [22] on the effective- increase in the percentage of individuals intending to be ness of simple physical barriers in reducing the spread of vaccinated this year. There was also a significant number respiratory viruses, frequent hand washing can reduce of hesitant patients , in keeping with the findings of the the transmission of respiratory viruses; isolation and Goldman study [13]. physical barriers (wearing masks, gloves and gowns) did The logistical model to predict an individual’s vaccina- not show a clear reduction in respiratory viral infection; tion intention shows that, both the perception of catch- and there is insufficient evidence to show that physical ing influenza oneself and an individual’s vaccination distancing can reduce the spread of viruses. The results history for the previous year are variables which favour show that with regard to physical protection measures influenza vaccination coverage, in line with earlier stud- (masks, hand washing and spatial separation), more ies [11, 13, 20]. It can be seen that for levels where the than 35% of the surveyed population would be willing response is negative or "Don’t know/No Opinion", a neg- to be vaccinated even though they believe that the bar- ative relationship is maintained with the response to the rier already protects them. That is, they are individuals vaccination intention variable. It is also noteworthy that who most likely already receive the seasonal influenza the "Don’t know/No Opinion" responses regarding vacci- shot and who are not making an exception because of nation in the previous year are insignificant, being almost the pandemic. Meanwhile, it is significant that more than zero. This should be taken into account in future predic- 10% of the participants believe that these three meas- tions if the same model is used. ures already protect them and therefore do not intend The recent pandemic has meant that users’ face- to be vaccinated. Finally, a significant percentage of par- to-face access to health services and communication ticipants expressed doubts regarding the intention to be with health professionals has been impaired. However, vaccinated against influenza during the pandemic and organizational changes have been implemented such as the protection offered by contextual factors. Preventive Bonet‑Esteve et al. BMC Fam Pract (2021) 22:84 Page 8 of 9 measures are effective as they are taken together rather Abbreviations SIV: Seasonal Influenza Vaccine; WHO: World Health Organisation; ECDC: than being mutually exclusive or implemented indepen- European Centre for Disease Prevention and Control; PCT: Primary Care dently. That is why in these groups it is important to teams; IDIAP: University Institut for Primary Care Research (Institut Universitari improve the information to achieve a change in attitude d’Investigació en Atenció Primària. regarding the acceptance of vaccination. Therefore, although the intention to vaccinate group Supplementary Information is not much larger than the non-intention group, there The online version contains supplementary material available at https://​doi.​ org/​10.​1186/​s12875-​021-​01434-8. are many undecided individuals, possibly due to a lack of information, misconceptions or doubts, as in other stud- ies [10]. Although not everyone is expected to change Additional file 1. Questionnaire. their vaccination intention and to go on to be vaccinated, it is necessary that medical professionals take the time to Acknowledgements We would like to thank Marisa Serra, Esperanza Solà, Judit Torrent and Lor‑ uncover their doubts and reluctance regarding vaccina- ena Vázquez for their support with the survey interviews. tion, in order to be able to provide them with accurate information and help them make an informed decision Authors’ contributions ABE, RMM, CGC, AR and JVA contributed to the conceptualization, study [23]. A recent published paper of our group showed that design, data collection and writing of the article. XP contributed to the data a brief intervention could be an effective tool in improv- analysis and writing of the article. All of the authors reviewed and approved ing vaccination coverage in reluctant people [24]. the article prior to its publication. This study may present certain limitations. The find- Funding ing of the study may not be totally generalizable as the None declared study has been conducted in a specific region of Spain. Availability of data and materials It did not include individuals who had not given their Our manuscript is based on confidential and sensitive healthcare data. However, consent to be contacted for healthcare and research pur- to support scientific transparency, we have posted a de-identified and appropri‑ poses; this may have led to a certain selection bias, which ately redacted data for replication purposes should you or the reviewers find it helpful. The data is available at the review stage for the journal staff and review‑ we attempted to minimize through the randomization ers at our Mendeley data repository http://​dx.​doi.​org/​10.​17632/​9b4b4​3tr9k.1 of participants. Although the questionnaire employed had been adapted from a previous one, some questions, Declarations especially those related to the intention to vaccinate dur- ing the SARS-CoV-2 pandemic, had very similar answer Ethics approval and consent to participate All data extracted were anonymized and treated as strictly confidential. All meth‑ options which could generate doubts and be difficult to ods were performed in accordance with the Declaration of Helsinki.The Research comprehend. A training session was held for the inter- Ethics Committee (CEI) of the Institut Universitari d’Investigació en Atenció viewers in order to control for these difficulties and avoid Primària (IDIAP Jordi Gol) approved the study protocol number 20/177-PCV.Verbal informed consent to participate was obtained from the participants previous to differences in the interpretation of the answers. the telephone survey (it can be read in the Additional file 1 Questionnaire). To continue with this line of research, the aim is to determine the relationship between vaccination inten- Consent for publication Not applicable tion with regard to influenza at the start of the vaccina- tion campaign and the number of influenza vaccinations Competing interests recorded at the end of the campaign in at-risk groups. The authors declare that they have no competing interests Author details 1 Unitat de Farmàcia, Gerència Territorial Catalunya Central Institut Català de la Conclusions Salut, Sant Fruitós de Bages, Spain. 2 Health Promotion in Rural Areas Research Group, Gerència Territorial de la Catalunya Central, Institut Català de la Salut, Vaccination intention can be a good predictor of people’s Sant Fruitós de Bages, Spain. 3 Centre d’Atenció Primària Plaça Catalunya, SAP future behaviour with regard to the influenza vaccina- Bages-Berguedà-Solsonès, Gerència Territorial Catalunya Central Institut Català tion, although during the SARS-CoV-2 pandemic many de la Salut, CAP Plaça Catalunya. C/ Soler i March 6, 08242 Manresa, Spain. 4 Centre d’Atenció Primària Vilanova del Camí, SAP Anoia, Gerència Territorial people are undecided, possibly due to a lack of knowl- Catalunya Central, Institut Català de la Salut, Vilanova del Camí, Spain. 5 Centre edge regarding influenza, its means of transmission and d’Atenció Primària Manlleu, SAP Osona, Gerència Territorial Catalunya Central, possible complications. This study highlights the need Institut Català de la Salut, Manlleu, Spain. 6 Universitat Autònoma de Barcelona, Barcelona, Spain. 7 Unitat de Suport a la Recerca de la Catalunya Central, Fun‑ to strengthen health education regarding the influenza dació Institut Universitari per a la recerca a l’Atenció Primària de Salut Jordi Gol vaccination in at- risk groups, especially in those who i Gurina, Sant Fruitós de Bages, Spain. 8 Faculty of Medicine, University of Vic - express vaccine hesitancy. Central University of Catalonia, Vic, Spain. 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Determinants of adults’ intention to vaccinate against pandemic swine flu. BMC Public Health. 2011;11:1–5. https://​doi.​ Publisher’s Note org/​10.​1186/​1471-​2458-​11-​15. Springer Nature remains neutral with regard to jurisdictional claims in pub‑ 13 Goldman R, McGregor S, Shashidar M, Katsuta T, Griffiths M, Hall J, et al. lished maps and institutional affiliations. Willingness to vaccinate Children against Influenza after the COVID-19 Ready to submit your research ? Choose BMC and benefit from: • fast, convenient online submission • thorough peer review by experienced researchers in your field • rapid publication on acceptance • support for research data, including large and complex data types • gold Open Access which fosters wider collaboration and increased citations • maximum visibility for your research: over 100M website views per year At BMC, research is always in progress. Learn more biomedcentral.com/submissions