SARS-CoV-2 Seroprevalence and Antibody Kinetics Among Health Care Workers in a Spanish Hospital After 3 Months of Follow-up.

BACKGROUND: At the COVID-19 spring 2020 pandemic peak in Spain, prevalence of SARS-CoV-2 infection in a cohort of 578 randomly selected health care workers (HCWs) from Hospital Clínic de Barcelona was 11.2%. METHODS: A follow-up survey 1 month later (April-May 2020) measured infection by rRT-PCR and IgM, IgA, and IgG to the receptor-binding domain of the spike protein by Luminex. Antibody kinetics, including IgG subclasses, was assessed until month 3. RESULTS: At month 1, the prevalence of infection measured by rRT-PCR and serology was 14.9% (84/565) and seroprevalence 14.5% (82/565). We found 25 (5%) new infections in 501 participants without previous evidence of infection. IgM, IgG, and IgA levels declined in 3 months (antibody decay rates 0.15 [95% CI, .11-.19], 0.66 [95% CI, .54-.82], and 0.12 [95% CI, .09-.16], respectively), and 68.33% of HCWs had seroreverted for IgM, 3.08% for IgG, and 24.29% for IgA. The most frequent subclass responses were IgG1 (highest levels) and IgG2, followed by IgG3, and only IgA1 but no IgA2 was detected. CONCLUSIONS: Continuous and improved surveillance of SARS-CoV-2 infections in HCWs remains critical, particularly in high-risk groups. The observed fast decay of IgA and IgM levels has implications for seroprevalence studies using these isotypes.

Exploring women's experiences of participation in shared decision-making during childbirth: a qualitative study at a reference hospital in Spain.

BACKGROUND: Women's engagement in healthcare decision-making during childbirth has been increasingly emphasised as a priority in maternity care, since it increases satisfaction with the childbirth experience and provides health benefits for women and newborns. The birth plan was developed as a tool to facilitate communication between health professionals and women in Spain, but their value in routine practice has been questioned. Besides, little is known about women's experiences of participation in decision-making in the Spanish context. Thus, this study aimed to explore women's experiences of participation in shared decision-making during hospital childbirth. METHODS: An exploratory qualitative study using focus groups was carried out in one maternity unit of a large reference hospital in Barcelona, Spain. Participants were first-time mothers aged 18 years or older who had had a live birth at the same hospital in the previous 12 months. Data collected were transcribed verbatim and analysed using a six-phase inductive thematic analysis process. RESULTS: Twenty-three women participated in three focus groups. Three major themes emerged from the data: "Women's low participation in shared decision-making", "Lack of information provision for shared decision-making", and "Suggestions to improve women's participation in shared decision-making". The women who were willing to take an active role in decision-making encountered barriers to achieving this and some women did not feel prepared to do so. The birth plan was experienced as a deficient method to promote women's participation, as health professionals did not use them. Participants described the information given as insufficient and not offered at a timely or useful point where it could aid their decision-making. Potential improvements identified that could promote women's participation were having a mutually respectful relationship with their providers, the support of partners and other members of the family and receiving continuity of a coordinated and personalised perinatal care. CONCLUSION: Enhancing women's involvement in shared decision-making requires the acquisition of skills by health professionals and women. The development and implementation of interventions that encompass a training programme for health professionals and women, accompanied by an effective tool to promote women's participation in shared decision-making during childbirth, is highly recommended.

Educating on professional habits: attitudes of medical students towards diverse strategies for promoting influenza vaccination and factors associated with the intention to get vaccinated.

BACKGROUND: Influenza vaccination coverage in medical students is usually low. Unlike health care workers, there is little information on the attitudes to and predictors of vaccination among medical students, and their attitudes towards institutional strategies for improving rates are unknown. METHODS: This cross-sectional study evaluated the effect of three influenza vaccination promotional strategies (Web page, video and tri-fold brochure) on medical students' intention to get vaccinated and associated factors. A total of 538 medical students were asked to answer an anonymous questionnaire assessing the intention to get vaccinated after exposure to any of the promotional strategies. Sociodemographic data collected included: sex, age, university year, influenza risk group and cohabiting with member of a risk group. RESULTS: Four hundred twenty-one students answered the questionnaire, of whom 312 (74.1%) were female, 113 (26.8%) had done clinical rotations, and 111 (26.6%) reported intention to get the flu shot. Logistic regression showed the web group had a greater intention to get vaccinated than the reference group (OR: 2.42 95% CI: 1.16-5.03). Having done clinical rotations (OR: 2.55 95% CI: 1.36-4.38) and having received the shot in previous flu seasons (OR: 13.69 95% CI: 7.86-23.96) were independently associated with the intention to get vaccinated. CONCLUSION: Given that previous vaccination is a factor associated with the intention to get vaccinated, education on vaccination of health care workers should begin while they are students, thereby potentiating the habit. In addition, the intention to get vaccinated was greater during the clinical phase of the university career, suggesting this is a good time to introduce promotion strategies. Online promotional campaigns, such as a thematic Web to promote vaccination of health workers, could improve the intention to get vaccinated.

Maternal educational level and preterm birth: Exploring inequalities in a hospital-based cohort study.

Preterm birth has been related to inequalities in maternal educational level, but the causal mechanism is not entirely known. Some factors associated with preterm birth and low educational level such as chronic medical conditions, pregnancy complications and related-health behaviours could have a mediation role in the pathway. This study aimed to evaluate the association between maternal educational level and preterm birth, analysing the mediation role of these factors. We performed a retrospective cohort study based on hospital electronic records of 10467 deliveries that took place in the Hospital Clínic of Barcelona between 2011 and 2017. Poisson regression was used to obtain crude and adjusted relative risk of preterm birth in women with different educational level and the percentage of change in relative risk was calculated when mediation variables were included in the model. Women with a lower educational level had a higher risk of preterm birth (RR 1.57, 95% CI 1.21, 2.03). The loss of association after the inclusion of body mass index in the model suggests an important mediation role of maternal overweight. Other variables such as smoking, drug use, preeclampsia and genitourinary infections also appear to play a role in the observed inequality between women with different levels of education. Efforts to promote health literacy and to improve preventive interventions, before and during pregnancy, could decrease preterm birth rates and perinatal health inequalities.

Factors related to inhibition of lactation by pharmacological means at birth in a Spanish referral hospital (2011-2017).

OBJECTIVE: To describe the maternal, neonatal and pregnancy characteristics related to inhibition of lactation (IL) with cabergoline. METHOD: We assessed 20,965 occasions of breastfeeding initiation, according to data collected from obstetric records at the Hospital Clinic of Barcelona (Spain) between January 2011 and December 2017. RESULTS: IL decreased over the study period from 8.78% to 6.18% (odds ratio [OR]: 0.93 per year; 95% confidence interval [95%CI]: 0.90-0.95). Women with a lower educational level (OR: 2.5; 95%CI: 2.0-3.0), mothers living in more depressed areas (OR: 1.08 per 10 extra points over 100; 95%CI: 1.04-1.12), smokers (OR: 2.2; 95%CI: 1.9-2.6), and those with more children (OR: 1.2 for each sibling; 95%CI: 1.1-1.3), preterm birth (OR: 1.8; 95%CI: 1.4-2.3), multiple births (OR: 1.6; 95%CI: 1.2-2.1) and a higher risk pregnancy (OR: 1.3 per risk point; 95%CI: 1.2-1.4) showed a higher prevalence of IL. Compared to women born in Spain, IL was less likely in all other women with the exception of Chinese women (OR: 7.0; 95%CI: 5.7-8.6). These disparities remained during the study period. CONCLUSIONS: Factors related to lower socioeconomic status and poor health were more likely to be associated with IL. The overall use of cabergoline decreased during the study period while inequalities persisted. Taking these inequalities into account is the first step to addressing them.

"Maternal Vaccination Greatly Depends on Your Trust in the Healthcare System": A Qualitative Study on the Acceptability of Maternal Vaccines among Pregnant Women and Healthcare Workers in Barcelona, Spain.

The World Health Organization (WHO) identified vaccine hesitancy as one of the top 10 threats to global health in 2019. Health promotion and education have been seen to improve knowledge and uptake of vaccinations in pregnancy. This qualitative study was conducted based on phenomenology, a methodological approach to understand first-hand experiences, and grounded theory, an inductive approach to analyse data, where theoretical generalisations emerge. Data were collected through semi-structured interviews with pregnant women attending antenatal care services and healthcare workers (HCWs) in Barcelona, Spain. Interviews were audio-recorded, transcribed, and coded, and notes were taken. Inductive thematic analysis was performed, and data were manually coded. Pertussis was reported as the most trusted vaccine among pregnant women due to its long-standing background as a recommended vaccine in pregnancy. The influenza vaccine was regarded as less important since it was perceived to cause mild disease. The COVID-19 vaccine was the least trustworthy for pregnant women due to uncertainties about effectiveness, health effects in the mid- and long-term, the fast development of the vaccine mRNA technology, and the perceptions of limited data on vaccine safety. However, the necessity to be vaccinated was justified by pregnant women due to the exceptional circumstances of the COVID-19 pandemic. The recommendations provided by HCW and the established relationship between the HCW, particularly midwives, and pregnant women were the main factors affecting decision-making. The role of mass media was perceived as key to helping provide reliable messages about the need for vaccines during pregnancy. Overall, vaccines administered during pregnancy were perceived as great tools associated with better health and improved quality of life. Pregnancy was envisioned as a vulnerable period in women's lives that required risk-benefits assessments for decision-making about maternal vaccinations. A holistic approach involving the community and society was considered crucial for health education regarding maternal vaccines in support of the work conducted by HCWs.

Perceptions of COVID-19 Maternal Vaccination among Pregnant Women and Healthcare Workers and Factors That Influence Vaccine Acceptance: A Cross-Sectional Study in Barcelona, Spain.

COVID-19 is associated with poor maternal and pregnancy outcomes. COVID-19 vaccination is recommended in Spain, yet vaccination rates in pregnancy are suboptimal. This study investigates the perceptions of pregnant women and healthcare workers (HCW) regarding COVID-19 vaccination. A web-based cross-sectional quantitative study was conducted in 2021-2022 among 302 pregnant women and 309 HCWs in the Catalan public health system. Most pregnant women (83%) and HCWs (86%) were aware of COVID-19 maternal vaccines. The recommendation of the COVID-19 vaccination by an HCW was identified as the greatest facilitator for maternal vaccine uptake, while the fear of harming the foetus was the most significant barrier reported for rejecting vaccination. HCWs recognised they received limited information and training about COVID-19 vaccination in pregnancy, which hindered them from providing informed recommendations. This study highlights that information and education on COVID-19 vaccines to pregnant women and health professionals are pivotal to ensuring informed decision-making and increasing vaccine uptake.

HPV Vaccination in Women with Cervical Intraepithelial Neoplasia Undergoing Excisional Treatment: Insights into Unsolved Questions.

Several questions regarding the role of vaccination in women treated for high-grade cervical intraepithelial lesion (HSIL) have not been clarified. One of the main queries is whether the time at which the vaccine is administered (before or after treatment) influences the protection against post-treatment HSIL. A second unanswered question is whether the vaccine has any effect in women with persistent HPV after treatment. We aimed to address these questions in a study of 398 women undergoing excisional treatment from July 2016 to December 2019. Vaccination was funded and offered to all women undergoing treatment. A total of 306 women (76.9%) accepted HPV vaccination (vaccinated group): 113 (36.9%) received the first dose before excision and 193 (63.1%) after the procedure. A total of 92 women (23.1%) refused the vaccine (non-vaccinated group). Women vaccinated before treatment showed a lower rate of post-treatment HSIL compared with non-vaccinated women (0.9% vs. 6.5%; p = 0.047). Among women with persistent HPV infection after treatment, those who had received the vaccine showed a lower prevalence of post-treatment HSIL than non-vaccinated women (2.6% vs. 10.5%; p = 0.043). In conclusion, this study shows that HPV vaccination before treatment reduces the prevalence of post-treatment HSIL and suggests that vaccination might even benefit women with persistent HPV after treatment.

SARS-CoV2 hospital surveillance and control system with contact tracing for patients and health care workers at a large reference hospital in Spain during the first wave: An observational descriptive study.

BACKGROUND AND AIMS: During the first peak of the COVID-19 pandemic, the Preventive Medicine Department and the Occupational Health Department at Hospital Clinic de Barcelona (HCB), a large Spanish referral hospital, developed an innovative comprehensive SARS-CoV2 Surveillance and Control System (CoSy-19) in order to preserve patients' and health care workers' (HCWs) safety. We aim to describe the CoSy-19 and to assess the impact in the number of contacts that new cases generated along this time. METHODS: Observational descriptive study of the findings of the activity of contact tracing of all cases received at the HCB during the first peak of COVID-19 in Spain (February 25th-May 3rd, 2020). RESULTS: A team of 204 professionals and volunteers performed 384 in-hospital contact-tracing studies which generated contacts, detecting 298 transmission chains which suggested preventive measures, generated around 22 000 follow-ups and more than 30 000 days of work leave. The number of contacts that new cases generated decreased during the study period. CONCLUSION: Coordination between Preventive Medicine and Occupational Health departments and agile information systems were necessary to preserve non-COVID activity and workers safety.

Determinants of early antibody responses to COVID-19 mRNA vaccines in a cohort of exposed and naïve healthcare workers.

BACKGROUND: Two doses of mRNA vaccination have shown >94% efficacy at preventing COVID-19 mostly in naïve adults, but it is not clear if the second dose is needed to maximize effectiveness in those previously exposed to SARS-CoV-2 and what other factors affect responsiveness. METHODS: We measured IgA, IgG and IgM levels against SARS-CoV-2 spike (S) and nucleocapsid (N) antigens from the wild-type and S from the Alpha, Beta and Gamma variants of concern, after BNT162b2 (Pfizer/BioNTech) or mRNA-1273 (Moderna) vaccination in a cohort of health care workers (N=578). Neutralizing capacity and antibody avidity were evaluated. Data were analyzed in relation to COVID-19 history, comorbidities, vaccine doses, brand and adverse events. FINDINGS: Vaccination induced robust IgA and IgG levels against all S antigens. Neutralization capacity and S IgA and IgG levels were higher in mRNA-1273 vaccinees, previously SARS-CoV-2 exposed, particularly if symptomatic, and in those experiencing systemic adverse effects (p<0·05). A second dose in pre-exposed did not increase antibody levels. Smoking and comorbidities were associated with 43% (95% CI, 19-59) and 45% (95% CI, 63-18) lower neutralization, respectively, and 35% (95% CI, 3-57%) and 55% (95% CI, 33-70%) lower antibody levels, respectively. Among fully vaccinated, 6·3% breakthroughs were detected up to 189 days post-vaccination. Among pre-exposed non-vaccinated, 90% were IgG seropositive more than 300 days post-infection. INTERPRETATION: Our data support administering a single-dose in pre-exposed healthy individuals as primary vaccination. However, heterogeneity of responses suggests that personalized recommendations may be necessary depending on COVID-19 history and life-style. Higher mRNA-1273 immunogenicity would be beneficial for those expected to respond worse to vaccination and in face of variants that escape immunity such as Omicron. Persistence of antibody levels in pre-exposed unvaccinated indicates maintenance of immunity up to one year. FUNDING: This work was supported by Institut de Salut Global de Barcelona (ISGlobal) internal funds, in-kind contributions from Hospital Clínic de Barcelona, the Fundació Privada Daniel Bravo Andreu, and European Institute of Innovation and Technology (EIT) Health (grant number 20877), supported by the European Institute of Innovation and Technology, a body of the European Union receiving support from the H2020 Research and Innovation Programme. We acknowledge support from the Spanish Ministry of Science and Innovation and State Research Agency through the "Centro de Excelencia Severo Ochoa 2019-2023" Program (CEX2018-000806-S), and support from the Generalitat de Catalunya through the CERCA Program. L. I. work was supported by PID2019-110810RB-I00 grant from the Spanish Ministry of Science & Innovation. Development of SARS-CoV-2 reagents was partially supported by the National Institute of Allergy and Infectious Diseases Centers of Excellence for Influenza Research and Surveillance (contract number HHSN272201400008C). The funders had no role in study design, data collection and analysis, the decision to publish, or the preparation of the manuscript.

SARS-CoV-2 transmission in students of public schools of Catalonia (Spain) after a month of reopening.

INTRODUCTION: SARS-CoV-2 transmission within schools and its contribution to community transmission are still a matter of debate. METHODS: A retrospective cohort study in all public schools in Catalonia was conducted using publicly available data assessing the association between the number of reported SARS-CoV-2 cases among students and staff in weeks 1-2 (Sept 14-27th, 2020) of the academic year with school SARS-CoV-2 incidence among students in weeks 4-5. A multilevel Poisson regression model adjusted for the community incidence in the corresponding basic health area (BHA) and the type of school (primary or secondary), with random effects at the sanitary region and BHA levels, was performed. RESULTS: A total of 2184 public schools opened on September 14th with 778,715 students. Multivariate analysis showed a significant association between the total number of SARS-CoV-2 cases in a centre in weeks 1-2 and the SARS-CoV-2 school incidence among students in weeks 4-5 (Risk Ratio (RR) 1.074, 95% CI 1.044-1.105, p-value <0.001). The adjusted BHA incidence in the first two weeks was associated with school incidence in weeks 4-5 (RR 1.002, 95% CI 1.002-1.003, p-value <0.001). Secondary schools showed an increased incidence in weeks 4 and 5 (RR primary vs secondary 1.709 95% CI 1.599-1.897, p-value <0.001). CONCLUSIONS: Safety measures adopted by schools were not enough to stop related-to-school transmission in students and could be improved. The safest way to keep schools open is to reduce community transmission down to a minimum.

Seven-month kinetics of SARS-CoV-2 antibodies and role of pre-existing antibodies to human coronaviruses.

Unraveling the long-term kinetics of antibodies to SARS-CoV-2 and the individual characteristics influencing it, including the impact of pre-existing antibodies to human coronaviruses causing common cold (HCoVs), is essential to understand protective immunity to COVID-19 and devise effective surveillance strategies. IgM, IgA and IgG levels against six SARS-CoV-2 antigens and the nucleocapsid antigen of the four HCoV (229E, NL63, OC43 and HKU1) were quantified by Luminex, and antibody neutralization capacity was assessed by flow cytometry, in a cohort of health care workers followed up to 7 months (N = 578). Seroprevalence increases over time from 13.5% (month 0) and 15.6% (month 1) to 16.4% (month 6). Levels of antibodies, including those with neutralizing capacity, are stable over time, except IgG to nucleocapsid antigen and IgM levels that wane. After the peak response, anti-spike antibody levels increase from ~150 days post-symptom onset in all individuals (73% for IgG), in the absence of any evidence of re-exposure. IgG and IgA to HCoV are significantly higher in asymptomatic than symptomatic seropositive individuals. Thus, pre-existing cross-reactive HCoVs antibodies could have a protective effect against SARS-CoV-2 infection and COVID-19 disease.

Seroprevalence of antibodies against SARS-CoV-2 among health care workers in a large Spanish reference hospital.

Health care workers (HCW) are a high-risk population to acquire SARS-CoV-2 infection from patients or other fellow HCW. This study aims at estimating the seroprevalence against SARS-CoV-2 in a random sample of HCW from a large hospital in Spain. Of the 578 participants recruited from 28 March to 9 April 2020, 54 (9.3%, 95% CI: 7.1-12.0) were seropositive for IgM and/or IgG and/or IgA against SARS-CoV-2. The cumulative prevalence of SARS-CoV-2 infection (presence of antibodies or past or current positive rRT-PCR) was 11.2% (65/578, 95% CI: 8.8-14.1). Among those with evidence of past or current infection, 40.0% (26/65) had not been previously diagnosed with COVID-19. Here we report a relatively low seroprevalence of antibodies among HCW at the peak of the COVID-19 epidemic in Spain. A large proportion of HCW with past or present infection had not been previously diagnosed with COVID-19, which calls for active periodic rRT-PCR testing in hospital settings.

The social network around influenza vaccination in health care workers: a cross-sectional study.

BACKGROUND: Influenza vaccination coverage remains low among health care workers (HCWs) in many health facilities. This study describes the social network defined by HCWs' conversations around an influenza vaccination campaign in order to describe the role played by vaccination behavior and other HCW characteristics in the configuration of the links among subjects. METHODS: This study used cross-sectional data from 235 HCWs interviewed after the 2010/2011 influenza vaccination campaign at the Hospital Clinic of Barcelona (HCB), Spain. The study asked: "Who did you talk to or share some activity with respect to the seasonal vaccination campaign?" Variables studied included sociodemographic characteristics and reported conversations among HCWs during the influenza campaign. Exponential random graph models (ERGM) were used to assess the role of shared characteristics (homophily) and individual characteristics in the social network around the influenza vaccination campaign. RESULTS: Links were more likely between HCWs who shared the same professional category (OR 3.13, 95% CI = 2.61-3.75), sex (OR 1.34, 95% CI = 1.09-1.62), age (OR 0.7, 95% CI = 0.63-0.78 per decade of difference), and department (OR 11.35, 95% CI = 8.17-15.64), but not between HCWs who shared the same vaccination behavior (OR 1.02, 95% CI = 0.86-1.22). Older (OR 1.26, 95% CI = 1.14-1.39 per extra decade of HCW) and vaccinated (OR 1.32, 95% CI = 1.09-1.62) HCWs were more likely to be named. CONCLUSIONS: This study finds that there is no homophily by vaccination status in whom HCWs speak to or interact with about a workplace vaccination promotion campaign. This result highlights the relevance of social network analysis in the planning of health promotion interventions.

Factors associated with the immune response to hepatitis A vaccination in HIV-infected patients in the era of highly active antiretroviral therapy.

INTRODUCTION: HIV seropositivity is considered a risk factor for complications in hepatitis A virus (HAV) infection. HAV vaccination schedules are widely implemented in HIV-infected patients, but the immune response remains impaired. METHODS: We analysed the response to vaccination (antiHAV titres ≥20IU/l) in 282 HIV-infected patients included in a standard (1440 Elisa Units (EU) at 0, 6 months) or rapidly accelerated schedule (720 EU at 0, 7, 21 days and 6 months) between 1997 and 2009. Factors associated with the response to vaccination were analysed using logistic regression. RESULTS: The overall response rate was 73.4%. Male sex (OR: 0.16, 95% CI 0.05-0.51) and hepatitis C virus co-infection (OR: 0.30, 95% CI 0.14-0.74) were associated with a lower probability of response. Protective antibody response was associated with a higher CD4/CD8 ratio (OR: 3.69, 95% CI 1.3-10.5) and having received two doses of standard schedule (compared with patients receiving only one dose of the same schedule) (OR: 2.51, 95% CI 1.22-5.15). Three doses of the rapidly accelerated schedule were not more effective than a single dose of 1440 EU (OR: 1.32, 95% CI 0.48-3.63). CONCLUSION: The low responses observed in patients receiving a single dose suggest the need to emphasize adhesion to vaccination protocols to avoid failure. The CD4/CD8 ratio may be considered as an immune status marker which could help to better choose the moment of vaccination. Our findings underscore the importance of identifying strategies that optimize the timing and effectiveness of hepatitis A vaccination in HIV-infected patients and of the need for further studies on individual factors such as sex and hepatitis C co-infection that may affect the response to vaccination. Likewise, the sub-optimal effectiveness of three doses of 720 EU in the rapidly accelerated schedule, if confirmed in future studies, might lead to a revision of the current schedule recommended for HIV-infected travellers.

Evaluating influenza vaccination campaigns beyond coverage: a before-after study among health care workers.

BACKGROUND: Influenza vaccination campaigns based on educational interventions do not seem to increase coverage in the hospital setting, and their impact on educational goals is not usually evaluated. This study describes the campaign implemented in a university hospital and assesses the achievement of the strategic objectives, which were to increase health care workers (HCW) perceptions of the risk of influenza and of their role as promoters of influenza vaccination among their colleagues and to increase knowledge about influenza. METHODS: A before-after study was conducted using a self-administered survey in a randomized sample of HCW during the 2010-2011 influenza vaccination campaign. The Wilcoxon paired measures test was used to assess attainment of the strategic objectives. RESULTS: The campaign had a positive impact on the strategic objectives (Wilcoxon test, P value <.05 in all cases). The reach of the campaign was high (91.9%), and HCW rated it as positive (7.19 [standard deviation, 2.3] out of 10) but did not achieve increased coverage (34%; 95% confidence interval: 33.8-36.4). CONCLUSION: Evaluation of the campaign shows that its effect responded to the strategic objectives. However, it seems that increasing the information provided to HCW and heightening their risk perception do not necessarily lead to greater acceptance of influenza vaccination.

The willingness of medical students to use Facebook as a training channel for professional habits: the case of influenza vaccination.

The low acceptance of influenza vaccination by both medical students and healthcare workers (HCWs) signals the need for innovative strategies. We administered an anonymous questionnaire to 410 University of Barcelona medical students who were asked about using the Internet to find information on influenza vaccination of HCWs and about their willingness to use technical and informal Facebook pages as an information channel on this topic. Of the 410 participants, 74.1 percent were female and 58.3 percent were in the first preclinical 3-year university cycle. A total of 7.6 percent participants reported using the Internet for queries on influenza vaccination, 89.8 percent reported that they were Facebook users, and 275 (67.1 percent) would accept an invitation from the technical or informal Facebook pages. The technical Web site would be actively followed by 77, or by 30.0 percent of those who would accept the invitation and the informal site by 116 (43.6 percent of those who would accept). The marked willingness to use Facebook to obtain information on the influenza vaccination of HCWs potentially opens a new window in health education: social networks could be used to help create professional habits. Students would be more likely to engage with this type of Facebook page if the contents were informal rather than highly technical.