Influenza Vaccination Campaign Research Articles

COVID-19 Vaccination Strategies in the Endemic Period: Lessons from Influenza.

Coronavirus disease 2019 (COVID-19) is a highly contagious zoonotic respiratory disease with many similarities to influenza. Effective vaccines are available for both; however, rapid viral evolution and waning immunity make them virtually impossible to eradicate with vaccines. Thus, the practical goal of vaccination is to reduce the incidence of serious illnesses and death. Three years after the introduction of COVID-19 vaccines, the optimal vaccination strategy in the endemic period remains elusive, and health authorities worldwide have begun to adopt various approaches. Herein, we propose a COVID-19 vaccination strategy based on the data available until early 2024 and discuss aspects that require further clarification for better decision making. Drawing from comparisons between COVID-19 and influenza vaccination strategies, our proposed COVID-19 vaccination strategy prioritizes high-risk groups, emphasizes seasonal administration aligned with influenza vaccination campaigns, and advocates the co-administration with influenza vaccines to increase coverage.

Parents and teachers’ perspectives on a school-located influenza vaccination program: A pilot study in the Region of Murcia, Spain

ABSTRACT During the 2022–2023 season, the Region of Murcia (an autonomous community of Spain) introduced the influenza vaccination campaign in children aged 24–59 months with the live-attenuated influenza nasal spray vaccine. To expand coverage, a pilot study was conducted to include the 3- to 4-year population in 24 public schools. The aim of the study was to assess the experiences of parents and teachers involved in the project. This was a psychosocial qualitative study in which information was collected from a cohort of 23 parents and 17 teachers who attended three and two focus group sessions, respectively. A high degree of satisfaction with the school-located influenza vaccination program was consistently reported. The teachers reported creating a friendly environment and acting as companions to support children in the absence of their parents. They also considered the intranasal route, which avoids intramuscular puncture, as a facilitating element that turned the vaccination process into a kind of game. Parents emphasized the importance of vaccination to protect their children, and secondarily, to ensure protection of the family nucleus. Some parents who had their children already vaccinated in the health care center reported preference for the school setting, probably selecting this option in the future. The availability of school-based influenza vaccination promoted greater equity in accessing the vaccine and facilitated family reconciliation. To optimize coverage and minimize potential reluctance, providing the necessary information to parents both before and after vaccination was considered. School-located influenza vaccination was feasible and is a valuable strategy to be implemented in future campaigns.

Estimating averted illnesses from influenza vaccination for children and pregnant women – El Salvador, Panama, and Peru, 2011–2018

BackgroundEstimating the burden of disease averted by vaccination can assist policymakers to implement, adjust, and communicate the value of vaccination programs. Demonstrating the use of a newly available modeling tool, we estimated the burden of influenza illnesses averted by seasonal influenza vaccination in El Salvador, Panama, and Peru during 2011–2018 among two influenza vaccine target populations: children aged 6–23 months and pregnant women. MethodsWe derived model inputs, including incidence, vaccine coverage, vaccine effectiveness, and multipliers from publicly available country-level influenza surveillance data and cohort studies. We also estimated changes in illnesses averted when countries’ vaccine coverage was achieved using four different vaccine deployment strategies. ResultsAmong children aged 6–23 months, influenza vaccination averted an estimated cumulative 2,161 hospitalizations, 81,907 medically-attended illnesses, and 126,987 overall illnesses during the study period, with a prevented fraction ranging from 0.3 % to 12.5 %. Among pregnant women, influenza vaccination averted an estimated cumulative 173 hospitalizations, 6,122 medically attended illnesses, and 16,412 overall illnesses, with a prevented fraction ranging from 0.2 % to 10.9 %. Compared to an influenza vaccine campaign with equal vaccine distribution during March—June, scenarios in which total cumulative coverage was achieved in March and April consistently resulted in the greatest increase in averted illness (23 %-3,129 % increase among young children and 22 %-3,260 % increase among pregnant women). DiscussionInfluenza vaccination campaigns in El Salvador, Panama, and Peru conducted between 2011 and 2018 prevented hundreds to thousands of influenza-associated hospitalizations and illnesses in young children and pregnant women. Existing vaccination programs could prevent additional illnesses, using the same number of vaccines, by achieving the highest possible coverage within the first two months of an influenza vaccine campaign.

The Role of Pharmacists in Counteracting Vaccine Hesitancy: Effectiveness of the 2019 Carnia Project in Improving Adherence to Influenza Vaccination among Target Population.

Vaccine hesitancy has been included among the top ten threats to global health by the World Health Organization. Pharmacists can play a pivotal role in removing the individual barrier to vaccination, because of the relationship of trust they have with citizens and their ease of access. The aim of this study was to examine the impact of a pharmacy-based intervention to support the 2019 influenza vaccination campaign conducted in the Carnia district through one-to-one counseling. We analyzed data collected by pharmacists between 22 October 2019 and 20 January 2020, and trends in vaccination adherence in the context of the Local Health Authority and the entire province of Udine since 2016. The results showed that 77.2% of people who had not received an influenza vaccination in the previous year changed their minds about vaccination after receiving counseling. The pharmacy-based intervention improved influenza vaccination adherence in the target district (+13.4%), even when compared to the neighboring district of Gemona or considering the data in the broader local and provincial context, and this effect was particularly pronounced among those aged 65 to 74 years (p < 0.01). Considering these findings, pharmacies should be more effectively involved in the provision of public health services aimed at improving accessibility, timeliness, and equity.

Influenza Vaccine Uptake in Italy-The 2022-2023 Seasonal Influenza Vaccination Campaign in Italy: An Update from the OBVIOUS Project.

Influenza is a significant public health concern, with Italy being profoundly impacted annually. Despite extensive vaccination campaigns and cooperative initiatives between the Public Health Departments of Local Healthcare Authorities and family physicians, low vaccine uptake rates persist. This study builds upon the OBVIOUS project, providing an updated picture of influenza vaccine uptake in Italy through a representative sample. A cross-sectional computer-assisted web interviewing (CAWI) survey of 10,001 Italian citizens was conducted between 31 March and 5 June 2023. Our findings underscore the negative impact of a lack of awareness that a person is in a priority group for influenza vaccination (-26.1 percentage points in vaccine uptake) and the profound influence of social circles on vaccination decisions (-5 percentage points when unfavorable). Medical professionals played a pivotal role, with recommendations from family doctors significantly promoting vaccine uptake (+20.2 percentage points). Age, chronic conditions, and socio-demographic factors also influenced vaccination behaviors. For children, parental negative perceptions regarding the flu (-10.4 percentage points) and vaccine safety (-23.4 percentage points) were crucial determinants. The present study emphasizes the need for a comprehensive approach addressing awareness, societal beliefs, and tailored medical advice to enhance vaccination rates and protect public health in Italy.

Implementing a Successful Influenza and Updated COVID-19 Vaccination Campaign Among Healthcare Workers in a Delaware Healthcare Facility.

Although influenza (flu) and COVID-19 vaccines are highly recommended for healthcare workers, it is known that vaccination rates are suboptimal in healthcare settings. There is a need to optimize vaccination rates among healthcare workers as there are direct correlations to increased patient safety and protection of staff from healthcare associated infections. Our health care organization employed some novel strategies to increase the uptake of both flu and COVID-19 vaccinations by identifying and addressing common barriers. Barriers were identified through team meetings, review of previous years' vaccination trends, and historical information. Strategies to overcome these barriers included dissemination of information through various team meetings; identifying peer vaccination champions among specific groups that had historically low vaccination rates; creating a sense of urgency with weekly announcements regarding vaccinations; and computer screensavers with graphics promoting vaccinations. We believed education was key to success. Our focus was not only on the vaccination rates, but also on compliance which is defined as either getting the vaccine or submitting a declination after completing an education module. These efforts resulted in the organization achieving more than 95% compliance for both vaccinations. Our vaccination uptake rates for influenza were greater than 85% and updated COVID-19 vaccination rates were around 42%. We believe that the grass-root level work initiated for this year's campaign was one of the drivers for our success and some aspects could be replicated for vaccinating the public as well.

Strategic Planning of a Joint SARS-CoV-2 and Influenza Vaccination Campaign in the UK.

The simultaneous administration of SARS-CoV-2 and influenza vaccines is being carried out for the first time in the UK and around the globe in order to mitigate the health, economic, and societal impacts of these respiratory tract diseases. However, a systematic approach for planning the vaccine distribution and administration aspects of the vaccination campaigns would be beneficial. This work develops a novel multi-product mixed-integer linear programming (MILP) vaccine supply chain model that can be used to plan and optimise the simultaneous distribution and administration of SARS-CoV-2 and influenza vaccines. The outcomes from this study reveal that the total budget required to successfully accomplish the SARS-CoV-2 and influenza vaccination campaigns is equivalent to USD 7.29 billion, of which the procurement costs of SARS-CoV-2 and influenza vaccines correspond to USD 2.1 billion and USD 0.83 billion, respectively. The logistics cost is equivalent to USD 3.45 billion, and the costs of vaccinating individuals, quality control checks, and vaccine shipper and dry ice correspond to USD 1.66, 0.066, and 0.014, respectively. The analysis of the results shows that the choice of rolling out the SARS-CoV-2 vaccine during the vaccination campaign can have a significant impact not only on the total vaccination cost but also on vaccine wastage rate.

Acceptability, cost-effectiveness, and capacity of a facility-based seasonal influenza vaccination among high-risk groups: a study protocol in selected tertiary care hospitals of Bangladesh

BackgroundIn Bangladesh, seasonal influenza imposes considerable disease and economic burden, especially for those at high-risk of severe disease. The most successful approach for influenza prevention is the administration of a vaccine. Many poor and middle-income nations, including Bangladesh, do not have a national strategy or program in place for seasonal influenza vaccines, despite the World Health Organization’s (WHO) advice to prioritize high-risk populations. Additionally, there is a scarcity of substantial data on the cost-effectiveness of seasonal influenza vaccination in these countries. The aim of our study is to determine acceptability, health beliefs, barriers, and intention of receiving influenza vaccine among high-risk populations, assess the cost-effectiveness of implementing a facility-based seasonal influenza vaccination programme, and investigate the required capacity for a potential seasonal influenza vaccination programme.MethodsWe will undertake this study following STROBE guidelines. We will conduct the study in inpatient and outpatient departments of three selected tertiary-level hospitals leveraging the ongoing hospital-based influenza surveillance (HBIS) platform. The study population will include the WHO-defined four high-risk groups excluding healthcare workers: children six months to eight years, pregnant women, elderly ≥ 60 years, and adults with chronic diseases. We will collect quantitative data on participants’ acceptability, health beliefs, barriers, and vaccination intentions using the health belief model (HBM) from patients meeting the criteria for high-risk populations attending two public tertiary-level hospitals. In one of the two public tertiary-level hospitals, we will arrange an influenza vaccination campaign before the influenza season, where the vaccine will be offered free of cost to high-risk patients, and in the second hospital, vaccination will not be offered. Both the vaccinated and unvaccinated participants will then be followed-up once a month for one year to record any influenza-like illness, hospitalization, and death. Additional data for objective two will be collected from patients with symptoms of influenza-like illness (ILI) and severe acute respiratory infection (SARI) at one public and one private hospital to determine both direct and indirect costs associated with influenza illness. We will estimate the required number of influenza vaccines, safe injections, and total storage volume utilizing secondary data. We will use a deterministic Markov decision-analytic model to estimate the cost-effectiveness of facility-based influenza vaccination in Bangladesh.DiscussionThe results of this study will enable the National Immunization Technical Advisory Group and the Ministry of Health & Family Welfare of Bangladesh to decide what steps to take to develop and implement an influenza vaccination strategy targeting high-risk populations.Trial registrationThe Clinicaltrials.gov registration number is NCT05996549. The registration for the protocol version 2.0 took place in August 2023, with the initial participant being enrolled in March 2022.

Motivators for the public to receive the seasonal influenza vaccination and the effect of coronavirus disease 2019 pandemic on the uptake of the seasonal influenza vaccination.

The coverage of the seasonal influenza vaccine has always been sub-par. Understanding the motivators of receiving vaccines, especially during pandemics, could enhance and increase the coverage rates. The Saudi Ministry of Health launched its annual influenza vaccination campaign during the 2021 influenza season and provided vaccinations in primary healthcare settings. This study aims to explore public motivators to receive influenza vaccination, particularly during the coronavirus disease 2019 global pandemic. This cross-sectional study enrolled 783 participants who attended the influenza vaccination campaign. All persons who received the influenza vaccine in the influenza vaccination campaign held in Dammam, Saudi Arabia, from October to November 2021, were interviewed and completed a self-administered questionnaire. Odds ratio with a 95% confidence interval were estimated using the full model fit. The significance level was set as α = 0.05. The majority of the participants had more than high school education (81%), were males (66.2%), and married (59.6%), and 50.6% were below 35 years of age. Participants with higher education, health-care workers, and those who had been previously counseled on influenza vaccination were less likely to have started taking the influenza vaccination, whereas smokers and persons who do not have routine checkups were more likely to start influenza vaccination. The main motivator to take the influenza vaccine was the establishment of a vaccination campaign near the participant's workplace (62.2%), followed by advice from their physician (30.3%), and fear of having influenza disease (29.6%). Accessibility to the vaccination campaigns was the main motivator for receiving the vaccine followed by the advice from physician. Advice from physician and increasing mobile vaccination campaigns and mobile clinics would substantially increase influenza vaccine uptake.

Impact of Actively Offering Influenza Vaccination to Frail People during Hospitalisation: A Pilot Study in Italy.

Despite the worldwide recommendations for influenza immunisation, vaccination coverage for patients exposed to the highest risk of severe complications is still far from the optimal target. The need to take advantage of alternative methods to provide vaccination is essential. This study presents a hospital-based strategy which offers influenza vaccination to inpatients at discharge. This study was conducted during the 2022-2023 influenza season at the University Hospital of Palermo. A questionnaire was administered to identify the determinants for the acceptance of influenza vaccination in the frail population. Overall, 248 hospitalised patients were enrolled, of which 56.1% were female and 52.0% were over 65 years of age. The proportion of patients vaccinated against influenza during hospitalisation was 62.5%, an increase of 16% in influenza vaccination uptake among frail people in comparison with the previous influenza season (46.8% vaccinated during the 2021-22 influenza season). Factors significantly associated with vaccination acceptance were the following: to have received influenza vaccine advice from hospital healthcare workers (OR = 3.57, p = 0.001), to have been previously vaccinated for influenza (OR = 3.16 p = 0.005), and to have had a low level of education (OR = 3.56, p = 0.014). This study showed that offering influenza vaccination to hospitalised patients could be an effective strategy to increase vaccination coverage in the most vulnerable population, and these findings could be useful for planning and improving future influenza vaccination campaigns.

Seasonality as a driver of pH1N12009 influenza vaccination campaign impact

Although the most recent respiratory virus pandemic was triggered by a Coronavirus, sustained and elevated prevalence of highly pathogenic avian influenza viruses able to infect mammalian hosts highlight the continued threat of pandemics of influenza A virus (IAV) to global health. Retrospective analysis of pandemic outcomes, including comparative investigation of intervention efficacy in different regions, provide important contributions to the evidence base for future pandemic planning. The swine-origin IAV pandemic of 2009 exhibited regional variation in onset, infection dynamics and annual infection attack rates (IARs). For example, the UK experienced three severe peaks of infection over two influenza seasons, whilst Australia experienced a single severe wave. We adopt a seasonally forced 2-subtype model for the transmission of pH1N12009 and seasonal H3N2 to examine the role vaccination campaigns may play in explaining differences in pandemic trajectories in temperate regions. Our model differentiates between the nature of vaccine- and infection-acquired immunity. In particular, we assume that immunity triggered by infection elicits heterologous cross-protection against viral shedding in addition to long-lasting neutralising antibody, whereas vaccination induces imperfect reduction in susceptibility. We employ an Approximate Bayesian Computation (ABC) framework to calibrate the model using data for pH1N12009 seroprevalence, relative subtype dominance, and annual IARs for Australia and the UK. Heterologous cross-protection substantially suppressed the pandemic IAR over the posterior, with the strength of protection against onward transmission inversely correlated with the initial reproduction number. We show that IAV pandemic timing relative to the usual seasonal influenza cycle influenced the size of the initial waves of pH1N12009 in temperate regions and the impact of vaccination campaigns.

Implementation of an anti-flu vaccination campaign in a hospital pharmacy service

ObjectiveTo determine the impact of the implementation of an influenza vaccination campaign in a hospital pharmacy service on patients who are starting or receiving treatment with biological therapies. MethodA 15-month quasi-experimental study of patients starting or receiving treatment with biological therapies. Between October and December 2016 and October and December 2017, we compared influenza vaccination rates, the incidence of influenza in the study population, the direct impact of the vaccination campaign on the patient, the effect of the campaign on vaccination rates, and the results of the satisfaction survey. ResultsA total of 188 patients participated in the study. Of the patients who had not been vaccinated in the 2016/2017 campaign, 72.6% were vaccinated (p < 0.000) during the 2017/2018 campaign. No statistically significant differences were found between the 2016/2017 and 2017/2018 campaign (p = 0.636) in the percentage of patients who contracted flu after receiving the vaccine. In total, 99.5% thought that the campaign was a good initiative, and 50.5% reported that their decision to be vaccinated was influenced by the fact that the campaign was led by the hospital pharmacy service. ConclusionsThe implementation of the influenza vaccination campaign in the hospital pharmacy service achieved led to a marked increase in vaccination rates. This result underlines the key role played by the hospital pharmacy service in achieving this level of success.

Postmarketing observational study on the safety of 2021/2022 and 2022/2023 influenza vaccination campaigns in Italy: TheShinISS-Vax|Flu study protocol

IntroductionThe purpose of TheShinISS-Vax|Flu study is to examine the association between influenza vaccines and adverse events requiring hospital admission or emergency care during the influenza vaccination campaigns 2021/2022 and 2022/2023...

Preschool-located influenza vaccination and influenza-like illness surveillance: an Italian pilot experience

BackgroundWe describe the first school-located influenza vaccination campaign with quadrivalent live-attenuated influenza vaccine (LAIV) among pre-school children in Italy, coupled with an innovative school-centred influenza-like illnesses (ILIs) surveillance using a self-sampling non-invasive saliva collection method.MethodsThe pilot study was proposed during the 2021/2022 influenza season to fifteen pre-schools in the Milan municipality. LAIV was offered directly in school to all healthy children without contraindications. ILI differential diagnosis was conducted by real-time RT-PCR for influenza A/B and SARS-CoV-2.ResultsFive pre-schools were involved in the pilot project and overall, 135 families (31.2%) participated in the study, adhering to both surveillance and vaccination; 59% of families had an immigrant background. No pupil experienced adverse reactions after vaccination. Nineteen saliva samples were collected from sixteen children (11.8%). Six samples (31.6%) tested positive for SARS-CoV-2; none was positive for influenza A/B.ConclusionsThe participation in the immunisation campaign was good, considering possible absences due to COVID-19 pandemic, and the intranasal administration was well tolerated and helped to overcome parental hesitancy. Saliva sampling represented a useful tool to reduce children’s stress and increase parents’ compliance. The high participation of families with an immigrant background suggests that school-based interventions can represent an effective strategy to overcome socioeconomic and cultural barriers.

Pneumococcal vaccination coverage and adherence to recommended dosing schedules in adults: a repeated cross-sectional study of the INTEGO morbidity registry

BackgroundSince 2014, Belgium’s Superior Health Council has recommended pneumococcal vaccination for adults aged 19–85 years at increased risk for pneumococcal diseases with a specific vaccine administration sequence and timing. Currently, Belgium has no publicly funded adult pneumococcal vaccination program. This study investigated the seasonal pneumococcal vaccination trends, evolution of vaccination coverage and adherence to the 2014 recommendations.MethodsINTEGO is a general practice morbidity registry in Flanders (Belgium) that represents 102 general practice centres and comprised over 300.000 patients in 2021. A repeated cross-sectional study was performed for the period between 2017 and 2021. Using adjusted odds ratios computed via multiple logistic regression, the association between an individual’s characteristics (gender, age, comorbidities, influenza vaccination status and socioeconomic status) and schedule-adherent pneumococcal vaccination status was assessed.ResultsPneumococcal vaccination coincided with seasonal flu vaccination. The vaccination coverage in the population at risk decreased from 21% in 2017 to 18.2% in 2018 and then started to increase to 23.6% in 2021. Coverage in 2021 was highest for high-risk adults (33.8%) followed by 50- to 85-year-olds with comorbidities (25.5%) and healthy 65- to 85-year-olds (18.7%). In 2021, 56.3% of the high-risk adults, 74.6% of the 50+ with comorbidities persons, and 74% of the 65+ healthy persons had an adherent vaccination schedule. Persons with a lower socioeconomic status had an adjusted odds ratio of 0.92 (95% Confidence Interval (CI) 0.87–0.97) for primary vaccination, 0.67 (95% CI 0.60–0.75) for adherence to the recommended second vaccination if the 13-valent pneumococcal conjugate vaccine was administered first and 0.86 (95% CI 0.76–0.97) if the 23-valent pneumococcal polysaccharide vaccine was administered first.ConclusionPneumococcal vaccine coverage is slowly increasing in Flanders, displaying seasonal peaks in sync with influenza vaccination campaigns. However, with less than one-fourth of the target population vaccinated, less than 60% high-risk and approximately 74% of 50 + with comorbidities and 65+ healthy persons with an adherent schedule, there is still much room for improvement. Furthermore, adults with poor socioeconomic status had lower odds of primary vaccination and schedule adherence, demonstrating the need for a publicly funded program in Belgium to ensure equitable access.

Group 1 and group 2 hemagglutinin stalk antibody response according to age.

Antibodies elicited by seasonal influenza vaccines mainly target the head of hemagglutinin (HA). However, antibodies against the stalk domain are cross-reactive and have been proven to play a role in reducing influenza disease severity. We investigated the induction of HA stalk-specific antibodies after seasonal influenza vaccination, considering the age of the cohorts. A total of 166 individuals were recruited during the 2018 influenza vaccine campaign (IVC) and divided into groups: <50 (n = 14), 50-64 (n = 34), 65-79 (n = 61), and ≥80 (n = 57) years old. Stalk-specific antibodies were quantified by ELISA at day 0 and day 28 using recombinant viruses (cH6/1 and cH14/3) containing an HA head domain (H6 or H14) from wild bird origin with a stalk domain from human H1 or H3, respectively. The geometric mean titer (GMT) and the fold rise (GMFR) were calculated, and differences were assessed using ANOVA adjusted by the false discovery rate (FDR) and the Wilcoxon tests (p <0.05). All age groups elicited some level of increase in anti-stalk antibodies after receiving the influenza vaccine, except for the ≥80-year-old cohort. Additionally, <65-year-old vaccinees had higher group 1 antibody titers versus group 2 before and after vaccination. Similarly, vaccinees within the <50-year-old group showed a higher increase in anti-stalk antibody titers when compared to older individuals (≥80 years old), especially for group 1 anti-stalk antibodies. Seasonal influenza vaccines can the induction of cross-reactive anti-stalk antibodies against group 1 and group 2 HAs. However, low responses were observed in older groups, highlighting the impact of immunosenescence in adequate humoral immune responses.

Active medical recommendation is the best tool for increasing influenza vaccine coverage in healthy adult workers

IntroductionIn Spain, influenza vaccination is available in companies free of charge for their workers. Despite this, vaccination coverage against influenza is very low in these groups. ObjectivesThe aim of this work is to know the reasons for acceptance of influenza vaccination in a working population. MethodsDuring the 2021–2022 influenza vaccination campaign, we conducted a survey of two groups of workers at the automobile factories of RENAULT ESPAÑA S.A. in the cities of Valladolid and Palencia (Spain). The first group (NV) was formed by 304 (33.5%) workers who did not receive the influenza vaccine in the previous season. The second (V) was formed by 604 workers (66.5%) who had been vaccinated against influenza at least the previous season. In the NV group, they were asked the reasons why they did not get vaccinated the previous season and if they did so in 2021–2022. In group V, only the reasons for continuing to be vaccinated were asked. ResultsIn NV, the main reason for avoiding vaccination in the previous season was the lack of perception of the severity of the influenza infection (74.7%), and 31.6% and 29.0% of them decided to get vaccinated during the 2021–2022 season due to the fear of co-infection of SARS-CoV-2 and influenza and medical recommendations respectively. The 83.5% of group V responded that the reason for getting vaccinated in 2021–2022 was their adherence to vaccination. ConclusionsThe results show that medical recommendation is the best tool to vaccinate workers against influenza and make them adhere to it. Also, the fear to co-infection of COVID-19 and flu was a frequent reason for getting vaccinated, above all in NV.

Historical Perspectives on the Neurologic Manifestations of Viral Pandemics

Neurologic symptoms have been reported in over 30% of hospitalized patients with coronavirus disease 2019 (COVID-19), but the pathogenesis of these symptoms remains under investigation. Here, we place the neurologic complications of COVID-19 within the context of three historical viral pandemics that have been associated with neurologic diseases: (1) the 1918 influenza pandemic, subsequent spread of encephalitis lethargica, and lessons for the study of COVID-19-related neuroinflammation; (2) the controversial link between the 1976 influenza vaccination campaign and Guillain-Barré Syndrome and its implications for the post- and parainfectious complications of COVID-19 and COVID-19 vaccination; and (3) potential applications of scientific techniques developed in the wake of the human immunodeficiency virus pandemic to the study of postacute sequelae of COVID-19.

Acceptance or rejection of vaccination against influenza and SARS-CoV2 viruses among primary care professionals in Central Catalonia. A cross-sectional study

BackgroundWith the outbreak of the SARS-CoV-2 pandemic, the uncertainty about the real impact of coinfection with other viruses, and the increased risk of mortality in the case of coinfection with the influenza virus, health authorities recommended an increase in influenza vaccination coverage among at-risk groups to minimize the possible impact on individuals and the healthcare system. Recommendations for influenza vaccination during the 2020–2021 campaign in Catalonia were focused on increasing vaccination coverage, especially for social and healthcare workers, elderly people and at-risk individuals of any age. The objectives for the 2020–2021 season in Catalonia were to reach 75 % for the elderly and for social and healthcare workers, and 60 % for pregnant women and at-risk groups. In the case of healthcare professionals and those over 65 years of age, the target was not met. Vaccination coverage reached 65.58 % and 66.44 %, respectively (in the 2019–2020 campaign it was 39.08 %).Analysing and following up on the background and context in which health professionals accept influenza vaccination will help develop strategies for long-term influenza vaccination campaigns. The present study looks at healthcare professionals in a specific territory where the reasons for acceptance or refusal of the influenza vaccine during the 2021–2022 vaccination campaign, as well as the reasons for acceptance or refusal of the COVID-19 vaccine, were analysed by means of an online survey. MethodsCalculations suggested that a random sample of 290 individuals would be sufficient to estimate, with 95% confidence and a precision of +/- 5 percentage units, a population percentage that was expected to be around 30%. The required replacement rate was 10%.The R statistical software (version 3.6.3) was used for the statistical analysis. Confidence intervals were 95 % and contrasts with a p-value of < 0.05 were considered significant. FindingsOf the 1921 professionals to whom the survey was sent, 586 (30.5%) responded to all the questions. 95.2% of respondents were vaccinated against COVID-19 and 66.2% against influenza.It was observed that the relationship between sociodemographic characteristics and the decision to get vaccinated was different for influenza and COVID-19. The reasons for accepting the COVID-19 vaccine with the highest percentage were firstly protecting family (82.2%), self-protection (74.9%) and also protecting patients (57.8%). Otherwise, other reasons not described in the survey (50%) and mistrust (42.3%) were the reasons for rejecting the COVID-19 vaccine.Regarding influenza, the most relevant reasons for which professionals got vaccinated were self-protection (70.7%), protecting family (69.7%) and protecting patients (58.4%). Reasons for refusing the influenza vaccine were reasons not mentioned in the survey (29.1%) and the low probability of suffering complications (27.4%). InterpretationAnalysing the context, territory, sector, and the reasons for both accepting and refusing a vaccine will help develop effective strategies. Although vaccination coverage against COVID-19 was very high throughout Spain, a marked increase in influenza vaccination in the context of COVID-19 was observed among healthcare professionals in the Central Catalonia region compared to the previous pre-pandemic campaign.

Increasing influenza vaccination coverage in healthcare workers: analysis of an intensified on-site vaccination campaign during the COVID-19 pandemic

PurposeInfluenza infections have substantial impact on healthcare institutions. While vaccination is the most effective preventive measure against influenza infection, vaccination coverage in healthcare workers is low. The study investigates the impact of an intensified influenza vaccination campaign in a maximum-care hospital on influenza vaccination coverage in healthcare workers during the COVID-19 pandemic in 2020/21.MethodsBuilding on findings from our previously published review Schumacher et al. (Infection 49(3): 387, 2021), an intensified influenza vaccination campaign comprising a mobile vaccination team providing on-site vaccination and vaccination at a recurring central vaccination site in addition to promotional measures was performed and analysed regarding vaccination coverage. A survey querying vaccination motivation was performed. Campaign strategies and vaccination coverage of influenza seasons between 2017/18 and 2019/20 were analysed.ResultsThe influenza vaccination campaign 2020/21 led to a significant 2.4-fold increase yielding an overall vaccination coverage of 40% among healthcare workers. A significant increase in vaccination coverage was observed across all professional fields; especially among nurses, a 2.7-fold increase, reaching a vaccination coverage of 48%, was observed. The COVID-19 pandemic positively influenced vaccination decision in 72% of first time ever or first time in over ten years influenza vaccinees. Vaccination coverage during prior vaccination campaigns focusing on educational measures did not exceed 17%.ConclusionA mobile vaccination team providing on-site vaccination and vaccinations at a central vaccination site in addition to promotional measures can be implemented to increase influenza vaccination coverage in healthcare workers. Our concept can inform influenza and other vaccination campaigns for healthcare workers.