Seasonal influenza immunisation in Europe. Overview of recommendations and vaccination coverage for three seasons: pre-pandemic (2008/09), pandemic (2009/10) and post-pandemic (2010/11)

Caregivers' understanding of childhood influenza vaccination during the epidemic in China. A mixed-methods study

Introduction

Influenza vaccination uptake among young children has been poor in China, but it is unclear how it changed during the COVID-19. This study aimed to investigate the uptake status and reasons of childhood influenza vaccination during the pandemic in China.

Methods

A mixed-methods study combining a questionnaire survey and semi-structured interviews was conducted in Anhui, Shaanxi, and Guangdong provinces between September and November 2021. 2081 caregivers completed the valid questionnaire. 38 caregivers participated in interviews, and data were analyzed thematically, using deductive and inductive coding.

Results

A total of 2081 caregivers completed the valid questionnaire, and 38 caregivers participated in interviews. Among the caregivers, a total of 1796 were in the age group for high-risk groups in the 2019-2020 flu season, and 46.10% reported that their children received influenza vaccination in the 2019-2020 flu season; 43.63% said that they vaccinated their children against influenza in the 2020-2021 flu season. Many caregivers indicated that the adoption of nonpharmacologic interventions (NPIs) during COVID-19 reduced the risk of influenza infection for children. Most caregivers consider the severity of influenza to be low, and some confused the common cold with influenza. Meanwhile, some caregivers lack confidence in the vaccine's effectiveness and importance. They thought that vaccines are not effective in preventing the constantly mutating virus. Despite clear perceptions about the severity of influenza and the effectiveness of the vaccine, we found that most caregivers did not receive any relevant medical information, and the communication about vaccines between caregivers and professional information sources, such as healthcare workers, is inadequate. Hence, caregivers have no scientific evidence to back up their perceptions. In terms of access to vaccination service, caregivers reported conflicts between time of vaccination service and their schedule, and the need for vaccine prices to be reduced.

Discussion

Targeted interventions are needed to address caregivers' lack of risk perception on influenza during COVID-19 and promote communication between caregivers and professional information sources. Extending vaccination service hours and increasing the number of vaccine clinics close to residential areas and expansion of financing sources for self-paid vaccination could facilitate the access to influenza vaccination service.

Factors Influencing the Uptake of Seasonal Influenza Vaccination among Community-Dwelling Older Adults during COVID-19: A Mixed Methods Study

Background: Despite making the influenza vaccine accessible and affordable, vaccination rates remained low among community-dwelling older adults. Therefore, this study aimed to explore the factors influencing vaccine uptake and the impact of COVID-19 on vaccine uptake among community-dwelling older adults in Singapore. Methods: A mixed methods study involving a survey and semi-structured interviews were conducted between September 2020 and July 2021. Community-dwelling older adults aged ≥ 65 years were recruited from 27 Community Nurse Posts. Data on participants’ demographics, health condition(s), vaccination status, attitudes towards influenza infections and vaccinations, willingness to pay, intention for future vaccination and source of information were collected via the survey. Semi-structured interviews were conducted to understand vaccination experiences, key enablers and barriers, and the impact of COVID-19 on vaccine uptake. All interviews were analysed using Braun and Clarke’s thematic analysis. Quantitative data were analysed using descriptive statistics, chi-square tests and multinomial logistic regressions. Results: A total of 235 participants completed the survey. Living arrangement was a statistically significant contributing factor for influenza vaccine uptake (ꭓ2= −0.139; p = 0.03). Participants who lived alone were 2.5 times more likely to be vaccinated than those living with others (OR = 2.504, 95% CI: 1.294–4.842, p = 0.006). Avoidance of getting infected (82.5%), avoidance of transmission to others (84.7%), and advice from healthcare professionals to receive vaccination (83.4%) were key enablers, while concerns about possible side effects (41.2%), the effectiveness of the vaccine (42.6%), and not having enough information (48.1%) were barriers. Twenty participants were interviewed. The findings were congruent with the survey results. Five themes were identified as follows: (1) Perceived importance of influenza vaccination, (2) Sphere of influence, (3) Healthcare schemes and medical subsidies, (4) Psychological impediments, and (5) Inconsistent emphases at various touch points. Conclusions: Greater public health efforts are needed to reach out to the larger population of older adults of different living arrangements and those concerned about the possible side effects and effectiveness of the influenza vaccine. Healthcare professionals need to provide more information to address these concerns, especially during COVID-19, to encourage vaccine uptake.

Uptake of Influenza Vaccine and Factors Associated with Influenza Vaccination among Healthcare Workers in Tertiary Care Hospitals in Bangladesh: A Multicenter Cross-Sectional Study

Influenza, highly contagious in hospital settings, imposes a substantial disease burden globally, and influenza vaccination is critical for healthcare workers (HCWs) to prevent this illness. This study assessed influenza vaccine uptake, including its associated factors among HCWs of tertiary care hospitals in Bangladesh. Between September and December 2020, this multicenter study included 2046 HCWs from 11 hospitals. Face-to-face interviews were conducted using a semi-structured questionnaire to collect data from physicians, nurses, and cleaning and administrative staff for the survey. Only 13.8% (283/2046) of HCWs received the influenza vaccine, of which the majority (76.7%, 217/283) received it for free from the hospital. Nurses had the highest (20.0%, 187/934) influenza vaccine coverage, followed by physicians at 13.5% (71/526), whereas cleaning staff had the lowest at 6.0% (19/318). Among unvaccinated HCWs, the desire to get vaccinated was high (86.2%), with half of the respondents even being willing to pay for it. The HCWs who were aware of the influenza vaccine were over five times more likely to get the vaccine (OR 5.63; 95% CI: 1.04, 1.88) compared to those who were not. HCWs in Bangladesh were vaccinated against influenza at a very low rate. Free and mandatory influenza vaccination programs should be initiated to optimize vaccine coverage among HCWs.

Advances in Pharmacy Practice: A Look towards the Future

This review looks at the factors that may influence practice in the future. Transformation could occur at 3 levels. Firstly, the traditional profession of the pharmacist as a dispenser of medicines is expanding. Secondly, the pharmacist’s activities are progressing into new healthcare fields. Thirdly, other changes are stimulated by global developments. This review may be helpful for pharmacy and healthcare leaders looking at the future configuration and aims of their pharmacy services.

Influenza vaccination of school teachers: A scoping review and an impact estimation

Introduction

Influenza vaccination, besides protecting traditional risk groups, can protect employees and reduce illness-related absence, which is especially relevant in sectors with staff shortages. This study describes current knowledge of influenza vaccination in teachers and estimates its potential impact.

Methods

We conducted a scoping review of the considerations for and impact of influenza vaccination of schoolteachers (grey and scientific literature up to 2020 March, complemented with interviews). We then estimated the potential impact of teacher vaccination in the Netherlands, with different scenarios of vaccine uptake for 3 influenza seasons (2016–2019). Using published data on multiple input parameters, we calculated potentially averted absenteeism notifications, averted absenteeism duration and averted doctor visits for influenza.

Results

Only one scientific paper reported on impact; it showed lower absenteeism in vaccinated teachers, whereas more knowledge of vaccination impact was deemed crucial by 50% of interviewed experts. The impact for the Netherlands of a hypothetical 50% vaccine uptake was subsequently estimated: 74–293 potentially averted physician visits and 11,178–28,896 potentially averted days of influenza absenteeism (on ≈200,000 total teacher population). An estimated 12–32 vaccinations were required to prevent one teacher sick-leave notification, or 3.5–9.1 vaccinations to prevent one day of teacher absenteeism (2016–2019).

Conclusion

Scientific publications on influenza vaccination in teachers are few, while public interest has increased to reduce teacher shortages. However, school boards and public health experts indicate requiring knowledge of impact when considering this vaccination. Estimations of 3.5–9.1 vaccinated teachers preventing one day of influenza-related sick leave suggest a possible substantial vaccination impact on absenteeism. Financial incentives, more accessible on-site vaccinations at workplaces, or both, are expected to increase uptake, but more research is needed on teachers’ views and vaccine uptake potential and its cost-effectiveness. Piloting free on-site influenza vaccination in several schools could provide further information on teacher participation.

Seasonal Influenza Vaccination at a German University Hospital: Distinguishing Barriers Between Occupational Groups

The annual influenza vaccination has been officially recommended for medical staff in Germany since 1988. Nevertheless, the vaccination rate among medical staff is still low. The present study deals with the influenza vaccination rate of staff at a German University hospital over time as well as with the reasons that led to a positive vaccination decision and the barriers to acceptance of vaccination. For this purpose, the staff members received questionnaires in which they were asked about influenza vaccination and the reasons for or against vaccination. In addition, the questionnaire contains information on gender, age group, occupational group and presence of a chronic co-morbidity. Logistic regression analysis was used to investigate which of these predictors most strongly influenced the vaccination decision. It was shown that the reasons for or against vaccination differ significantly between the occupational groups and that the occupational group affiliation has the greatest influence on the vaccination decision in the comparison of the investigated predictors. In order to achieve a positive influence on vaccination acceptance, future measures should focus on increasing confidence in vaccination and on increasing the perception of risk from influenza illness. The findings may contribute to future targeted strategies to increase vaccination rates and suggest occupational group-specific interventions.

Implementation of EACS vaccination recommendations among people living with HIV

Objectives

With modern combination antiretroviral Treatment (cART) a normal life expectancy among people living with HIV (PLWH) has become reality if started early enough prior to the onset of more pronounced immunodeficiency. Therefore, prevention measures against other infectious diseases among this vulnerable group have gained increased attention. Indeed, the EACS guidelines recommend vaccinations against HAV, HBV, HPV, Influenza, Neisseria meningitidis, Streptococcus pneumoniae and VZV in HIV-infected adults.

Methods

All PLWH under cART attending our ID outpatient clinic between April to June 2018, were assessed during consultation for vaccination status regarding pneumococcus, Hepatitis A and B, influenza, varicella, meningococcus and HPV using a pre-defined questionnaire, vaccination certificates and medical records. In addition, the cohort database was screened for Hepatitis A and B serology and HIV surrogate markers.

Results

A total of 305 PLWH (82.3% male, 17.7% female) was included, median age was 48 years (IQR 47–51). Median CD4 + T cell count was 543 (IQR 304–770), and for 297 (97.4%) PLWH CD4 + T cell count was ≥ 200/ul. The viral load was undetectable (< 40 copies/ml) in 289 (94.8%) cases. Highest vaccination rates were observed for HAV (87.4%), Streptococcus pneumoniae (77.4%) and Influenza (76.5%). 64.3% PLWH got vaccinated against HBV, whereas VZV vaccination only played a minor role, in the context of the high rate of cleared infections (99.0%). Lowest vaccination rates were detected for HPV (0%) and Neisseria meningitidis (3.0%).

Conclusions

Our data suggest that vaccination rates among PLWH are higher compared to the general German population. Implementation of EACS guidelines into daily routine though is not fully executed and the need for improving vaccination rates has to be emphasized. Centrally organized vaccination registers as well as electronic medical records could be helpful tools to detect a lack of vaccination coverage and send digital vaccination reminders particularly among risk groups.

Influenza and Pertussis Maternal Vaccination Coverage and Influencing Factors in Spain: A Study Based on Primary Care Records Registry

The purpose was to determine the coverage of maternal vaccination against influenza and pertussis, and the characteristics associated with being vaccinated, in a health area of Catalonia, Spain. Some 36,032 anonymized and computerized clinical records registries of pregnant women from Primary Care Centres (e-CAP database) were analysed, from between 2015 and 2018. Vaccination coverage and the association with sociodemographic variables and clinical conditions were estimated using a Poisson regression model. Maternal vaccination coverage against influenza ranged between 11.9% in 2015 and 6.8% in 2018, following a decreasing trend (p < 0.001). Coverage with the tetanus toxoid, diphtheria toxoid, and acellular pertussis vaccine varied between 49.8% in 2016 and 79.4% in 2018, following an increasing trend (p < 0.001). Having living children and suffering from obesity were factors associated with not being vaccinated against both infections. The predictive variables of vaccination against influenza were diabetes (IRR: 2.17, 95% CI: 1.42−3.30) and asthma (IRR: 2.05, 95% CI: 1.76−2.38); and for pertussis, it was asthma (IRR: 1.10, 95% CI: 1.03−1.17). Different socio-demographic factors and chronic conditions in pregnant women were associated with maternal vaccination, and which will have to be taken into account in clinical practice when implementing strategies to improve the coverage of the programme.

Time Trends (2012-2020), Sex Differences and Predictors for Influenza Vaccination Uptake among Individuals with Chronic Obstructive Pulmonary Disease in Spain

(1) Background: To analyze time trends, sex differences, and factors associated with influenza vaccination uptake among individuals with COPD in Spain, 2012−2020. (2) Methods: A cross-sectional study based on data from the European Health Surveys for Spain, 2020 (EHSS2020) and 2014 and from the Spanish National Health Interview Surveys for 2017 and 2012. (3) Results: The study included 65,447 participants. Prevalence of COPD was 5.9% (n = 3855). Overall, the influenza vaccination uptake among COPD patients was 57.8% versus 28.6% for those without COPD (p < 0.001). Men with COPD reported higher uptake than women in all the surveys studied. Neither the crude nor the multivariable analysis showed a significant variation change overtime for people with COPD. However, among those aged <65 years, crude uptake decreased from 2012 to 2020 (39.4% vs. 33.3%; p = 0.039). Over the entire period, men were vaccinated significantly more than women (OR 1.28; 95% CI 1.12−1.47). Among COPD participants, included in the EHSS2020, independent predictors of vaccine uptake included being male, higher age, reporting no current smoking and suffering cancer or heart disease. (4) Conclusions: In COPD patients, the influenza vaccination uptake is below desirable levels and did not improve from 2012 to 2020. Sex differences are found, with consistent and constant lower uptake among women with COPD. The observed lower uptake among COPD women and patients with unhealthy lifestyle requires increased attention.

Resilience and intention of healthcare workers in China to receive a COVID-19 vaccination: The mediating role of life satisfaction and stigma

Aims

The present study investigated the association between resilience, stigma, life satisfaction and the intention to receive a COVID‐19 vaccination among Chinese HCWs. It also explored the mediating role of stigma and life satisfaction on the association between resilience and intention to receive a COVID‐19 vaccination.

Design

An anonymous cross‐sectional survey.

Methods

1733 HCWs from five hospitals in four provinces of mainland China completed a cross‐sectional online survey in October and November 2020.

Results

Among the HCWs, the rate of intention to receive a COVID‐19 vaccination was 73.1%. Results from structural equation modelling showed that resilience was associated both directly, and indirectly with greater intent to receive a COVID‐19 vaccination through two pathways: first by increasing life satisfaction, and second by reducing stigma and increasing life satisfaction.

Conclusion

Promoting the resilience of HCWs has the potential to increase the COVID‐19 vaccination uptake rate among HCWs in China.

Impact

This study tested the relationship between several psychological factors and the COVID‐19 vaccination intention of HCWs in China, finding that resilience played a significant role in improving COVID‐19 vaccination intention rates by reducing stigma and increasing life satisfaction.

Infectious diseases among elderly persons: Results from a population-based observational study in Shandong province, China, 2013-2017

Background

The health of the elderly is one of the major challenges in today's ageing society. However, research on infectious diseases among the elderly is limited. This study aimed to describe the epidemiological characteristics and dynamics of infectious diseases among the elderly population aged ≥60 years in Shandong province, China.

Methods

Incidence data for infectious diseases were collected from the Shandong Multi-Center Healthcare Big Data Platform from January 2013 to June 2017, which involved 550 432 elderly persons. We compared the incidence of each infectious disease and disease category, stratified by age, gender, and region. Annual percentage change (APC) was estimated using logarithmic linear regression to examine the incidence trends. Poisson regression was conducted to identify the effect of demographic factors on incidence, with incidence rate ratio (IRR) and their 95% confidence intervals (CIs) estimated.

Results

A total of 27 595 cases of 102 infectious diseases were reported during the study period, with an overall incidence of 1425.51/100 000 person-years. The most common infectious diseases were respiratory and mucocutaneous diseases among the elderly persons, with annual increases of 17.45% and 20.44%, respectively (both P<0.05). In rural areas, the incidence of respiratory, gastrointestinal, blood- and sex-transmitted, and mucocutaneous infections increased significantly, with APCs of 178.52%, 204.66%, 28.24%, 63.01%, respectively (all P<0.05). Elderly males had a higher risk of infections than that of females, with the highest IRRa of 2.94 (95% confidence interval (CI) = 2.89, 3.00) in respiratory diseases. The elderly aged 85-89 years had a much higher risk of respiratory diseases than those aged 60-64 years (IRRa = 9.85, 95%CI: 9.39, 10.33); however, the risk of blood- and sex-transmitted diseases was highest among the elderly aged 65-69 years (IRRa = 1.24, 95% CI = 1.06, 1.45).

Conclusions

Ageing population are facing a substantial challenge on infectious diseases. More attention should be paid to infections with significant growth. Targeted strategies and measures on elderly persons in different regions and subgroups are urgently needed.

A multi-country investigation of influenza vaccine coverage in pregnant individuals, 2010-2016

BACKGROUND

Many countries recommend influenza vaccination during pregnancy. Despite this recommendation, influenza vaccine among pregnant individuals remains under-utilized and uptake varies by country. Factors associated with influenza vaccine uptake during pregnancy may also vary across countries.

METHODS

As members of the Pregnancy Influenza Vaccine Effectiveness Network (PREVENT), five sites from four countries (Australia, Canada, Israel, and the United States) retrospectively identified cohorts of individuals aged 18-50 years who were pregnant during pre-defined influenza seasons. Influenza vaccine coverage estimates were calculated for the 2010-11 through 2015-16 northern hemisphere and the 2012 through 2015 southern hemisphere influenza seasons, by site. Sites used electronic health records, administrative data, and immunization registries to collect information on pregnancy, health history, demographics, and vaccination status. Each season, vaccination coverage was calculated as the percentage of individuals who received influenza vaccine among the individuals in the cohort that season. Characteristics were compared between those vaccinated and unvaccinated, by site.

RESULTS

More than two million pregnancies were identified over the study period. Influenza vaccination coverage ranged from 5% to 58% across sites and seasons. Coverage increased consistently over the study period at three of the five sites (Western Australia, Alberta, and Israel), and was highest in all seasons at the United States study site (39-58%). Associations with vaccination varied by country and across seasons; where available, parity >0, presence of a high-risk medical condition, and urban residence were consistently associated with increased likelihood of vaccination.

CONCLUSIONS

Though increasing, uptake of influenza vaccine among pregnant individuals remains lower than recommended. Coverage varied substantially by country, suggesting an ongoing need for targeted strategies to improve influenza vaccine uptake in this population.

Immunogenicity and safety of a quadrivalent high-dose inactivated influenza vaccine compared with a standard-dose quadrivalent influenza vaccine in healthy people aged 60 years or older: a randomized Phase III trial

A quadrivalent high-dose inactivated influenza vaccine (IIV4-HD) is licensed for adults ≥65 y of age based on immunogenicity and efficacy studies. However, IIV4-HD has not been evaluated in adults aged 60–64 y. This study compared immunogenicity and safety of IIV4-HD with a standard-dose quadrivalent influenza vaccine (IIV4-SD) in adults aged ≥60 y. This Phase III, randomized, modified double-blind, active-controlled study enrolled 1,528 participants aged ≥60 y, randomized 1:1 to a single injection of IIV4-HD or IIV4-SD. Hemagglutination inhibition (HAI) geometric mean titers (GMTs) were measured at baseline and D 28 and seroconversion assessed. Safety was described for 180 d after vaccination. The primary immunogenicity objective was superiority of IIV4-HD versus IIV4-SD, for all four influenza strains 28 d post vaccination in participants aged 60–64 and ≥65 y. IIV4-HD induced a superior immune response versus IIV4-SD in terms of GMTs in participants aged 60–64 y and those aged ≥65 y for all four influenza strains. IIV4-HD induced higher GMTs in those aged 60–64 y than those aged ≥65 y. Seroconversion rates were higher for IIV4-HD versus IIV4-SD in each age-group for all influenza strains. Both vaccines were well tolerated in participants ≥60 y of age, with no safety concerns identified. More solicited reactions were reported with IIV4-HD than with IIV4-SD. IIV4-HD provided superior immunogenicity versus IIV4-SD and was well tolerated in adults aged ≥60 y. IIV4-HD is assumed to offer improved protection against influenza compared with IIV4-SD in adults aged ≥60 y, as was previously assessed for adults aged ≥65 y.

Cross-sectional telephone surveys as a tool to study epidemiological factors and monitor seasonal influenza activity in Malta

Background

Seasonal influenza has major implications for healthcare services as outbreaks often lead to high activity levels in health systems. Being able to predict when such outbreaks occur is vital. Mathematical models have extensively been used to predict epidemics of infectious diseases such as seasonal influenza and to assess effectiveness of control strategies. Availability of comprehensive and reliable datasets used to parametrize these models is limited. In this paper we combine a unique epidemiological dataset collected in Malta through General Practitioners (GPs) with a novel method using cross-sectional surveys to study seasonal influenza dynamics in Malta in 2014–2016, to include social dynamics and self-perception related to seasonal influenza.

Methods

Two cross-sectional public surveys (n = 406 per survey) were performed by telephone across the Maltese population in 2014–15 and 2015–16 influenza seasons. Survey results were compared with incidence data (diagnosed seasonal influenza cases) collected by GPs in the same period and with Google Trends data for Malta. Information was collected on whether participants recalled their health status in past months, occurrences of influenza symptoms, hospitalisation rates due to seasonal influenza, seeking GP advice, and other medical information.

Results

We demonstrate that cross-sectional surveys are a reliable alternative data source to medical records. The two surveys gave comparable results, indicating that the level of recollection among the public is high. Based on two seasons of data, the reporting rate in Malta varies between 14 and 22%. The comparison with Google Trends suggests that the online searches peak at about the same time as the maximum extent of the epidemic, but the public interest declines and returns to background level. We also found that the public intensively searched the Internet for influenza-related terms even when number of cases was low.

Conclusions

Our research shows that a telephone survey is a viable way to gain deeper insight into a population’s self-perception of influenza and its symptoms and to provide another benchmark for medical statistics provided by GPs and Google Trends. The information collected can be used to improve epidemiological modelling of seasonal influenza and other infectious diseases, thus effectively contributing to public health.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12889-021-11862-x.

Trends, Uptake, and Predictors of Influenza Vaccination Among Healthcare Practitioners During the COVID-19 Pandemic Flu Season (2020) and the Following Season (2021) in Saudi Arabia

Background

Healthcare practitioners (HCPs) are at high risk of influenza. Seasonal influenza vaccines can reduce influenza-associated morbidity in healthcare settings, but despite mandatory influenza vaccination in the Kingdom of Saudi Arabia, the vaccination uptake rate among HCPs is below expectations. This study investigated vaccination trends from 2017 to 2020 to identify factors affecting vaccination among HCPs during the COVID-19 pandemic flu and subsequent seasons.

Methods

Cross-sectional study among HCPs was conducted in January 2021. A structured questionnaire was shared via social media. Vaccine uptake predictors were identified using descriptive statistics and logistic regression models (p-value 0.05).

Results

A total of 424 HCPs (118 physicians and 306 nurses) completed the questionnaire. Vaccine uptake increased from 2017 to 2019 (45% to 52% to 62%) but fell (to 59%) during the 2020 COVID-19 pandemic flu season. Multivariable analysis indicated participants >40 years old (AOR 3.09, 95% CI 1.64–5.83), female (AOR 1.74, 95% CI 1.13–2.67), non-Saudi (AOR 2.62, 95% CI 1.72–4.01), nurses (AOR 2.70, 95% CI 1.75–4.17), and who possessed accurate knowledge of the flu vaccine efficacy duration (AOR 3.04, 95% CI 1.87–4.94) were more likely to have received the vaccine. However, 79% of HCPs declared their intention to be vaccinated in the 2021 flu season, with participants >40 years old, female (AOR 2.25, 95% CI 1.38–3.68), non-Saudi (AOR 3.79, 95% CI 2.34–6.16), or nurses (AOR 2.94, 95% CI 1.82–4.76) more likely to do so.

Conclusion

Influenza vaccination uptake declined among HCPs during the 2020 flu season compared with the previous season but is expected to increase in the upcoming 2021 season. Nevertheless, the findings are encouraging and indicate increased willingness of HCPs to become vaccinated in the upcoming 2021 season, but coverage could be further increased by policymakers via a comprehensive plan focusing particularly on younger HCPs, Saudis, males, and physicians.

Influence of commissioned provider type and deprivation score on uptake of the childhood flu immunization

BACKGROUND

Since 2015/16 the UK seasonal influenza immunization programme has included children aged 5 and 6 years. In the South West of England school-based providers, GPs or community pharmacies were commissioned to deliver the vaccine depending on the locality. We aimed to assess variation in vaccine uptake in relation to the type of commissioned provider, and levels of socioeconomic deprivation.

METHODS

Data from the South West of England (2015-16 season) were analysed using multilevel logistic regression to assess variation in vaccine uptake by type of commissioned provider, allowing for clustering of children within delivery sites.

RESULTS

Overall uptake in 5 and 6 year olds was 34.3% (37 555/109 404). Vaccine uptake was highest when commissioned through school-based programmes 50.2% (9983/19 867) and lowest when commissioned through pharmacies, 23.1% (4269/18 479). Delivery through schools resulted in less variation by site and equal uptake across age groups, in contrast to GP and pharmacy delivery for which uptake was lower among 6 year olds. Vaccine uptake decreased with increasing levels of deprivation across all types of commissioned provider.

CONCLUSION

School-based programmes achieve the highest and most consistent rates of childhood influenza vaccination. Interventions are still needed to promote more equitable uptake of the childhood influenza vaccine.

Countries with high deaths due to flu and tuberculosis demonstrate lower COVID-19 mortality: roles of vaccinations

Deaths due to the ongoing COVID-19 pandemic vary (3-1681 deaths/million and mortality rates 0.71-14.54%) and are far greater in some countries compared to others. This observation led us to perform epidemiological analysis, using data in the public domain, to study the correlation of COVID-19 with the prevalence and vaccination strategies for two respiratory pathogens: flu and tuberculosis (TB). Countries showing more than 1000 COVID-19 deaths were selected at three time points during the ongoing pandemic: 17 May, 1 October and 31 December 2020. The major findings of this study that are broadly consistent at all three time points are: First, countries with high flu deaths negatively correlate with COVID-19 deaths/million. Second, TB incidences and deaths negatively correlate with COVID-19 deaths/million. Countries displaying high TB and flu deaths (Nigeria, Ethiopia, Myanmar, Indonesia, India) display lower COVID-19 deaths/million compared to countries with low TB and flu deaths (Italy, Spain, USA, France). Third, countries with greater flu vaccination display lower flu incidences but higher COVID-19 deaths/million and mortality rates. On the other hand, Bacillus Calmette Guerin (BCG) vaccination negatively correlates with Covid-19 deaths/million. Fourth, countries with only BCG, but no flu, vaccination show delayed and lower number of COVID-19 deaths/million compared to countries with flu, but no BCG, vaccination. Fifth, countries with high BCG vaccination coverage as well as high TB deaths display the lowest COVID-19 deaths/million. The implications of this global study are discussed with respect to the roles of respiratory infections and vaccinations in lowering COVID-19 deaths.

A Call for a Reform of the Influenza Immunization Program in Mexico: Epidemiologic and Economic Evidence for Decision Making

Limited information is available to determine the effectiveness of Mexico's national influenza vaccination guidelines and inform policy updates. We aim to propose reforms to current influenza vaccination policies based on our analysis of cost-effectiveness studies. This cross-sectional epidemiological study used influenza case, death, discharge and hospitalization data from several influenza seasons and applied a one-year decision-analytic model to assess cost-effectiveness. The primary health outcome was influenza cases avoided; secondary health outcomes were influenza-related events associated with case reduction. By increasing vaccination coverage to 75% in the population aged 12-49 years with risk factors (diabetes, high blood pressure, morbid obesity, chronic renal failure, asthma, pregnancy), and expanding universal vaccination coverage to school-aged children (5-11 years) and adults aged 50-59 years, 7142-671,461 influenza cases; 1-15 deaths; 7615-262,812 healthcare visits; 2886-154,143 emergency room admissions and 2891-97,637 hospitalizations could be prevented (ranges correspond to separate age and risk factor groups), with a net annual savings of 3.90 to 111.99 million USD. Such changes to the current vaccination policy could potentially result in significant economic and health benefits. These data could be used to inform the revision of a vaccination policy in Mexico with substantial social value.

Seasonal Influenza Vaccine: Uptake, Attitude, and Knowledge Among Patients Receiving Immunoglobulin Replacement Therapy

Influenza is a potential cause of severe disease in the immunocompromised. Patients with hypogammaglobulinemia, in spite of adequate replacement therapy, are at risk of significant morbidity and adverse outcomes. A seasonal vaccine is the primary prophylactic countermeasure to limit disease. The aim of this study was to evaluate the attitude, knowledge, and influenza vaccine uptake among Irish patients receiving immunoglobulin replacement therapy (IgRT), as well as uptake in co-habitants. Fifty-seven percent of patients receiving IgRT at a regional immunology referral center completed a questionnaire evaluation. Seventy-six percent of IgRT patients received the influenza vaccine for the 2019 season. Ninety-eight percent recognized that influenza could be prevented with vaccination, and 81% deemed it a safe treatment. Ninety-three percent correctly identified that having a chronic medical condition, independent of age, was an indication for vaccination. Despite excellent compliance and knowledge, many were not aware that vaccination was recommended for co-habitants, and only 24% had full vaccine coverage at home. Those who received advice regarding vaccination of household members had higher rates of uptake at home. This study demonstrates awareness and adherence to seasonal influenza vaccine recommendations among patients receiving IgRT. Over three quarters felt adequately informed, the majority stating physicians as their information source. We identified an easily modifiable knowledge gap regarding vaccination of household members. This data reveals a need to emphasize the importance of vaccination for close contacts of at-risk patients, to maintain optimal immunity and health outcome.

Cost-Effectiveness of Routine Childhood Vaccination Against Seasonal Influenza in Germany

OBJECTIVES

In Germany, routine influenza vaccination with quadrivalent influenza vaccines (QIV) is recommended and reimbursed for individuals ≥60 years of age and individuals with underlying chronic conditions. The present study examines the cost-effectiveness of a possible extension of the recommendation to include strategies of childhood vaccination against seasonal influenza using QIV.

METHODS

A dynamic transmission model was used to examine the epidemiological impact of different childhood vaccination strategies. The outputs were used in a health economic decision tree to calculate the costs per quality-adjusted life year (QALY) gained from a societal and a third-party payer (TPP) perspective. Strain-specific epidemiology, vaccine uptake, and vaccine efficacy data from the 10 non-pandemic seasons from 2003/2004 to 2013/2014 were used, and cost data were drawn mainly from a health insurance claims data analysis and supplemented by estimates from literature. Uncertainty is explored via scenario, deterministic, and probabilistic sensitivity analyses.

RESULTS

Vaccinating 2- to 9-year-olds with QIV assuming a vaccine uptake of 40% is cost-saving with a benefit-cost ratio of 1.66 from a societal perspective and an incremental cost-effectiveness ratio of €998/QALY from a TPP perspective. Lower and higher vaccine uptakes show marginal effects, while extending the target group to 2- to 17-year-olds further increases the health benefits while still being below the willingness-to-pay (WTP) threshold. Assuming no vaccine-induced herd protection has a negative effect on the cost-effectiveness ratio, but childhood vaccination remains cost-effective.

CONCLUSION

Routine childhood vaccination against seasonal influenza in Germany is most likely to be cost-saving from a societal perspective and highly cost-effective from a TPP perspective.

It runs in the family - Influenza vaccination and spillover effects

We study a population-based influenza vaccination program in the Netherlands, and the spillovers it has within families. Individuals aged 65 years and over qualify for the program and receive a personal invitation for a free flu shot, while ineligible individuals have to pay out-of-pocket and face additional barriers to getting vaccinated. The quasi-random variation at age 65 is exploited to analyse program impact on vaccination behavior of cohabiting partners and adult children. We find that the program induced a 10 percentage points increase in vaccination coverage among individuals at age 65. The program further led to a similar effect on vaccination take-up by cohabiting younger partners, but spillovers on children were negative. These asymmetric patterns of vaccination uptake are consistent with partners and children learning about influenza mortality risk, target group membership, and cost and benefits of vaccination, as well as salience. We conclude that public health campaigns should pay attention to the effects on voluntary preventive care participation as within-family spillovers impact the program's overall public health impact.

Attitudes and Perception of Healthcare Workers Concerning Influenza Vaccination during the 2019/2020 Season: A Survey of Sicilian University Hospitals

Influenza is an infectious disease with a high impact on the population in terms of morbidity and mortality, but despite International and European guidelines, vaccination coverage rates among healthcare workers (HCWs) remain very low. The aim of the present study was to evaluate influenza vaccination adherence in the three Sicilian University Hospitals of Catania, Messina, and Palermo and to understand the attitudes and perceptions of vaccinated healthcare workers and the main reasons for vaccination refusal. A cross-sectional survey through a self-administered questionnaire was conducted during the 2019/2020 influenza season. Overall, 2356 vaccinated healthcare workers answered the questionnaire. The main reason reported for influenza vaccination adherence during the 2019/2020 season was to protect patients. Higher self-perceived risk of contracting influenza and a positive attitude to recommending vaccination to patients were significantly associated with influenza vaccination adherence during the last five seasons via multivariable analysis. Fear of an adverse reaction was the main reason for influenza vaccine refusal. In accordance with these findings, Public Health institutions should develop and tailor formative and informative campaigns to reduce principal barriers to the immunization process and promote influenza vaccination adherence among HCWs.

Incidence of community-acquired pneumonia in urban China: A national population-based study

BACKGROUND

Community-acquired pneumonia (CAP) is one of the major global health problems worldwide. However, the epidemiological information of CAP is limited in China. This study aimed to estimate the incidence rate of CAP and describe the epidemiologic characteristics among the Chinese population.

METHODS

We conducted a retrospective analysis of CAP incidence using the Chinese Urban Basic Medical Insurance database of 23 provinces in 2016, which covered 427.52 million urban beneficiaries of all age groups in Mainland China. CAP episodes were identified using a diagnosis-term-derived algorithm, and multiple CAP records of one single person within 90 continuous days were considered as one single episode. The incidence rates were calculated and described by sex, age, region, and season.

RESULTS

A total of 1.42 million patients were identified as having one or more CAP episodes, and finally a sum of 1.48 million CAP episodes were counted. The overall incidence of CAP was 7.13 (95% CI: 6.11-8.15) per 1000 person-years, in males 7.32 (95% CI: 6.28-8.35) and females 6.93 (95% CI: 5.92-7.94) per 1000 person-years, respectively. The incidence varied by age with a U-shaped curve peaking in children aged < 5 years old [65.80 (95% CI: 62.52-69.08)] and elderly population aged ≥ 80 years old [14.98 (95% CI: 13.63-16.34)]. The incidence varied markedly by regions. Furthermore, the rate showed a clear seasonal trend, which peaked in spring, decreased in summer and autumn, and re-ascended in winter.

CONCLUSION

This study reveals a relatively high level of CAP incidence in China. These findings provide baseline data for establishing effective prevention strategies, targeted at susceptible populations, regions, and seasons in China.

Influenza vaccination among infection control teams: A EUCIC survey prior to COVID-19 pandemic

We aimed to describe the influenza vaccination rate and its determinants among infection control team (ICT) across different countries. Online multilingual survey consisting of 23 items, between 17 May -15 July of 2019 targeting the opinions and practices of ICTs regarding the 2018-2019 influenza season was employed. Participants were reached via European Society of Clinical Microbiology and Infectious Diseases (ESCMID) and European Union Certificate for Infection Control (EUCIC) newsletters,social media, and national societies. In total, 899 participants from 56 countries responded to the survey. The overall vaccination rate was 76%, being the highest in Finland, Portugal, Norway, and Israel (100%), whereas the lowest in Italy (68%) and Turkey (39%). Influenza vaccination rate was 86% among IC physicians and 52% among IC nurses. The most significant factors affecting participants' decision were personal influenza vaccine experience (49%) and attitude of the scientific authorities (48%). In multivariate analysis, vaccination of the ICT head (OR: 16.04, 95%CI: 8.4-30.8, p < 0.001) and having free vaccine (OR: 7.56, 95%CI: 2.1-27.4, p = 0.02) were found to be the strongest predictors for influenza vaccination, whereas working in Turkey (OR: 0.41, 95%CI: 0.22-0.77, p = 0.006) and being an IC nurse (OR:0.43, 95%CI: 0.24-0.80, p = 0.007) were significantly associated with not having been vaccinated. In conclusion, COVID-19 pandemic increased the importance of protection against respiratory viruses including influenza. Vaccination strategies should have a special emphasis on IC nurses, who have a relatively lower vaccination rate, should enhance the vaccination of the ICT leaders, and put effort to provide free availability of the influenza vaccine.

Acceptability of Vaccination Against COVID-19 Among Healthcare Workers in the Democratic Republic of the Congo

PURPOSE

This study aims to estimate the acceptability of a future vaccine against COVID-19 and associated factors if offered in Congolese health-care workers (HCWs), since they have the highest direct exposure to the disease.

PATIENTS AND METHODS

We conducted an analytical cross-sectional study among 23 Congolese referral hospitals, including three university hospitals, located in three towns from March through 30 April 2020. The main outcome variable was healthcare workers' acceptance of a future vaccine against COVID-19. The associated factors of vaccination willingness were identified through a logistic regression analysis.

RESULTS

A sample of 613 HCWs participated in the study and completed the study questionnaire, including 312 (50.9%) men and 301 (49.1%) women. Only 27.7% of HCWs said that they would accept a COVID-19 vaccine if it was available. From the logistic regression analysis, male healthcare workers (ORa=1.17, 95% CI: 1.15-2.60), primarily doctors (ORa=1.59; 95% CI:1.03-2.44) and having a positive attitude towards a COVID-19 vaccine (ORa=11.49; 95% CI: 5.88-22.46) were significantly associated with reporting willingness to be vaccinated.

CONCLUSION

For acceptability of vaccination against COVID-19 among others education among HCWs is crucial because health professionals' attitudes about vaccines are an important determinant of their own vaccine uptake and their likelihood of recommending the vaccine to their patients.

Low rates of influenza vaccination uptake among healthcare workers: Distinguishing barriers between occupational groups

BACKGROUND

To gain further insights into health care workers (HCWs) attitudes toward influenza vaccination to guide future interventions to increase vaccination rates.

METHODS

A standardized anonymous questionnaire was sent to all employees of the University Hospital Basel, Switzerland following the influenza season 2013/2014. We collected information regarding HCW's demographics, experiences with flu vaccinations, and reasons for nonvaccination.

RESULTS

Vaccination rates ranged from 14.7% to 31% from 2007 to 2019. A total of 1,454 HCW participated in the survey, of which 62% reported being vaccinated. HCW not vaccinated were more commonly female and differed by occupational group and department. The main reasons for nonvaccination were fear of short-term adverse reactions, followed by assessing the evidence regarding vaccination-benefits as insufficient and fears of violation of the right to self-determination. Fear of long-term sequela and violation of the right of self-determination differed between the 4 professional groups, both being most commonly indicated by nurses and at least indicated by physicians.

CONCLUSIONS

This study provides some insight into differences regarding barriers to vaccination between different occupational groups, which might not have been adequately addressed so far. Policy makers should consider such differences when designing campaigns to raise acceptance of influenza vaccine among HCWs.

Impact of influenza vaccination programmes among the elderly population on primary care, Portugal, Spain and the Netherlands: 2015/16 to 2017/18 influenza seasons

Background

To increase the acceptability of influenza vaccine, it is important to quantify the overall benefits of the vaccination programme.

Aim

To assess the impact of influenza vaccination in Portugal, Spain and the Netherlands, we estimated the number of medically attended influenza-confirmed cases (MAICC) in primary care averted in the seasons 2015/16 to 2017/18 among those ≥ 65 years.

Methods

We used an ecological approach to estimate vaccination impact. We compared the number of observed MAICC (n) to the estimated number that would have occurred without the vaccination programme (N). To estimate N, we used: (i) MAICC estimated from influenza surveillance systems, (ii) vaccine coverage, (iii) pooled (sub)type-specific influenza vaccine effectiveness estimates for seasons 2015/16 to 2017/18, weighted by the proportion of virus circulation in each season and country. We estimated the number of MAICC averted (NAE) and the prevented fraction (PF) by the vaccination programme.

Results

The annual average of NAE in the population ≥ 65 years was 33, 58 and 204 MAICC per 100,000 in Portugal, Spain and the Netherlands, respectively. On average, influenza vaccination prevented 10.7%, 10.9% and 14.2% of potential influenza MAICC each season in these countries. The lowest PF was in 2016/17 (4.9–6.1%) with an NAE ranging from 24 to 69 per 100,000.

Conclusions

Our results suggest that influenza vaccination programmes reduced a substantial number of MAICC. Together with studies on hospitalisations and deaths averted by influenza vaccination programmes, this will contribute to the evaluation of the impact of vaccination strategies and strengthen public health communication.

Trends, Coverage and Influencing Determinants of Influenza Vaccination in the Elderly: A Population-Based National Survey in Spain (2006-2017)

Influenza is a significant public health problem and the elderly are at a greater risk of contracting the disease. The vaccination coverage of the elderly is below the Spanish target of 65% for each influenza season. The aims of this study were to report the coverage of influenza vaccination in Spain among the population aged ≥65 years and high-risk groups for suffering chronic diseases, to analyze the time trends from 2006 to 2017 and to identify the factors which affect vaccination coverage. A nationwide cross-sectional study was conducted including 20,753 non-institutionalized individuals aged ≥65 years who had participated in the Spanish National Health Surveys in 2006, 2011/2012, and 2017. Sociodemographic, health-related variables, and influenza vaccination data were used. A logistic regression analysis was performed to determine the variables associated with influenza vaccination. Influenza vaccination coverage was 60%. By chronic condition, older people with high cholesterol levels and cancer had the lowest vaccination coverage (62.41% and 60.73%, respectively). This coverage declined from 2006 to 2017 in both groups. Higher influenza vaccination was associated with males, Spanish nationality, normal social support perceived, polypharmacy, worse perceived health, participation in other preventive measures, and increasing age and the number of chronic diseases.

Impact of Influenza Vaccination on All-Cause Mortality and Hospitalization for Pneumonia in Adults and the Elderly with Diabetes: A Meta-Analysis of Observational Studies

Diabetes is a chronic condition that can be worsened by complications such as seasonal influenza virus infections. The aim of the present meta-analysis is the systematic retrieval and analysis of all available evidence on the effects of an influenza vaccine on diabetic patients. We conducted a systematic review and meta-analysis by searching MEDLINE, Embase and the Cochrane databases from inception until April 2019. We included all types of studies reporting on the effectiveness of influenza vaccination in adult and elderly patients with type 1 and type 2 diabetes. The Newcastle-Ottawa scale was used to assess risk of bias, the GRADE methodology was used to assess the evidence for each outcome. A total of 2261 studies were identified, of those, 6 studies completely fulfilled the inclusion criteria. In the 6 studies included in the analysis, influenza vaccination was associated with a lower mortality rate (Mantel Haenszel Odds Ratio (MH-OR), 95% CI: 0.54 (0.40; 0.74), p < 0.001). Patients who received influenza vaccination showed a lower risk of hospitalization for pneumonia (MH-OR, 95% CI: 0.89; (0.80; 0.98), p = 0.18). A sensitivity analysis using fixed effect model confirmed the results (MH-OR, 95% CI: 0.91; (0.87; 0.96); p = 0.001). The results of this meta-analysis are clinically relevant and support the recommendation for all persons with diabetes to receive influenza vaccination.

Surveillance of medically-attended influenza in elderly patients from Romania-data from three consecutive influenza seasons (2015/16, 2016/17, and 2017/18)

Background

Influenza is an acute infection affecting all age groups; however, elderly patients are at an increased risk. We aim to describe the clinical characteristics and the circulation of influenza virus types in elderly patients admitted for severe acute respiratory infection (SARI) to a tertiary care hospital in Bucharest, Romania, part of the I‐MOVE+ hospital network.

Methods

We conducted an active surveillance study at the National Institute for Infectious Diseases “Prof. Dr Matei Balș,” Bucharest, Romania, during three consecutive influenza seasons: 2015/16, 2016/17, and 2017/18. All patients aged 65 and older admitted to our hospital for SARI were tested for influenza by PCR.

Results

A total of 349 eligible patients were tested during the study period, and 149 (42.7%) were confirmed with influenza. Most patients, 321 (92.5%) presented at least one underlying condition at the time of hospital admission, the most frequent being cardiovascular disease, 270 (78.3%). The main influenza viral subtype circulating in 2015/16 was A(H1N1)pdm09, followed by A(H3N2) in 2016/17 and B influenza in 2017/18. Case fatality was highest in the 2015/16 season (3.7%), 0% in 2016/17, and 1.0% in 2017/18. Vaccination coverage in elderly patients with SARI from our study population was 22 (6.3%) over the three seasons.

Conclusions

Our study has highlighted a high burden of comorbidities in elderly patients presenting with SARI during winter season in Romania. The influenza vaccine coverage rate needs to be substantially increased in the elderly population, through targeted interventions.

Influenza vaccination among Dutch general practitioners and their attitude toward influenza vaccination in the elderly

Knowledge, attitudes and beliefs (KABs) toward influenza vaccination (IV) play a key role in HCWs’ decisions to receive vaccination and can strongly influence patients’ IV uptake. We examined the knowledge, attitudes and beliefs of GPs toward IV, exploring their opinion on IV in the elderly, mandatory HCW vaccination and the desirability of an IV trial in the elderly with hospitalization/mortality as effect measure. From November 2018 to March 2019, surveys were emailed to GPs and GP-practices (n = 1676) in three regions of the Netherlands. We assessed the self-reported IV in GPs, reasons for (not) advising IV to personnel, (not) supporting mandatory IV for personnel and (not) desiring a trial on IV in the elderly on hospitalization/mortality. Multivariable logistic regression models were used to determine predictors for GP IV. A total of 552 surveys were completed and 71.9% of the GPs reported receiving IV. Determinants for IV in GPs were male sex (aOR 1.62, 95%CI 1.06–2.49, p = .03) and age ≥60 y (aOR 5.25, 95%CI 1.51–18.32, p = .01). Seventy-nine percent of the GPs recommend IV for their practice personnel. Mandatory IV for personnel was supported by 41.2% of the GPs with GP self-reporting IV being the only determinant (aOR 10.03 (95%CI 5.69–17.70 p = .00)). An IV trial on hospitalization and/or mortality was desired by 60.5% of the GPs. We concluded that the majority of Dutch GPs receives IV and recommends IV to their personnel. These high rates along with the hesitancy of GPs toward mandatory HCW IV should be considered when policymakers decide on a mandate for IV in HCW in general.

Barriers to seasonal influenza vaccine uptake among health care workers in long-term care facilities: A cross-sectional analysis

Objectives The vaccination of health care workers (HCWs) against influenza is recommended by numerous public health authorities. Despite these recommendations, the rate of vaccine uptake is poor, particularly among those working in long-term care. The current study aimed to use the theoretical domains framework to identify the barriers associated with influenza vaccine uptake among HCWs in long-term care facilities. Design The study employed a cross-sectional survey design. Methods HCWs (n = 372) at 21 long-term care facilities in the west of Ireland completed a paper-based questionnaire, which assessed the socio-demographic and psychosocial determinants associated with HCW influenza vaccine uptake. Results Findings indicated that a logistic regression using the theoretical domains framework demonstrated a strong ability to correctly classify whether or not HCWs received the influenza vaccine. Significant predictors of receiving the vaccine were past vaccination (OR = 16.16, 95% CI = 5.52-47.34), Goals (OR = 3.15, 95% CI = 1.63-6.06), Intentions (OR = 2.42, 95% CI = 1.23-4.77), Social influences (OR = 0.39, 95% CI = 0.18-0.84), and Reinforcement (OR = 0.46, 95% CI = 0.21-0.98). Conclusions This research identified the key psychological determinants associated with HCW vaccine uptake. Interventions that target the theoretical domains, Goals, Intentions, Social influences, and Reinforcement, may enhance vaccine uptake among HCW in long-term care facilities. Statement of contribution What is already known on this subject? Seasonal influenza vaccine uptake among health care workers in long-term care settings is suboptimal. Many socio-demographic, psychosocial, and organizational barriers to vaccination have been identified. However, few studies have explored the barriers to vaccination among health care workers in long-term care settings within a behaviour change theory framework. What does this study add? This is the first study to apply the theoretical domains framework to vaccination behaviour. Health care worker vaccine uptake was associated with having previously received the vaccine and the domains Goals, Intentions, Social influences, and Reinforcement. The findings suggest that interventions that target these domains may increase vaccine uptake among health care workers in long-term care facilities. Possible interventions could include vaccination action planning and promoting vaccination as a positive act rather than a professional responsibility.

The Dutch influenza vaccination policy and medication use, outpatient visits, hospitalization and mortality at age 65

Background

Our objective was to obtain estimates of the impact of the Dutch vaccination programme on medication use, outpatient visits, hospitalization and mortality at age 65.

Methods

We linked population-wide mortality, hospitalization and municipality registries to identify influenza-related deaths and hospitalizations, and used health interview surveys to identify medication use and outpatient visits during 1996–2008. We applied a regression discontinuity design to estimate the intention-to-treat effect of the personal invitation for a free influenza vaccination sent to every Dutch inhabitant at age 65 years on each of the outcomes, separately in influenza-epidemic and non-epidemic months.

Results

Invitation receipt for free influenza vaccination at age 65 led to a 9.8 percentage points [95% confidence interval (CI) = 3.5 to16.1; P < 0.01] rise in influenza vaccination. During influenza-epidemic months, it was associated with 1.5 fewer influenza/pneumonia deaths per 100 000 individuals (95% CI = −3.1 to −0.0; P = 0.05), a 15 percentage point lower probability to use prescribed medicines (95% CI = −28 to −3; P = 0.02) and 0.13 fewer General Practitioner (GP) visits per month (95% CI = −0.28 to 0.02; P = 0.09), while the association with hospitalizations due to influenza/pneumonia was small and imprecisely estimated (seven more hospitalizations per 100 000 individuals, 95% CI = −20 to 33; P = 0.63). No associations were found with any outcomes during non-epidemic months.

Conclusions

Personal invitations for a free influenza vaccination sent to every Dutch inhabitant at age 65 took pressure off primary health care but had small effects on hospitalizations and mortality.

Antibody Responses to Influenza A/H1N1pdm09 Virus After Pandemic and Seasonal Influenza Vaccination in Healthcare Workers: A 5-Year Follow-up Study

Background

The 2009 influenza pandemic was caused by the A/H1N1pdm09 virus, which was subsequently included in the seasonal vaccine, up to 2016/2017, as the A/H1N1 strain. This provided a unique opportunity to investigate the antibody response to H1N1pdm09 over time.

Methods

Healthcare workers (HCWs) were immunized with the AS03-adjuvanted H1N1pdm09 vaccine in 2009 (N = 250), and subsequently vaccinated with seasonal vaccines containing H1N1pdm09 for 4 seasons (repeated group), <4 seasons (occasional group), or no seasons (single group). Blood samples were collected pre and at 21 days and 3, 6, and 12 months after each vaccination, or annually (pre-season) from 2010 in the single group. The H1N1pdm09-specific antibodies were measured by the hemagglutination inhibition (HI) assay.

Results

Pandemic vaccination robustly induced HI antibodies that persisted above the 50% protective threshold (HI titers ≥ 40) over 12 months post-vaccination. Previous seasonal vaccination and the duration of adverse events after the pandemic vaccination influenced the decision to vaccinate in subsequent seasons. During 2010/2011-2013/2014, antibodies were boosted after each seasonal vaccination, although no significant difference was observed between the repeated and occasional groups. In the single group without seasonal vaccination, 32% of HCWs seroconverted (≥4-fold increase in HI titers) during the 4 subsequent years, most of whom had HI titers <40 prior to seroconversion. When excluding these seroconverted HCWs, HI titers gradually declined from 12 to 60 months post-pandemic vaccination.

Conclusions

Pandemic vaccination elicited durable antibodies, supporting the incorporation of adjuvant. Our findings support the current recommendation of annual influenza vaccination in HCWs.

Clinical Trials Registration

NCT01003288.

Strategies to Increase Flu Vaccination Coverage among Healthcare Workers: A 4 Years Study in a Large Italian Teaching Hospital

Flu vaccination is recommended among healthcare workers (HCWs). The low vaccination coverage registered in our hospital among HCWs called for new engaging approaches to improve flu vaccination coverage. The aim of this study was to evaluate the efficacy of different strategies implemented during the last four years (2015-2019). A quasi-experimental study was conducted, involving almost 4000 HCWs each year. Starting from the 2015-2016 campaign, new evidence-based strategies were progressively implemented. At the end of each campaign, an evaluation of the vaccination coverage rate reached was performed. Moreover, during the last three campaigns, differences in coverage among job category, wards involved or not in on-site vaccination (OSV) intervention, age classes and gender were analyzed. An increasing flu vaccination coverage rate was registered, from 6% in 2015-2016 to almost 22% at the end of 2018-2019. The overall number of vaccinated HCWs increased, especially at younger ages. OSV strategy always leads to better results, and physicians always show a higher vaccination coverage than nurses and other HCWs. The implemented strategies were effective in achieving higher flu vaccination coverage among HCWs in our hospital and therefore can be considered valuable examples of good prevention practices in hospital settings.

Hospital-acquired influenza infections detected by a surveillance system over six seasons, from 2010/2011 to 2015/2016

Background

In addition to outbreaks of nosocomial influenza, sporadic nosocomial influenza infections also occur but are generally not reported in the literature.

This study aimed to determine the epidemiologic characteristics of cases of nosocomial influenza compared with the remaining severe cases of severe influenza in acute hospitals in Catalonia (Spain) which were identified by surveillance.

Methods

An observational case-case epidemiological study was carried out in patients aged ≥18 years from Catalan 12 hospitals between 2010 and 2016. For each laboratory-confirmed influenza case (nosocomial or not) we collected demographic, virological and clinical characteristics. We defined patients with nosocomial influenza as those admitted to a hospital for a reason other than acute respiratory infection in whom ILI symptoms developed ≥48 h after admission and influenza virus infection was confirmed using RT-PCR. Mixed-effects regression was used to estimate the crude and adjusted OR.

Results

One thousand seven hundred twenty-two hospitalized patients with severe laboratory-confirmed influenza virus infection were included: 96 (5.6%) were classified as nosocomial influenza and more frequently had > 14 days of hospital stay (42.7% vs. 27.7%, P < .001) and higher mortality (18.8% vs. 12.6%, P < .02). The variables associated with nosocomial influenza cases in acute-care hospital settings were chronic renal disease (aOR 2.44 95% CI 1.44–4.15) and immunodeficiency (aOR 1.79 95% CI 1.04–3.06).

Conclusions

Nosocomial infections are a recurring problem associated with high rates of chronic diseases and death. These findings underline the need for adherence to infection control guidelines.

[Insufficient influenza vaccination coverage in giant cell arteritis. A French population-based study]

PURPOSE

To evaluate the rate of seasonal influenza vaccination coverage (IVC) in incident giant cell arteritis (GCA) patients compared with controls.

METHODS

The vaccination rate was estimated from vaccine dispensation. IVC was compared between GCA and their controls using longitudinal multivariate Poisson regression.

RESULTS

During the influenza campaigns from 2005-2006 to 2010-2011, the IVC rates in the GCA group and the control group ranged from 60.8 to 74.7% vs. 56.6 to 70.4%, respectively. Incident GCA influenza vaccination rate was 20% higher than controls (RR=1.20 ; IC 1.09 to 1.32, P<0.001).

CONCLUSION

Although suboptimal, IVC in incident GCA was statistically better than controls.

Impact of national influenza vaccination strategy in severe influenza outcomes among the high-risk Portuguese population

Background

All aged individuals with a chronic condition and those with 65 and more years are at increased risk of severe influenza post-infection complications. There is limited research on cases averted by the yearly vaccination programs in high-risk individuals. The objective was to estimate the impact of trivalent seasonal influenza vaccination on averted hospitalizations and death among the high-risk population in Portugal.

Methods

The impact of trivalent seasonal influenza vaccination was estimated using vaccine coverage, vaccine effectiveness and the number of influenza-related hospitalizations and deaths. The number of averted events (NAE), prevented fraction (PF) and number needed to vaccinate (NVN) were estimated for seasons 2014/15 to 2016/17.

Results

The vaccination strategy averted on average approximately 1833 hospitalizations and 383 deaths per season. Highest NAE was observed in the ≥65 years population (85% of hospitalizations and 95% deaths) and in the 2016/17 season (1957 hospitalizations and 439 deaths). On average, seasonal vaccination prevented 21% of hospitalizations in the population aged 65 and more, and 18.5% in the population with chronic conditions. The vaccination also prevented 29% and 19.5% of deaths in each group of the high-risk population. It would be needed to vaccinate 3360 high-risk individuals, to prevent one hospitalization and 60,471 high-risk individuals to prevent one death.

Conclusion

The yearly influenza vaccination campaigns had a sustained positive benefit for the high-risk population, reducing hospitalizations and deaths. These results can support public health plans toward increased vaccine coverage in high-risk groups.

Trends in seasonal influenza vaccine coverage of target groups in France, 2006/07 to 2015/16: Impact of recommendations and 2009 influenza A(H1N1) pandemic

Background and aimsSeasonal influenza vaccination (SIV) uptake (SIVU) rates in France are below target. We (i) describe trends in French SIVU over 10 consecutive seasons among different target groups and (ii) examine the effects of the 2009 influenza A(H1N1) pandemic and the publication of new SIV recommendations in 2011 and 2013.MethodsOur study was based on records of vaccines delivered in community pharmacies for a permanent, representative sample of 805,000 beneficiaries of the French National Health Insurance Fund. For the first objective, we analysed SIVU rate trends among ≥ 65 year olds as well as among  < 65 year olds with each of the following conditions: diabetes, respiratory, cardiovascular, neuromuscular, or chronic liver disease. For the second goal, we computed segmented log-binomial regression analyses.ResultsAfter the 2009 pandemic, except for the target group with liver diseases, where the difference was not statistically significant, SIVU fell significantly in all groups during the 2010/11 season, remaining relatively stable until 2015/16 in groups not targeted by new recommendations. Crude SIVU rates in 2015/16 were 48% (43,950/91,794) for ≥ 65 year olds and between 16% (407/2,565) and 29% (873/3,056) for  < 65 year olds depending on their condition. SIVU increased modestly after new recommendations were published, but only in patients newly eligible for a free vaccine voucher.ConclusionsOur results suggest: (i) a prolonged confidence crisis in SIV, initially impelled by the 2009 pandemic vaccination campaign; (ii) that new recommendations are ineffective without additional measures. Interventional research in this field is a priority.

Cross-sectional study on vaccination coverage in newly diagnosed HIV-infected persons in the Czech Republic

OBJECTIVES

Individuals with HIV infection are at an increased risk for a number of infectious diseases, some of which are preventable by vaccination. Unfortunately, little is known about the attitudes of this population group to vaccination, therefore, we decided to find out vaccination coverage against 5 infections among newly diagnosed HIV-infected patients in the Czech Republic.

METHODS

This cross-sectional study was conducted on newly diagnosed patients who started their follow-up care at the HIV Clinic of Na Bulovce Hospital during the two following years. Vaccination history data and results of serological tests were collected from all participants.

RESULTS

Enrolled were 269 HIV-positive subjects (94.1% males) with a mean age of 34.4 years, 64 subjects (23.8%) had tertiary education, 229 (85.1%) were men having sex with men, 32 (11.9%) were heterosexual, and 8 (3.0%) were injection drug users. The mean CD4+ T-lymphocyte count was 556.2/µL, with 149 persons (55.4%) who had a CD4+ T-lymphocyte count &gt; 500/µL, and 68 (25.3%) individuals were late presenters with CD4+ T-lymphocyte count &lt; 350/µL. A vaccination against tetanus was reported by 262 subjects (97.4%), against influenza by 18 subjects (6.7%), against tick-borne encephalitis by 18 subjects (6.7%), against viral hepatitis A by 78 persons (29.0%), and against hepatitis B by 104 subjects (38.7%). For influenza, tick-borne encephalitis and hepatitis A, a significant positive impact of tertiary education was found (p-values &lt; 0.001-0.044). Vaccination coverage against both types of hepatitis was significantly lower in late presenters (p = 0.044 and p = 0.004, respectively).

CONCLUSIONS

Vaccination rates found in our cohort were except tetanus and hepatitis B in young people low, especially for influenza and tick-borne encephalitis. Higher level of education and less advanced HIV infection were associated with higher vaccination rates. To improve this unsatisfactory situation, more attention should be paid to vaccination.

Influenza vaccine effectiveness in reducing severe outcomes over six influenza seasons, a case-case analysis, Spain, 2010/11 to 2015/16

Introduction

When influenza vaccination is ineffective in preventing influenza virus infection, it may still reduce the severity of influenza-associated disease. Here, we estimate the effect of influenza vaccination in preventing severe outcomes e.g. intensive care unit (ICU) admission and death, even though it did not prevent influenza virus infection and subsequent hospitalisation.

Methods

An observational case–case epidemiological study was carried out in 12 sentinel hospitals in Catalonia (Spain) over six influenza seasons 2010/11–2015/16. Cases were individuals with severe laboratory-confirmed influenza virus infection and aged 18 years and older. For each reported case we collected demographic, virological and clinical characteristics. Logistic regression was used to estimate the crude, adjusted odd ratios (aOR) and 95% confidence intervals (CI).

Results

Of 1,727 hospitalised patients included in the study, 799 were female (46.7%), 591 (34.2%) were admitted to the ICU and 223 (12.9%) died. Influenza vaccination uptake was lower in cases that required ICU admission or died (21.2% vs 29.7%, p < 0.001). The adjusted influenza vaccination effectiveness in preventing ICU admission or death was 23% (95% CI: 1 to 40). In an analysis restricted to sex, age group and antiviral treatment, influenza vaccination had a positive effect on disease severity in all age groups and categories.

Conclusions

We found that influenza vaccination reduced the severity of disease even in cases where it did not prevent infection and influenza-associated hospitalisation. Therefore, increased vaccination uptake may reduce complications, ICU admission and death.

Assessment of the belief and attitudes of Iranian healthcare personnel's toward the influenza infection and influenza vaccination

Introduction

Influenza is one of the main public health problems and health care personnels (HCPs) are one of the at-risk groups for this infection. The goal of the current study was to identify the beliefs and attitudes of the Iranian HCPs about influenza and the influenza vaccine.

Methods

This cross-sectional study was performed in a general hospital in Tehran, Iran from January to June 2016. A total of 418 questionnaires were distributed among the HCPs. The Chi² test, linear regression and one-way ANOVA were used for data analysis, α: 0.05 was considered as a statistically significant level. All analyses were performed using the SPSS19 software.

Results

The influenza vaccination coverage was 57.7%; the highest vaccine rate belongs to the allied health professionals (68.2%). Two main causes for avoiding the influenza vaccination were; the “fear of vaccine adverse effects” and the “uncertainty about the vaccine effectiveness”. The linear regression analysis identified that the physicians had the highest belief score, followed by the nurses and the allied health professionals (p < 0.001).

Conclusions

Educational planning on influenza and influenza vaccination is necessary to improve the vaccination coverage and to reduce the influenza mortality and morbidity in susceptible patients.

Using general practice data to monitor influenza vaccination coverage in the medically at risk: a data linkage study

OBJECTIVE

To examine the possibility of using data from a network of Australian General Practices (GPs) to estimate influenza vaccination coverage in Australians medically at risk.

DESIGN

Data electronically extracted from a large national network of Australian GP clinics (MedicineInsight) was analysed for annual influenza vaccination coverage from 2008 to 2014. We compared the results with the 2009 and 2014 Adult Vaccination Survey. We adjusted for differences in the distribution of age, risk groups and provider types.

SETTING

All states in Australia.

PARTICIPANTS

GPs participating in MedicineInsight programme.

INTERVENTIONS

Not applicable.

MAIN OUTCOME MEASURES

Annual vaccination coverage across risk groups as recorded in Adult Vaccination Survey in 2009 and 2014 were compared with vaccination coverage in MedicineInsight. The impact of National Immunisation Programme expansion of free vaccine in 2010 to cover patients aged <65 years with medical risk factors.

RESULTS

The proportion of MedicineInsight patients aged ≥18 years and diagnosed with medical risk factors was higher in 2014 (33.2%), compared with the AVS in 2009 (25%). In 2009, influenza vaccination coverage estimates for those aged 18-64 years with medical risk factors was lower for MedicineInsight patients compared with the AVS (26% vs 36%). There was no evidence of any change in coverage between 2008 and 2014, despite the vaccine being available free of charge to this group from 2010.

CONCLUSION

General practice databases have the potential to help fill the gap in vaccination coverage data in patients with medical risk factors.

Epidemiology and cost of seasonal influenza in Germany - a claims data analysis

Background

Seasonal influenza contributes substantially to the burden of communicable diseases in Europe, especially among paediatric populations and the elderly. The aim of the present study was to estimate the incidence of seasonal influenza in Germany, the probabilities of related complications and the economic burden of influenza per case and on a population level for different age groups.

Methods

Claims data from 2012 to 2014 from > 8 million insured of a large German sick-ness fund were analysed. A matched case control study was used on a sub-sample of 100,000 influenza cases to calculate complication rates for ear infections/acute otitis media (AOM) and community-acquired pneumonia (CAP) as well as resource use and costs for seven age groups.

Results

Incidence of seasonal influenza varies between the years and is highest among infants and children 2 to 5 years of age. AOM is more likely in the younger age groups with up to 14% more patients in the influenza group than in the control group. CAP is more frequently observed in the younger age groups and in influenza patients 60 years and older. The manifestation of one influenza complication (AOM or CAP) significantly in-creases the occurrence of a second complication (AOM or CAP). The economic burden per case is highest in infants (€251.91) and persons over 60 years of age (€131.59).

Conclusion

The burden of influenza is highest among infants and young children, which is also reflected in the economic burden. Influenza related costs per case are nearly double for infants compared to persons over 60 years of age.

Electronic supplementary material

The online version of this article (10.1186/s12889-019-7458-x) contains supplementary material, which is available to authorized users.

Japanese anti- versus pro-influenza vaccination websites: a text-mining analysis

Anti-vaccination sentiment exists worldwide and Japan is no exception. Health professionals publish pro-influenza vaccination messages online to encourage proactive seeking of influenza vaccination. However, influenza vaccine coverage among the Japanese population is less than optimal. The contents of pro- and anti-influenza vaccination websites may contribute to readers' acceptance of one or the other position. We aimed to use a text-mining method to examine frequently appearing content on websites for and against influenza vaccination. We conducted online searches in January 2017 using two major Japanese search engines (Google Japan and Yahoo! Japan). Targeted websites were classified as 'pro', 'anti' or 'neutral' depending on their claims, with author(s) classified as 'health professionals', 'mass media' or 'laypersons'. Text-mining analysis was conducted, and statistical analysis was performed using a chi-squared test. Of the 334 websites analyzed, 13 content topics were identified. The three most frequently appearing content topics on pro-vaccination websites were vaccination effect for preventing serious cases of influenza, side effects of vaccination, and efficacy rate of vaccination. The three most frequent topics on anti-vaccination websites were ineffectiveness of influenza vaccination, toxicity of vaccination, and side effects of vaccination. The main disseminators of each topic, by author classification, were also revealed. We discuss possible tactics of online influenza vaccination promotion to counter anti-vaccination websites.

Web-based analysis of adherence to influenza vaccination among French healthcare workers

BACKGROUND

Influenza is recognized as a public health threat. However, vaccine hesitancy and poor vaccine uptake have been seen in French healthcare workers (HCWs). As a result, authorities have considered implementing mandatory influenza vaccination for HCWs.

OBJECTIVES

This study aimed to describe factors associated with influenza vaccine adherence or non-adherence in French HCWs and to collect their perception about mandatory influenza vaccination.

STUDY DESIGN

In February 2017, during the influenza season, a standardized questionnaire was sent electronically to the professional email addresses of French HCWs. Analyses were performed having collected 3000 responses.

RESULTS

Between February 1 and 16, 2017, a 14-question survey was sent to HCWs professional email addresses. After a two week period had elaspsed, 3000 answers were collected for analysis. Overall, 45.7% of responders reported they had received influenza vaccination in 2016-2017, with statistical differences relating to professional status, age and practice. In addition, 92.2% reported caring for at-risk patients and 62.9% had a community-based practice. Finally, accepting mandatory influenza vaccination was statistically associated with higher age, a higher socio-professional category, and seasonal influenza vaccine uptake, but not with management of at-risk patients.

CONCLUSIONS

Electronically submitted questionnaires are a rapid and easy tool that can be used to describe factors associated with influenza vaccine uptake in HCWs. In our study, differences in receiving influenza vaccination related to age, practice and professional categories, and provided an insight into potential adherence to mandatory influenza vaccination in HCWs. If repeated, these surveys may also monitor the evolution of vaccine uptake by professional categories.

Vaccination history as a confounder of studies of influenza vaccine effectiveness

BACKGROUND

Vaccination history may confound estimates of influenza vaccine effectiveness (VE) when two conditions are present: (1) Influenza vaccination is associated with vaccination history and (2) vaccination modifies the risk of natural infection in the following seasons, either due to persisting vaccination immunity or due to lower previous risk of natural infection.

METHODS

Analytic arguments are used to define conditions for confounding of VE estimates by vaccination history. Simulation studies, both with accurate and inaccurate assessment of current and previous vaccination status, are used to explore the potential magnitude of these biases when using different statistical models to address confounding by vaccination history.

RESULTS

We found a potential for substantial bias of VE estimates by vaccination history if infection- and/or vaccination-derived immunity persisted from one season to the next and if vaccination uptake in individuals was seasonally correlated. Full adjustment by vaccination history, which is usually not feasible, resulted in unbiased VE estimates. Partial adjustment, i.e. only by prior season's vaccination status, significantly reduced confounding bias. Misclassification of vaccination status, which can also lead to substantial bias, interferes with the adjustment of VE estimates for vaccination history.

CONCLUSIONS

Confounding by vaccination history may bias VE estimates, but even partial adjustment by only the prior season's vaccination status substantially reduces confounding bias. Misclassification of vaccination status may compromise VE estimates and efforts to adjust for vaccination history.

Maternal Care Providers' Barriers Regarding Influenza and Pertussis Vaccination During Pregnancy in Catalonia, Spain

Objective Maternal care providers (MCPs), obstetrician-gynaecologists and midwives are uniquely placed to increase maternal vaccination acceptance. We aimed to assess their knowledge, attitudes and practices regarding influenza and pertussis vaccination during pregnancy. Methods We conducted an online survey among MCPs working at "Attention to Sexual and Reproductive Health" (ASSIR) Units in Catalonia region. The survey included questions about current recommendations of influenza and pertussis immunization during pregnancy, reasons for not routinely recommending vaccination and several strategies to increase vaccination uptake. Results A total of 194 MCPs completed the survey, 178 (91.8%) were female and 145 (70%) were midwives. Only 61 (31.4%) stated they vaccinated themselves annually against influenza with a significant lower uptake among midwives (26.9%) than obstetrician-gynaecologists (44.9%) (p = 0.03). Overall, 53.6% of MCPs knew influenza vaccine was indicated during first trimester but only 43.3% stated they prescribed it. Almost all MCPs (98.5%) knew pertussis vaccine was recommended and 97.4% stated they prescribed it. The most important vaccination barrier found was the concern related to vaccine adverse events (25.9%) and more midwives than obstetrician-gynaecologists expressed this concern (30.8 vs. 10%) (p = 0.02). The most popular strategies were: including vaccine recommendations in the pregnancy booklet (93.8%) and receiving vaccination training (92.3%). In the adjusted analysis, the only factor significantly associated with MCPs' prescription of influenza vaccine during second/third trimester was having been vaccinated themselves (odds ratio 3.70, 95% confidence interval 1.3-13.2). Conclusions for Practice Implementation of practical tools, continuous training and clear definition of responsibilities regarding vaccination among MCPs may have a significant impact on maternal vaccination coverage.