National seasonal influenza vaccination survey in Europe, 2008

Influence of cantonal health policy frameworks & activities on the influenza vaccination rate in patients with non-communicable diseases in Switzerland

BACKGROUND AND OBJECTIVE

Seasonal influenza may cause serious illness, especially in high-risk populations such as older adults and individuals suffering from non-communicable diseases (NCD) and may be prevented by a vaccination. However, an assessment of the impact of the Swiss legal frameworks and number of health activities on influenza vaccination coverage of the population at the cantonal level is lacking.

METHODS

Two participating healthcare insurers sent out 25,000 semi-structured questionnaires to their subscribers aged 60-85 in five Swiss cantons selected according to the number of health activities and legal framework regarding influenza vaccination and linguistic region. Influenza vaccination coverage of the participants was evaluated and stratified by disease status, age, canton, and linguistic region. Results were compared by cantonal activities, legal framework, and linguistic region.

RESULTS

7,617 valid questionnaires were evaluated from the cantons Aargau, Jura, St. Gallen, Schwyz, and Vaud. 47.9 % stated to have an NCD, with the most frequent being muscle/ skeletal disease (36.7%). Before 2018, 48.6% were vaccinated against influenza, and 35.9% in 2019, with the highest in canton Vaud. In all cantons and in both survey periods, NCD patients and those aged 73-85 had a higher vaccination coverage than participants without NCD, and aged 60-72. There was no difference in the odds of getting an influenza shot based on legal framework. Although a comparison of the number of activities between the German-speaking cantons did not reveal any significant differences, the odds of the participants living in a French-speaking canton getting an influenza vaccination was more likely than those living in a German-speaking canton.

CONCLUSION

There was no association between the investigated cantonal frameworks and number of health activities and influenza vaccination coverage in NCD patients in the selected cantons. However, age, disease status and linguistic region appear to have an influence on vaccination uptake.

Association between Adult Vaccine Hesitancy and Parental Acceptance of Childhood COVID-19 Vaccines: A Web-Based Survey in a Northwestern Region in China

China has initiated the COVID-19 vaccination for children aged 15–17 years since late July 2020. This study aimed to determine the association between adult vaccine hesitancy and parental acceptance of childhood COVID-19 vaccines in a multi-ethnicity area of northwestern China. A web-based investigation was performed with a convenience sampling strategy to recruit the parents aged 20–49 years. In a total of 13,451 valid respondents, 66.1% had received the COVID-19 vaccination, 26.6% were intent to receive, while 7.3% were not intent, with an increasing vaccine hesitancy (p < 0.001). Moreover, vaccination uptake of four common vaccines in their children remained low (29.0% for influenza vaccine, 17.9% for pneumonia vaccine, 10.9% for rotavirus vaccine, 8.0% for Enterovirus-71 vaccine), while overall parental acceptance of childhood COVID-19 vaccines was 50.0% (32.7% for those aged 0–5, 46.6% for 6–10, 73.3% for 11–18; p < 0.001). Vaccination uptake of these four vaccines and parental acceptance of childhood COVID-19 vaccine were negatively associated with adult vaccine hesitancy. In addition, respondents mostly preferred childhood COVID-19 vaccines with weak mild common adverse events (β = 1.993) and no severe adverse events (β = 1.731), demonstrating a positive association with adult vaccine hesitancy. Thus, it warrants specific countermeasures to reduce adult vaccine hesitancy and improve strategies for childhood vaccination.

The disease burden of influenza beyond respiratory illness

Although influenza is primarily considered a respiratory infection and causes significant respiratory mortality, evidence suggests that influenza has an additional burden due to broader consequences of the illness. Some of these broader consequences include cardiovascular events, exacerbations of chronic underlying conditions, increased susceptibility to secondary bacterial infections, functional decline, and poor pregnancy outcomes, all of which may lead to an increased risk for hospitalization and death. Although it is methodologically difficult to measure these impacts, epidemiological and interventional study designs have evolved over recent decades to better take them into account. Recognizing these broader consequences of influenza virus infection is essential to determine the full burden of influenza among different subpopulations and the value of preventive approaches. In this review, we outline the main influenza complications and societal impacts beyond the classical respiratory symptoms of the disease.

[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.

Flu vaccination among older persons: study of knowledge and practices

BACKGROUND

Surveys of older adults' knowledge relative to flu immunization have highlighted its relevance in the improvement of vaccination coverage. The purpose of this study was to estimate the proportion of older persons who have ever been immunized against seasonal flu in the municipality of Vračar (Belgrade, Serbia), assess their knowledge related to flu and flu vaccination, and to determine factors associated with flu immunization.

METHODS

In the period November 2012-January 2013, 480 persons aged above 65 years were recruited at the Community Health Center, of which 354 persons were finally included in the study. Data were collected using a questionnaire. To assess the level of knowledge, correct answers were awarded 1 point. The total knowledge score ranged from 0 to 17 and was divided into three levels: poor (0-4 points), moderate (5-8 points), good (9-13 points), and excellent (14-17 points).

RESULTS

The proportion of ever vaccinated older persons was 47.7%. Of those, one third (29.1%) had been immunized regularly. Most seniors (61.9%) demonstrated good, whereas one third (29.8%) demonstrated excellent level of knowledge. In terms of reasons for non-compliance, the highest proportion of older persons declined vaccination because "they were in good health" (33.5%) and because "they did not believe that vaccine protects from flu" (31.5%). Independent predictors of being ever immunized against seasonal flu were having higher level of education, being more knowledgeable relative to flu vaccination, and taking more medications.

CONCLUSIONS

Our results indicate that health care sector requires well-coordinated promotion campaigns to enhance acceptance of flu vaccination. Organized immunization counseling could provide accurate, evidence-based information in order to transform misbeliefs, prejudice, and negative attitude towards vaccination.

Behavioural consequences of vaccination recommendations: An experimental analysis

Annual vaccination is the most effective way to prevent seasonal influenza. However, globally, the recommendations vary from country to country, ranging from universal recommendations, risk-group-specific recommendations, to no recommendation at all. Due to high diversity both in recommendation practice and country-specific preconditions, it is difficult to determine the effect of different recommendations on vaccine uptake. This incentivised laboratory experiment (N = 288) tests the behavioural consequences of different recommendations in a repeated interactive vaccination game. The participants are part of heterogeneous groups, comprised of low- and high-risk type of players. They receive either a universal, risk-group-specific or no recommendation prior to their vaccination decisions. Results show that individuals are sensitive to the recommendations. In detail, a risk-group-specific recommendation increases vaccine uptake of high-risk types. However, at the same time, it decreases vaccine uptake of low-risk types. The results imply that when the proportion of low-risk types in a population is considerably larger than the high-risk group, a risk-group-specific (vs. universal) recommendation comes at the cost of decreased social benefit of vaccination due to the overall lower vaccine uptake. Policy decision-making should therefore complement epidemiological considerations with potential positive and negative behavioural consequences of vaccination recommendations.

Reasons for non-vaccination: Parental vaccine hesitancy and the childhood influenza vaccination school pilot programme in England

INTRODUCTION

In 2013, the annual influenza immunisation programme in England was extended to children to reduce the burden of influenza, but uptake was sub-optimal at 53.2%.

AIM

To explore the reasons some parents decided not to vaccinate their child against influenza as part of the pilot programme offered in schools.

METHODS

Cross-sectional qualitative study conducted between February and July 2015. 913 parents whose children were not vaccinated against influenza in the school pilots in West Yorkshire and Greater Manchester, England, were asked to comment on their reasons for non-vaccination and invited to take part in a semi-structured interview. 138 parents returned response forms, of which 38 were eligible and interested in participating and 25 were interviewed. Interview transcripts were coded by theme in NVivo.

RESULTS

A third of parents who returned response forms had either vaccinated their child elsewhere, intended to have them vaccinated, or had not vaccinated them due to medical reasons (valid or perceived). Most interviewees were not convinced of the need to vaccinate their child against influenza. Parents expressed concerns about influenza vaccine effectiveness and vaccine side effects. Several parents interviewed declined the vaccine for faith reasons due to the presence of porcine gelatine in the vaccine.

CONCLUSIONS

To significantly decrease the burden of influenza in England, influenza vaccination coverage in children needs to be >60%. Hence, it is important to understand the reasons why parents are not vaccinating their children, and to tailor the communication and immunisation programme accordingly. Our finding that a third of parents, who did not consent to their child being vaccinated as part of the school programme, had actually vaccinated their child elsewhere, intended to have their child vaccinated, or had not vaccinated them due to medical reasons, illustrates the importance of including additional questions or data sources when investigating under-vaccination.

Influenza vaccination prevalence and demographic factors of patients and GPs in primary care in Austria and Croatia: a cross-sectional comparative study in the framework of the APRES project

BACKGROUND

The aim of this study was to compare influenza vaccination coverage rates in Austria and Croatia, countries with missing data in the Eurosurveillance and European Centre for Disease Prevention and Control reports. In addition, we assessed demographic factors of GPs and patients and calculated associations regarding vaccination rates.

METHODS

This cross-sectional study was conducted within the context of thethe appropriateness of prescribing antibiotics in primary health care in Europe with respect to antibiotic resistance (APRES) project. Between November 2010 and July 2011, 40 GP practices attempted to recruit 200 patients to complete questionnaires about their influenza vaccination status and demographics. Statistical analyses included subgroup analyses and logistic regression models.

RESULTS

Data from 7269 patient questionnaires could be analyzed (3309 Austria and 3960 Croatia). The vaccination coverage rates were low (2009/2010: A 18.2 vs. C 20.9%, P < 0.001; 2010/2011: A 13.7 vs. C 18.6%; P < 0.001). The rates were found to be highest in persons aged 65 years and older (2009/2010: A 35.1 vs. C 49.5%, P < 0.001; 2010/2011: A 31.1 vs. C 45.7%, P < 0.001) and lowest in children (2009/2010: A 8.5 vs. C 2.0%, P < 0.001; 2010/2011: A 4.3 vs. C 1.6%, P = 0.002). Besides, demographics in the adjusted regression model for Austria being vaccinated was associated with consulting a female GP (OR, 4.20; P < 0.001) and in Croatia with five or more GP consultations per year (OR, 4.41; P < 0.001).

CONCLUSION

The vaccination coverage rates for Austria and Croatia were low, with the highest rates found in persons aged 65 years and older, showing that public coverage of the vaccination costs might increase vaccination rates. However, other factors seem to be relevant, including the engagement of GPs.

Acceptance of intradermal inactivated influenza vaccines among hospital staff following 2 seasonal vaccination campaigns

After a Canadian hospital's official influenza vaccination campaign concluded in the 2011-2012 and 2012-2013 influenza seasons, study nurses provided additional vaccination mobile cart hours and the added choice of an intradermal injection. An additional 2.1% of staff in the first and 1.4% in the second season were vaccinated during the study with 90-99% preferring the intradermal injection or having no preference. All 13 staff who attempted self-injection with the intradermal vaccine in 2012-2013 were successful on their first attempt. Offering alternatives to intramuscular vaccines may increase rates of vaccination.

A Population-Based, Nationwide Cross-Sectional Study on Influenza Vaccination Status among Cancer Survivors in Korea

Cancer survivors are at increased risk of developing influenza-related complications. The purpose of this study was to investigate the vaccination coverage among cancer survivors in Korea using the Korea National Health and Nutrition Examination Survey (KNHANES). Adult cancer survivors were selected from fourth (2007–2009) and fifth (2010–2012) KNHANES (n = 1156) datasets. General characteristics, cancer-related data, and influenza vaccination status were collected using self-report questionnaires. Chi-square tests and multiple logistic regression analyses were performed to investigate the association between influenza vaccination coverage and associated factors. Overall, 51% of survivors were vaccinated. Vaccine prevalence exceeded 75% in those more than 65 years but was only 26% in survivors aged 19–44. Increasing age, low frequency of alcohol consumption, having poor self-rated health, and having a shorter duration since cancer diagnosis were significant predictors of vaccination status among cancer survivors under 65 years of age. Influenza vaccine coverage remains much lower than recommended among cancer survivors, particularly in the younger age groups. Further study is needed to determine the factors that contribute to the lack of vaccination in cancer survivors, despite their increased risk for influenza.

Health care workers' influenza vaccination: motivations and mandatory mask policy

BACKGROUND

Vaccination of health care workers (HCW) against seasonal influenza (SI) is recommended but vaccination rate rarely reach >30%. Vaccination coverage against 2009 pandemic influenza (PI) was 52% in our hospital, whilst a new policy requiring unvaccinated HCW to wear a mask during patient care duties was enforced.

AIMS

To investigate the determinants of this higher vaccination acceptance for PI and to look for an association with the new mask-wearing policy.

METHODS

A retrospective cohort study, involving HCW of three critical departments of a 1023-bed, tertiary-care university hospital in Switzerland. Self-reported 2009-10 SI and 2009 PI vaccination statuses, reasons and demographic data were collected through a literature-based questionnaire. Descriptive statistics, uni- and multivariate analyses were then performed.

RESULTS

There were 472 respondents with a response rate of 54%. Self-reported vaccination acceptance was 64% for PI and 53% for SI. PI vaccination acceptance was associated with being vaccinated against SI (OR 9.5; 95% CI 5.5-16.4), being a physician (OR 7.7; 95% CI 3.1-19.1) and feeling uncomfortable wearing a mask (OR 1.7; 95% CI 1.0-2.8). Main motives for refusing vaccination were: preference for wearing a surgical mask (80% for PI, not applicable for SI) and concerns about vaccine safety (64%, 50%) and efficacy (44%, 35%).

CONCLUSIONS

The new mask-wearing policy was a motivation for vaccination but also offered an alternative to non-compliant HCW. Concerns about vaccine safety and efficiency and self-interest of health care workers are still main determinants for influenza vaccination acceptance. Better incentives are needed to encourage vaccination amongst non-physician HCW.

Number needed to vaccinate to prevent hospitalizations of pregnant women due to inter-pandemic influenza in Sweden, 2003-2009

BACKGROUND

The evidence of increased risk of severe disease for healthy pregnant women due to inter-pandemic influenza consists mainly of observational studies of health service utilization in USA and Canada. However, these results can be context dependent and estimates in a European setting are sparse. For policy purposes we therefore decided to elucidate the potential value of vaccination in Sweden.

MATERIALS AND METHODS

We conducted a retrospective, register-based study of hospitalizations due to inter-pandemic influenza or respiratory infection attributable to influenza in pregnant women in Sweden. With aggregated data from 2003 to 2009 we assessed the number needed to vaccinate (NNV) to prevent one such hospitalization.

RESULTS

We included on average 96,000 pregnant women/year and identified 9-48 hospitalizations/season fulfilling the case definition. Assuming 80% vaccine effectiveness the NNV was >1,900 pregnant women. The estimate is higher than those found in the USA, Canada, and UK. The difference may be explained by differing methods to estimate NNV, but also differences in propensity to hospitalize and the basic health status of the pregnant women.

CONCLUSIONS

Because of the increased risk associated with influenza A(H1N1)pdm09, vaccination is presently offered to all pregnant women in Sweden, but vaccination against other inter-pandemic influenza types seems disputable. The study illustrates the context dependence of preventive health measures and points to the need for national NNV estimates and international harmonization of study methods for comparisons between countries.

Antibiotic effectiveness: balancing conservation against innovation

Antibiotic effectiveness is a natural societal resource that is diminished by antibiotic use. As with other such assets, keeping it available requires both conservation and innovation. Conservation encompasses making the best use of current antibiotic effectiveness by reducing demand through vaccination, infection control, diagnostics, public education, incentives for clinicians to prescribe fewer antibiotics, and restrictions on access to newer, last-resort antibiotics. Innovation includes improving the efficacy of current drugs and replenishing effectiveness by developing new drugs. In this paper, I assess the relative benefits and costs of these two approaches to maintaining our ability to treat infections.

Annual public health and economic benefits of seasonal influenza vaccination: a European estimate

BACKGROUND

Vaccination is currently the most effective means of preventing influenza infection. Yet evidence of vaccine performance, and the impact and value of seasonal influenza vaccination across risk groups and between seasons, continue to generate much discussion. Moreover, vaccination coverage is below recommended levels.

METHODS

A model was generated to assess the annual public health benefits and economic importance of influenza vaccination in 5 WHO recommended vaccination target groups (children 6 - 23 months of age; persons with underlying chronic health conditions; pregnant women; health care workers; and, the elderly, 65 years of age) in 27 countries of the European Union. Model estimations were based on standard calculation methods, conservative assumptions, age-based and country-specific data.

RESULTS

Out of approximately 180 million Europeans for whom influenza vaccination is recommended, only about 80 million persons are vaccinated. Seasonal influenza vaccination currently prevents an annual average of between 1.6 million and 2.1 million cases of influenza, 45,300 to 65,600 hospitalizations, and 25,200 to 37,200 deaths. To reach the 75% vaccination coverage target set by the EU Council Recommendation in 2009, an additional 57.4 million person would need to be vaccinated in the elderly and other risk groups. By achieving the 75% target rate set in EU-27 countries, average annual influenza- related events averted would increase from current levels to an additional +1.6 to +1.7 million cases, +23,800 to +31,400 hospitalization, +9,800 to +14,300 deaths, +678,500 to +767,800 physician visits, and +883,800 to +1,015,100 lost days of work yearly. Influenza-related costs averted because of vaccination would increase by an additional + €190 to + €226 million yearly, in vaccination target groups.

CONCLUSIONS

Full implementation of current influenza vaccination recommendations of 75% vaccination coverage rate (VCR) in Europe by the 2014-2015 influenza season could immediately reduce an important public health and economic burden.

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)

Since 2008, annual surveys of influenza vaccination policies, practices and coverage have been undertaken in 29 European Union (EU)/ European Economic Area (EEA) countries. After 2009, this monitored the impact of European Council recommendation to increase vaccination coverage to 75% among risk groups. This paper summarises the results of three seasonal influenza seasons: 2008/09, 2009/10 and 2010/11. In 2008/09, 27/29 countries completed the survey; in 2009/10 and 2010/11, 28/29 completed it. All or almost all countries recommended vaccination of older people (defined as those aged ≥50, ≥55, ≥59, ≥60 or ≥65 years), and people aged ≥6 months with clinical risk and healthcare workers. A total of 23 countries provided vaccination coverage data for older people, but only 7 and 10 had data for the clinical risk groups and healthcare workers, respectively. The number of countries recommending vaccination for some or all pregnant women increased from 10 in 2008/09 to 22 in 2010/11. Only three countries could report coverage among pregnant women. Seasonal influenza vaccination coverage during and after the pandemic season in older people and clinical groups remained unchanged in countries with higher coverage. However, small decreases were seen in most countries during this period. The results of the surveys indicate that most EU/EEA countries recommend influenza vaccination for the main target groups; however, only a few countries have achieved the target of 75% coverage among risk groups. Coverage among healthcare workers remained low.

Traditional and new influenza vaccines

The challenges in successful vaccination against influenza using conventional approaches lie in their variable efficacy in different age populations, the antigenic variability of the circulating virus, and the production and manufacturing limitations to ensure safe, timely, and adequate supply of vaccine. The conventional influenza vaccine platform is based on stimulating immunity against the major neutralizing antibody target, hemagglutinin (HA), by virus attenuation or inactivation. Improvements to this conventional system have focused primarily on improving production and immunogenicity. Cell culture, reverse genetics, and baculovirus expression technology allow for safe and scalable production, while adjuvants, dose variation, and alternate routes of delivery aim to improve vaccine immunogenicity. Fundamentally different approaches that are currently under development hope to signal new generations of influenza vaccines. Such approaches target nonvariable regions of antigenic proteins, with the idea of stimulating cross-protective antibodies and thus creating a "universal" influenza vaccine. While such approaches have obvious benefits, there are many hurdles yet to clear. Here, we discuss the process and challenges of the current influenza vaccine platform as well as new approaches that are being investigated based on the same antigenic target and newer technologies based on different antigenic targets.

Indicators of influenza and pneumococcal vaccination in French nursing home residents in 2011

INTRODUCTION

Older adults living in nursing homes (NH) are at high risk of developing influenza and pneumococcal infections. The objectives of this study were to describe vaccination coverage for influenza and pneumococcal among French NH residents and to investigate which NH structure- and organisation-related aspects could impact on vaccination in this population.

METHODS

This study is based on cross-sectional data from 175 French NHs (N=6275 residents), collected in May-July 2011. Residents' vaccination status (yes vs. no) against pneumococcal infection and seasonal influenza was recorded by the NH staff (on the basis of the resident's medical chart). Residents' health-related variables (e.g., co-morbidities) and information on NH structure and internal organisation were recorded by the NH staff. Mixed-effects logistic regressions were performed on influenza and pneumococcal vaccination separately.

RESULTS

Influenza vaccination coverage was high (n=5071, i.e., 80.8% of residents) and relatively well-distributed across NHs, whereas pneumococcal vaccination was low (n=1758, i.e., 28%) and highly variable across facilities. Mixed-effects logistic regressions confirmed that structural and organisational aspects related to the NH functioning impacted vaccination coverage. More precisely, living in a private for profit NH, living in NHs located in low-urban areas, and coordinating physician training increased the odds of receiving pneumococcal vaccine, whereas living in NHs located at high-urban areas decreased this odds. Moreover, the time spent by the coordinating physician in the NH increased the odds of receiving influenza vaccine. Prescriptions re-examination since resident's admission at the NH and the presence of an individualised health care project increased the odds of receiving both influenza and pneumococcal vaccines.

CONCLUSIONS

Our findings suggest that a more standardised approach is needed to improve vaccination coverage against pneumococcal infection in French NH residents.

Adult immunization policies in advanced economies: vaccination recommendations, financing, and vaccination coverage

OBJECTIVES

While many countries have robust child immunization programs and high child vaccination coverage, vaccination of adults has received less attention. The objective of this study was to describe the adult vaccination policies in developed countries.

METHODS

From 2010 to 2011, we conducted a survey of 33 advanced economies as defined by the International Monetary Fund. The survey asked about national recommendations for adults for 16 vaccines or vaccine components, funding mechanisms for recommended adult vaccines, and the availability of adult vaccination coverage estimates.

RESULTS

Thirty-one of 33 (93.9 %) advanced economies responded to the survey. Twelve of 31 (38.7 %) reported having a comprehensive adult immunization schedule. The total number of vaccines or vaccine components recommended for adults ranged from one to 15 with a median of 10. Seasonal influenza (n = 30), tetanus (n = 28), pneumococcal polysaccharide (n = 27), and hepatitis B (n = 27) were the most frequently recommended vaccines or components.

CONCLUSIONS

Approximately two-thirds of survey respondents do not have a comprehensive adult vaccine schedule, and most do not measure vaccination coverage. We found that a funding mechanism is available for most recommended adult vaccines.

A cross-sectional study of factors associated with uptake of vaccination against influenza among older residents in the postpandemic season in Beijing, China

OBJECTIVE

Annually, influenza epidemics are associated with high mortality rates, notably among elderly persons. The aim of the study was to examine the level of influenza vaccine coverage among Chinese residents aged 60 years and older and to examine the demographic, behavioural and lifestyle health factors associated with vaccine receipt.

DESIGN

Cross-sectional study.

SETTING

Beijing, China.

PARTICIPANTS

Stratified sampling was used to recruit participants for this study. A total of 2578 people aged 60 years and older consented to participate in this study. Questionnaires from 2481 participants were valid and were included in the final analysis.

OUTCOME MEASURES

Influenza vaccination status and factors associated with vaccination.

METHODS

In late 2010, a survey was conducted with residents from three urban and three rural districts in Beijing, China. Multivariate logistic regression was performed to detect the factors associated with influenza vaccination.

RESULTS

2481 older people (aged ≥60 years) were included in the final analysis. In 2010, 44% had received the annual influenza vaccine. Lower education level, poor health status of the participant, regular taking exercises and considering that vaccine is the best measure for preventing influenza were associated with influenza vaccination coverage.

CONCLUSIONS

Influenza vaccine coverage in Beijing still remains suboptimal. Further work needs to be undertaken to ascertain whether the methods used to distribute the vaccine are adequate and whether health professionals are appropriately promoting the vaccine.

Influenza and hepatitis B vaccination coverage among healthcare workers in Croatian hospitals: a series of cross-sectional surveys, 2006-2011

BACKGROUND

Healthcare workers (HCWs) are at an increased risk of exposure to and transmission of infectious diseases. Vaccination lowers morbidity and mortality of HCWs and their patients. To assess vaccination coverage for influenza and hepatitis B virus (HBV) among HCWs in Croatian hospitals, we conducted yearly nationwide surveys.

METHODS

From 2006 to 2011, all 66 Croatian public hospitals, representing 43-60% of all the HCWs in Croatia, were included. Statistical analysis was performed using the Kruskal-Wallis analysis of variance, Dunn's multiple comparison analysis and the chi-square test, as appropriate.

RESULTS

The median seasonal influenza vaccination coverage rates in pre-pandemic (2006-2008) seasons were 36%, 25% and 29%, respectively. By occupation, influenza vaccination rates among physicians were 33 ± 21%, 33 ± 22% among graduate nurses, 30 ± 34% among other HCWs, 26 ± 21% among housekeeping and the lowest, 23 ± 17%, among practical nurses (p < 0.01). In 2009-2010 season, seasonal influenza vaccination coverage was 30%, while overall vaccination coverage against pandemic influenza was fewer than 5%. Median vaccination coverage in the post-pandemic seasons of 2010-2011 and 2011-2012 decreased to 15% and 14%, respectively (reduction of 24% and 35%, respectively, p < 0.0001). Meanwhile, the median mandatory HBV vaccination coverage was 98%, albeit with considerable differences according to work setting (range 19-100%) and occupation (range 4-100%).

CONCLUSIONS

We found substantial year-on-year variations in seasonal influenza vaccination rates, with reduction in post pandemic influenza seasons. HBV vaccination is satisfactory compared to seasonal influenza vaccination coverage, although substantial variations by occupation and work setting were observed. These findings highlight the need for national strategies that optimize vaccination coverage among HCWs in Croatian hospitals. Further studies are needed to establish the potential role of mandatory vaccination for seasonal influenza.

A randomized controlled study to evaluate the immunogenicity of a trivalent inactivated seasonal influenza vaccine at two dosages in children 6 to 35 months of age

The trivalent inactivated influenza vaccine Fluarix™ is licensed in the US for adults and children from 3 years old. This randomized observer-blind study (NCT00764790) evaluated Fluarix™ at two doses; 0.25 ml (Flu-25) and 0.5 ml (Flu-50) in children aged 6-35 months. The primary objective was to demonstrate immunogenic non-inferiority vs. a control vaccine (Fluzone®; 0.25 ml). Children received Flu-25 (n = 1107), Flu-50 (n = 1106) or control vaccine (n = 1104) at Day 0 and for un-primed children, also on Day 28. Serum hemagglutination-inhibition titers were determined pre-vaccination and at Day 28 (primed) or Day 56 (un-primed). Non-inferiority was assessed by post-vaccination geometric mean titer (GMT) ratio, (upper 95% confidence interval [CI] ≤ 1.5) and difference in seroconversion rate (upper 95% CI ≤ 10%). Reactogenicity/safety was monitored. The immune response to Flu-50 met all regulatory criteria. Indicated by adjusted GMT ratios [with 95% CI], the criteria for non-inferiority of Flu-50 vs. control vaccine were reached for the B/Florida strain (1.13 [1.01-1.25]) but not for the A/Brisbane/H1N1 (1.74 [1.54-1.98]) or A/Uruguay/H3N2 (1.72 [1.57-1.89]) strains. In children aged 18-35 months similar immune responses were observed for Flu-50 and the control vaccine. Flu-50 induced a higher response than Flu-25 for all strains. Temperature (≥ 37.5°C) was reported in 6.2%, 6.4%, and 6.6% of the Flu-25, Flu-50, and control group, respectively. Reactogenicity/safety endpoints were within the same range for all vaccines. In children aged 6-35 months, immune responses with Flu-50 fulfilled regulatory criteria but did not meet the pre-defined criteria for non-inferiority vs. control. This appeared to be due to differences in immunogenicity in children aged<18 months.

Predictive factors associated with the acceptance of pandemic and seasonal influenza vaccination in health care workers and students in Tuscany, Central Italy

Assessing the beliefs and attitudes of Health Care Workers (HCW) to influenza and influenza vaccination can be useful in overcoming low compliance rates. The purpose of our study is to evaluate the opinion of HCW and students regarding influenza, influenza vaccine and the factors associated with vaccination compliance. A survey was conducted between October 2010 and April 2011 in the Florence metropolitan area. A questionnaire was administered to HCW in three local healthcare units and at Careggi University Teaching Hospital. Students matriculating in health degree programs at Florence University were also surveyed.

The coverage with vaccination against seasonal and pandemic influenza is generally low, and it is lower in students than in HCW (12.5% vs 15% for the seasonal vaccination, 8.5% vs 18% for the pandemic vaccination). Individuals comply with vaccination offer mainly to protect themselves and their contacts. Individuals not receiving vaccination did not consider themselves at risk, had never been vaccinated before or believed that pandemic influenza was not a public health concern. Physicians had the highest compliance to vaccination and women were less frequently vaccinated than men. HCW do not appear to perceive their possible influenza infections as a risk for patients: HCW receive vaccination mainly as a form of personal protection.

Low compliance to vaccination is determined by various factors and therefore requires a multi-faceted strategy of response. This should include short-term actions to overcome organizational barriers, in addition to long-term interventions to raise HCW’s level of knowledge about influenza and influenza vaccination.

Hospital-based cluster randomised controlled trial to assess effects of a multi-faceted programme on influenza vaccine coverage among hospital healthcare workers and nosocomial influenza in the Netherlands, 2009 to 2011

Nosocomial influenza is a large burden in hospitals. Despite recommendations from the World Health Organization to vaccinate healthcare workers against influenza, vaccine uptake remains low in most European countries. We performed a pragmatic cluster randomised controlled trial in order to assess the effects of implementing a multi-faceted influenza immunisation programme on vaccine coverage in hospital healthcare workers (HCWs) and on in-patient morbidity. We included hospital HCWs of three intervention and three control University Medical Centers (UMCs), and 3,367 patients. An implementation programme was offered to the intervention UMCs to assess the effects on both vaccine uptake among hospital staff and patient morbidity. In 2009/10, the coverage of seasonal, the first and second dose of pandemic influenza vaccine as well as seasonal vaccine in 2010/11 was higher in intervention UMCs than control UMCs (all p<0.05). At the internal medicine departments of the intervention group with higher vaccine coverage compared to the control group, nosocomial influenza and/or pneumonia was recorded in 3.9% and 9.7% of patients of intervention and control UMCs, respectively (p=0.015). Though potential bias could not be completely ruled out, an increase in vaccine coverage was associated with decreased patient in-hospital morbidity from influenza and/or pneumonia.

The safety and immunogenicity of trivalent inactivated influenza vaccination: a study of maternal-cord blood pairs in Taiwan

Background

There are little data about adverse effects and immunogenicity of flu vaccine in Asian pregnant women.

Methods

This prospective trial (NCT01514708) enrolled 46 pregnant women who received a single intramuscular dose of trivalent flu vaccine (AdimFlu-S®) containing 15 mcg of hemagglutinin for each strain/0.5 mL from influenza A (H1N1), influenza A (H3N2), and influenza B after the first trimester. Blood samples were collected at day 0 and 28 after vaccination, and at delivery. Cord blood was also collected. Hemagglutination inhibition (HAI) assays were performed to determine seroprotection and seroconversion rates and fold increase in the HAI geometric mean titer (GMT).

Results

Twenty-eight days after vaccination the seroprotection rate against H1N1, H3N2, and influenza B was 91.3%, 84.8% and 56.5%, respectively. The GMT fold increase was 12.8, 8.4, and 4.6 for H1N1, H3N2, and influenza B, respectively. At delivery, both the seroprotection rate (86.4%, 68.2%, and 47.7%) and GMT fold increase (9.4, 5.7 and 3.8) were slightly lower than day 28. The seroprotection rate and GMT fold increase in maternal and cord blood samples were comparable. No significant adverse effects were detected.

Conclusions

Trivalent flu vaccine induces a strong immune response in pregnant women and their infants without adverse effects.

Trial Registration

Clinical Trials. gov NCT01514708

Adherence and factors associated with influenza vaccination among subjects with asthma in Spain

PURPOSE

Influenza has a high morbidity and mortality rate and an increased risk of complications in vulnerable individuals. Children and adults with asthma have a high risk of complications, hospitalisation and even death. The objectives of this study were as follows: to compare influenza vaccination coverage in Spain in a population of asthmatics aged ≥ 16 years with an equivalent population of non-asthmatics; to identify the factors that influence vaccination coverage among patients with asthma; and to compare coverage during the period 2006/2007 with that of 2009/2010.

METHODS

We used data from the 2009 European Health Survey (EHS), which included a population of 22,188 individuals (≥ 16 years of age), of whom 1,669 [7.5 %; 95 % confidence interval (CI), 7.13-7.98] had asthma. The dependent variable was the answer (yes/no) to a question asking whether or not the interviewed person had been vaccinated against seasonal (not pandemic) influenza in the previous season. As independent variables, we analysed socio-demographic characteristics, health-related variables and the use of health care services.

RESULTS

Vaccination coverage was 35.2 % (95 % CI, 32.5-37.9) among asthmatics and 22.1 % (95 % CI, 21.4-22.7) among non-asthmatics (p < 0.001). The probability of being vaccinated is almost twice as high for asthmatics as it is for non-asthmatics [odds ratio (OR), 1.92; 95 % CI, 1.69-2.17]. Among asthmatics, vaccination coverage increased with age, worse self-rated health status and not smoking. No significant change in coverage was observed between the study periods.

CONCLUSIONS

Seasonal influenza vaccination coverage among Spanish asthmatics is lower than desired and has not improved in recent years. Urgent strategies are necessary in order to increase vaccination coverage among asthmatics.

Long-term immunogenicity of the pandemic influenza A/H1N1 2009 vaccine among health care workers: influence of prior seasonal influenza vaccination

Health care workers (HCWs) are at great risk of influenza infection and transmission. Vaccination for seasonal influenza is routinely recommended, but this strategy should be reconsidered in a pandemic situation. Between October 2009 and September 2010, a multicenter study was conducted to assess the long-term immunogenicity of the A/H1N1 2009 monovalent influenza vaccine among HCWs compared to non-health care workers (NHCWs). The influence of prior seasonal influenza vaccination was also assessed with respect to the immunogenicity of pandemic H1N1 influenza vaccine. Serum hemagglutinin inhibition titers were determined prevaccination and then at 1, 6, and 10 months after vaccination. Of the 360 enrolled HCW subjects, 289 participated in the study up to 10 months after H1N1 monovalent influenza vaccination, while 60 of 65 NHCW subjects were followed up. Seroprotection rates, seroconversion rates, and geometric mean titer (GMT) ratios fulfilled the European Union's licensure criteria for influenza A/California/7/2009 (H1N1) at 1 month after vaccination in both the HCWs and NHCWs, without any significant difference. At 6 months after vaccination, the seroprotection rate was more significantly lowered among the NHCWs than among the HCWs (P < 0.01). Overall, postvaccination (1, 6, and 10 months after vaccination) GMTs for A/California/7/2009 (H1N1) were significantly lower among the seasonal influenza vaccine recipients than among the nonrecipients (P < 0.05). In conclusion, HCWs should be encouraged to receive an annual influenza vaccination, considering the risk of repeated exposure. However, prior reception of seasonal influenza vaccine showed a negative influence on immunogenicity for the pandemic A/H1N1 2009 influenza vaccine.

Factors Affecting Medical Students' Uptake of the 2009 Pandemic Influenza A (H1N1) Vaccine

Background. Pandemic influenza vaccination rate amongst healthcare workers in England 2009/2010 was suboptimal (40.3%). Targeting medical students before they enter the healthcare workforce is an attractive future option. This study assessed the H1N1 vaccine uptake rate amongst medical students and factors that influenced this. Methods. Anonymised, self-administered questionnaire at a medical school. Results. The uptake rate amongst 126 medical students offered the vaccine was 49.2% and intended uptake amongst 77 students was 63.6%. Amongst those offered the vaccine, the strongest barriers to acceptance were fear of side effects (67.9%), lack of vaccine information (50.9%), lack of perceived risk (45.3%), and inconvenience (35.8%). Having a chronic illness (OR 3.4 (95% CI 1.2-10.2)), 4th/5th year of study (OR 3.0 (95% CI 1.3-7.1)), and correct H1N1 knowledge (OR 2.6 (95% CI 1.1-6.0)) were positively associated with uptake. Non-white ethnicity was an independent negative predictor of uptake (OR 0.4 (95% CI 0.2-0.8)). Students who accepted the H1N1 vaccine were three times more likely (OR 3.1 (95% CI 1.2-7.7)) to accept future seasonal influenza vaccination. Conclusion. Efforts to increase uptake should focus on routine introduction of influenza vaccine and creating a culture of uptake during medical school years, evidence-based education on vaccination, and improving vaccine delivery.

Burden of paediatric influenza in Western Europe: a systematic review

Background

Influenza illness in children causes significant clinical and economic burden. Although some European countries have adopted influenza immunisation policies for healthy children, the debate about paediatric influenza vaccination in most countries of the European Union is ongoing. Our aim was to summarise influenza burden (in terms of health outcomes and economic burden) in children in Western Europe via a systematic literature review.

Methods

We conducted a systematic literature search of PubMed, EMBASE, and the Cochrane Library (1970-April 2011) and extracted data on influenza burden in children (defined as aged ≤ 18 years) from 50 publications (13 reporting laboratory-confirmed influenza; 37 reporting influenza-like illness).

Results

Children with laboratory-confirmed influenza experienced hospitalisations (0.3%-20%), medical visits (1.7-2.8 visits per case), antibiotic prescriptions (7%-55%), and antipyretic or other medications for symptomatic relief (76%-99%); young children and those with severe illness had the highest rates of health care use. Influenza in children also led to absenteeism from day care, school, or work for the children, their siblings, and their parents. Average (mean or median) length of absence from school or day care associated with confirmed influenza ranged from 2.8 to 12.0 days for the children, from 1.3 to 6.0 days for their siblings, and from 1.3 to 6.3 days for their parents. Influenza negatively affected health-related quality of life in children with asthma, including symptoms and activities; this negative effect was smaller in vaccinated children than in non-vaccinated children.

Conclusions

Influenza burden in children is substantial and has a significant direct impact on the ill children and an indirect impact on their siblings and parents. The identified evidence regarding the burden of influenza may help inform both influenza antiviral use in children and paediatric immunisation policies in European countries.

Review on the impact of pregnancy and obesity on influenza virus infection

A myriad of risk factors have been linked to an increase in the severity of the pandemic H1N1 2009 influenza A virus [A(H1N1)pdm09] including pregnancy and obesity where death rates can be elevated as compared to the general population. The goal of this review is to provide an overview of the influence of pregnancy and obesity on the reported cases of A(H1N1)pdm09 virus infection and of how the concurrent presence of these factors may have an exacerbating effect on infection outcome. Also, the hypothesized immunologic mechanisms that contribute to A(H1N1)pdm09 virus severity during pregnant or obese states are outlined. Identifying the mechanisms underlying the increased disease severity in these populations may result in improved therapeutic approaches and future pandemic preparedness.

Seasonal influenza vaccination knowledge, risk perception, health beliefs and vaccination behaviours of nurses

The relationship between knowledge, risk perceptions, health belief towards seasonal influenza and vaccination and the vaccination behaviours of nurses was explored. Qualified nurses attending continuing professional education courses at a large London university between 18 April and 18 October 2010 were surveyed (522/672; response rate 77·7%). Of these, 82·6% worked in hospitals; 37·0% reported receiving seasonal influenza vaccination in the previous season and 44·9% reported never being vaccinated during the last 5 years. All respondents were categorized using two-step cluster analyses into never, occasionally, and continuously vaccinated groups. Nurses vaccinated the season before had higher scores of knowledge and risk perception compared to the unvaccinated (P<0·001). Nurses never vaccinated had the lowest scores of knowledge and risk perception compared to other groups (P<0·001). Nurses' seasonal influenza vaccination behaviours are complex. Knowledge and risk perception predict uptake of vaccination in nurses.

Limiting severe outcomes and impact on intensive care units of moderate-intermediate 2009 pandemic influenza: role of infectious diseases units

PURPOSE

The rate of severe outcomes of patients with 2009 pandemic (A/H1N1) influenza (2009pI) hospitalized in non-intensive care units (ICUs) has not been defined thus far. This study aims to assess the efficacy of the management of patients with influenza-like illness (ILI) of moderate intermediate severity in an infectious diseases unit (IDU) during the first wave of 2009pI and its influence on the burden of ICUs.

METHODS

All patients hospitalized from October 27, 2009, to February 5, 2010, with ILI were included in this prospective observational study. The IDU was organized and the staff was trained to provide intermediate care; patients were transferred to the ICU only if they required invasive ventilation, extracorporeal membrane oxygenation, or advanced cardiovascular support. Demographic data, clinical presentation, coexisting medical conditions, and laboratory and radiological findings were recorded and analyzed, as well as treatment and outcome data.

RESULTS

Overall, 108 patients (median age 36 years [IQR 27-54], 57.4% males) including 66.7% with ≥ 1 risk factor for severe influenza, 47.2% with confirmed 2009pI by RT-PCR and 63.9% with pneumonia, were enrolled in the study. All subjects received intravenous fluids and 83.3% were administered oseltamivir, 96.3% antibacterials, 19.4% oxygen therapy without ventilatory support, and 10.2% non-invasive ventilation. A total of 106 (98.1%) subjects were discharged after a 6-day median hospital stay [IQR 4-9]. Two patients (1.9%) were transferred to the ICU. There were no deaths.

CONCLUSIONS

These results suggest that the aggressive treatment of patients with moderate intermediate severity 2009 pandemic ILI in non-ICU wards may result in a low rate of severe outcomes and brief hospitalization. IDUs, if properly organized for intermediate care, may efficiently provide correct disease management, in addition to complying with infection control requirements, thus reducing the burden of the pandemic on ICUs. Further studies are warranted to evaluate the outcome of patients with moderate intermediate 2009pI in different non-ICU settings.

Can infants be protected by means of maternal vaccination?

The administration of vaccines is not usually recommended in pregnant women because of a fear of severe adverse events for the fetus. However, contraindication to vaccination applies only to vaccines based on live attenuated viruses for the theoretical possibility that they might infect the fetus. In contrast, the use of several inactivated vaccines is useful and recommended. As a result of the transplacental passage of antibodies, maternal immunization can reduce the risk of vaccine-preventable diseases that may occur in the first months of life before the start or completion of the suggested vaccination schedule. One of the best examples is vaccination against influenza that can protect pregnant women from a disease that can lead to hospitalization and death in a significantly higher number of cases than in the general population and can induce protective specific antibody levels as well as being effective in infants in the first months of life. Other examples are vaccinations against tetanus, pertussis, pneumococcal infections and Haemophilus influenzae type b infection. This review analyses the advantages and limitations of maternal immunization as revealed by experience and the main publications.

Vaccines for the elderly

Vaccination is the most efficient strategy to prevent infectious disease. The increased vulnerability to infection of the elderly makes them a particularly important target population for vaccination. However, most vaccines are less immunogenic and efficient in the elderly because of age-related changes in the immune system. Vaccination against influenza, Streptococcus pneumoniae and varicella zoster virus is recommended for the elderly in many countries. Various strategies such as the use of adjuvants and novel administration routes are pursued to improve influenza vaccination for the elderly and recent developments in the field of pneumococcal vaccination led to the licensure of protein-conjugated polysaccharide vaccines containing up to 13 serotypes. As antibody titres are generally lower in the elderly and-particularly for inactivated vaccines-decline fast in the elderly, regular booster immunizations, for example against tetanus, diphtheria and, in endemic areas, tick-borne encephalitis, are essential during adulthood to ensure protection of the elderly. With increasing health and travel opportunities in old age the importance of travel vaccines for persons over the age of 60 is growing. However, little is known about immunogenicity and efficacy of travel vaccines in this age group. Despite major advances in the field of vaccinology over the last decades, there are still possibilities for improvement concerning vaccines for the elderly. Novel approaches, such as viral vectors for antigen delivery, DNA-based vaccines and innovative adjuvants, particularly toll-like receptor agonists, will help to achieve optimal protection against infectious diseases in old age.

Economic evaluations of childhood influenza vaccination: a critical review

The potential benefits of influenza vaccination programmes targeted at children have gained increasing attention in recent years. We conducted a literature search of economic evaluations of influenza vaccination in those aged ≤18 years. The search revealed 20 relevant articles, which were reviewed. The studies differed widely in terms of the costs and benefits that were included. The conclusions were generally favourable for vaccination, but often applied a wider perspective (i.e. including productivity losses) than the reference case for economic evaluations used in many countries. Several evaluations estimated outcomes from a single-year epidemiological study, which may limit their validity given the year-to-year variation in influenza transmissibility, virulence, vaccine match and prior immunity. Only one study used a dynamic transmission model able to fully incorporate the indirect herd protection to the wider community. The use of dynamic models offers great scope to capture the population-wide implications of seasonal vaccination efforts, particularly those targeted at children.

Personal decision-making criteria related to seasonal and pandemic A(H1N1) influenza-vaccination acceptance among French healthcare workers

BACKGROUND

Influenza-vaccination rates among healthcare workers (HCW) remain low worldwide, even during the 2009 A(H1N1) pandemic. In France, this vaccination is free but administered on a voluntary basis. We investigated the factors influencing HCW influenza vaccination.

METHODS

In June-July 2010, HCW from wards of five French hospitals completed a cross-sectional survey. A multifaceted campaign aimed at improving vaccination coverage in this hospital group was conducted before and during the 2009 pandemic. Using an anonymous self-administered questionnaire, we assessed the relationships between seasonal (SIV) and pandemic (PIV) influenza vaccinations, and sociodemographic and professional characteristics, previous and current vaccination statuses, and 33 statements investigating 10 sociocognitive domains. The sociocognitive domains describing HCWs' SIV and PIV profiles were analyzed using the classification-and-regression-tree method.

RESULTS

Of the HCWs responding to our survey, 1480 were paramedical and 401 were medical with 2009 vaccination rates of 30% and 58% for SIV and 21% and 71% for PIV, respectively (p<0.0001 for both SIV and PIV vaccinations). Older age, prior SIV, working in emergency departments or intensive care units, being a medical HCW and the hospital they worked in were associated with both vaccinations; while work shift was associated only with PIV. Sociocognitive domains associated with both vaccinations were self-perception of benefits and health motivation for all HCW. For medical HCW, being a role model was an additional domain associated with SIV and PIV.

CONCLUSIONS

Both vaccination rates remained low. Vaccination mainly depended on self-determined factors and for medical HCW, being a role model.

Under-explored assumptions in influenza vaccination models: implications for the universal vaccination of children

The aim of this study was to explore several important (but uncertain) assumptions in influenza models which affect the estimated benefits of vaccination programs. We combined consideration of these factors with the seasonal variability of influenza transmissibility to gain a better understanding of how they may influence influenza control efforts. As our case study, we considered the potential impact of universal seasonal childhood vaccination in Australia using a simplified age-stratified Susceptible Exposed Infectious Recovered (SEIR) model to simulate influenza epidemics and the impact of vaccination. We found that the choice of vaccine efficacy model was influential in determining the impact of vaccination. This choice interacted with other model assumption such as those around the infectiousness of asymptomatic cases and the match of the vaccine to the circulating strains. The methodological approach used to estimate influenza hospitalisations was also highly influential. Our study highlights the role that key modelling assumptions play when estimating the impact of vaccination against influenza.

An early (3-6 weeks) active surveillance study to assess the safety of pandemic influenza vaccine Focetria in a province of Emilia-Romagna region, Italy - part one

INTRODUCTION

An observational, non-comparative, prospective, surveillance study of individuals vaccinated with the MF59-adjuvanted A/H1N1 influenza vaccine, Focetria, (Novartis Vaccines & Diagnostics, Siena, Italy), was performed in Italy during the 2009 A/H1N1 influenza pandemic.

METHOD

This study assessed the short-term (six-week) safety profile of the investigational vaccine in real time. After vaccination (N=7943), adverse events (AE) were assessed using both active (telephone) and passive (healthcare database) follow-up in enrolled vaccinated subjects, including infants (6-23 months), pregnant women, and the immunosuppressed. The treating physicians of all subjects experiencing AEs post-vaccination were consulted for clinical information on the conditions reported. All AEs were coded according to ICD-10.

RESULTS

A total of 1583 AEs occurred during the study, 67 (4.2%) of which were serious adverse events (SAEs). One SAE was considered to be possibly related to vaccination (transitory and ill-defined neurologic disorder experienced by a 16-year-old asthmatic male). Three adverse events of special interest (AESI) were identified (convulsions experienced by two epileptic subjects), none of which were considered to be vaccine-related. Six individuals died during the study period, in each case the cause of death was not related to vaccination (four cases of severe underlying co-morbidity, one case of psychoactive drug misuse, and one case of acute myocardial infarction).

CONCLUSIONS

No cases of clinically relevant AEs, SAEs, or AESI were observed within a six-week period of vaccine administration. In accordance with existing clinical and post-marketing safety data, the results of this active surveillance study demonstrate a good safety profile for the MF59-adjuvanted A/H1N1 vaccine, Focetria, within the general population.

Development and testing of an instrument to assess nurses' knowledge, risk perception, health beliefs and behaviours related to influenza vaccination

AIMS AND OBJECTIVES

To develop an instrument to measure nurses' knowledge, risk perception and health beliefs towards influenza and influenza vaccination and their vaccination behaviours and evaluate its construct validity and internal consistency reliability.

BACKGROUND

Although instruments to assess predictors of nurses' vaccination behaviours have been developed, their validity and reliability have not been reported.

DESIGN

Instrument development and initial validity and reliability testing.

METHODS

The instrument was developed drawing on a literature review and expert consultation and was refined through pilot work. A cross-sectional survey using a revised version of the instrument was conducted among a convenience sample of 520 registered nurses (response rate 77.4%). Cronbach's alpha coefficient was calculated to determine internal consistency of the sub-scale in the instrument. Principal components analysis with varimax rotation was carried out to evaluate the instrument's construct validity and examine its internal structure.

RESULTS

Cronbach's alpha coefficients for the three newly developed scales ranged from 0.70-0.76. Principal components analysis produced a good fit and confirmed the internal design of the instrument. In the seasonal influenza knowledge sub-scale four factors explained 44.8% of the total variance; in the H1N1 knowledge sub-scale two factors explained 44.7% of the total variance. Three factors in the risk perception scale contributed 50.5% of the total variance and two factors in the vaccination behaviours scale contributed 62.1% of the total variance.

CONCLUSIONS

An instrument has been developed to assess nurses' knowledge, risk perception and health beliefs towards influenza and influenza vaccination and their vaccination behaviours. The instrument was valid and reliable for the setting where it was used.

RELEVANCE TO CLINICAL PRACTICE

This instrument could be used to assess nurses' knowledge, risk perception, health beliefs towards influenza and influenza vaccination and their vaccination behaviours. The three newly developed scales could also be used independently to measure variables influencing nurses' vaccination practices.

Prevalence of seasonal influenza vaccination and associated factors in people with chronic diseases in Hong Kong

Chronic disease patients are at high risk of developing serious influenza-related complications. This study investigated the prevalence of seasonal influenza vaccination (IV) and associated factors in such patients. A random sample of 704 Chinese adults with chronic disease was anonymously interviewed by telephone; 35·8% of them had ever taken up IV and 22·7% did so during the last flu season. The most frequently mentioned facilitator was recommendation made by a healthcare worker (HCW). Knowledge that IV is required annually, perceived severe health impacts of influenza, and recommendation made by a HCW were positively associated with previous IV and intention to take up IV in the next year, while perceived side-effects was inversely associated with previous IV and intention to take up IV. The coverage of IV in this study population was low. HCWs should clarify IV-related health beliefs in chronic disease patients and actively advise them to take up IV.

Benefits and effectiveness of administering pneumococcal polysaccharide vaccine with seasonal influenza vaccine: an approach for policymakers

For the influenza pandemic of 2009-2010, countries responded to the direct threat of influenza but may have missed opportunities and strategies to limit secondary pneumococcal infections. Delivering both vaccines together can potentially increase pneumococcal polysaccharide vaccine (PPV23) immunization rates and prevent additional hospitalizations and mortality in the elderly and other high-risk groups. We used PubMed to review the literature on the concomitant use of PPV23 with seasonal influenza vaccines. Eight of 9 clinical studies found that a concomitant program conferred clinical benefits. The 2 studies that compared the cost-effectiveness of different strategies found concomitant immunization to be more cost-effective than either vaccine given alone. Policymakers should consider a stepwise strategy to reduce the burden of secondary pneumococcal infections during seasonal and pandemic influenza outbreaks.

Pandemic influenza A/H1N1 vaccination coverage, adverse reactions, and reasons for vaccine refusal among medical students in Brazil

The aim of this cross-sectional study was to determine, among medical students at a public university in Rio de Janeiro, Brazil, the acceptance of the pandemic influenza A/H1N1 vaccine during the 2010 mass immunization campaign and the vaccine safety in this group and, among unvaccinated students, the reasons for refusing vaccination. Of a total of 858 students, 678 (79%) participated in the study. Vaccination coverage was 60.4% among students aged 20 to 39 years (an age group targeted for vaccination) and 43.8% among those who did not belong to this age group. The most frequent adverse reactions to the vaccine were pain at the injection site (8.7%) and fever (7.9%). There were no serious adverse reactions. Among students aged 20 to 39 years, the most common reasons for refusing the vaccine were "lack of time" (42.4%), "fear of adverse reactions" (41.9%), and "difficult access to the vaccine" (11.5%). Other reasons for vaccine refusal were "uncertainties about vaccine safety and efficacy" and "vaccination was not needed". To increase the acceptance of the influenza vaccine, a comprehensive immunization program should be offered to these students.

Differences in pandemic influenza vaccination policies for pregnant women in Europe

Background

An important component of the policy to deal with the H1N1 pandemic in 2009 was to develop and implement vaccination. Since pregnant women were found to be at particular risk of severe morbidity and mortality, the World Health Organization and the European Centers for Disease Control advised vaccinating pregnant women, regardless of trimester of pregnancy. This study reports a survey of vaccination policies for pregnant women in European countries.

Methods

Questionnaires were sent to European competent authorities of 27 countries via the European Medicines Agency and to leaders of registries of European Surveillance of Congenital Anomalies in 21 countries.

Results

Replies were received for 24 out of 32 European countries of which 20 had an official pandemic vaccination policy. These 20 countries all had a policy targeting pregnant women. For two of the four countries without official pandemic vaccination policies, some vaccination of pregnant women took place. In 12 out of 20 countries the policy was to vaccinate only second and third trimester pregnant women and in 8 out of 20 countries the policy was to vaccinate pregnant women regardless of trimester of pregnancy. Seven different vaccines were used for pregnant women, of which four contained adjuvants. Few countries had mechanisms to monitor the number of vaccinations given specifically to pregnant women over time. Vaccination uptake varied.

Conclusions

Differences in pandemic vaccination policy and practice might relate to variation in perception of vaccine efficacy and safety, operational issues related to vaccine manufacturing and procurement, and vaccination campaign systems. Increased monitoring of pandemic influenza vaccine coverage of pregnant women is recommended to enable evaluation of the vaccine safety in pregnancy and pandemic vaccination campaign effectiveness.

Incidence of influenza-like illness and severe acute respiratory infection during three influenza seasons in Bangladesh, 2008-2010

OBJECTIVE

To determine how much influenza contributes to severe acute respiratory illness (SARI), a leading cause of death in children, among people of all ages in Bangladesh.

METHODS

Physicians obtained nasal and throat swabs to test for influenza virus from patients who were hospitalized within 7 days of the onset of severe acute respiratory infection (SARI) or who consulted as outpatients for influenza-like illness (ILI). A community health care utilization survey was conducted to determine the proportion of hospital catchment area residents who sought care at study hospitals and calculate the incidence of influenza using this denominator.

FINDINGS

The estimated incidence of SARI associated with influenza in children < 5 years old was 6.7 (95% confidence interval, CI: 0-18.3); 4.4 (95% CI: 0-13.4) and 6.5 per 1000 person-years (95% CI: 0-8.3/1000) during the 2008, 2009 and 2010 influenza seasons, respectively. The incidence of SARI in people aged ≥ 5 years was 1.1 (95% CI: 0.4-2.0) and 1.3 (95% CI: 0.5-2.2) per 10,000 person-years during 2009 and 2010, respectively. The incidence of medically attended, laboratory-confirmed seasonal influenza in outpatients with ILI was 10 (95% CI: 8-14), 6.6 (95% CI: 5-9) and 17 per 100 person-years (95% CI: 13-22) during the 2008, 2009 and 2010 influenza seasons, respectively.

CONCLUSION

Influenza-like illness is a frequent cause of consultation in the outpatient setting in Bangladesh. Children aged less than  5 years are hospitalized for influenza in greater proportions than children in other age groups.

An analysis of national target groups for monovalent 2009 pandemic influenza vaccine and trivalent seasonal influenza vaccines in 2009-10 and 2010-11

BACKGROUND

Vaccination is generally considered to be the best primary prevention measure against influenza virus infection. Many countries encourage specific target groups of people to undertake vaccination, often with financial subsidies or a priority list. To understand differential patterns of national target groups for influenza vaccination before, during and after the 2009 influenza pandemic, we reviewed and analyzed the country-specific policies in the corresponding time periods.

METHODS

Information on prioritized groups targeted to receive seasonal and pandemic influenza vaccines was derived from a multi-step internet search of official health department websites, press releases, media sources and academic journal articles. We assessed the frequency and consistency of targeting 20 different groups within populations which are associated with age, underlying medical conditions, role or occupations among different countries and vaccines. Information on subsidies provided to specific target groups was also extracted.

RESULTS

We analyzed target groups for 33 (seasonal 2009 and 2009-10 vaccines), 72 (monovalent pandemic 2009-10 vaccine) and 34 (seasonal 2010 and 2010-11 vaccines) countries. In 2009-10, the elderly, those with chronic illness and health care workers were common targets for the seasonal vaccine. Comparatively, the elderly, care home residents and workers, animal contacts and close contacts were less frequently targeted to receive the pandemic vaccine. Pregnant women, obese persons, essential community workers and health care workers, however, were more commonly targeted. After the pandemic, pregnant women, obese persons, health care and care home workers, and close contacts were more commonly targeted to receive the seasonal vaccine compared to 2009-10, showing continued influence from the pandemic. Many of the countries provided free vaccines, partial subsidies, reimbursements or national health insurance coverage to specific target groups and over one-third of the countries offered universal subsidy regarding the pandemic vaccine. There was also some inconsistency between countries in target groups.

CONCLUSIONS

Differences in target groups between countries may reflect variable objectives as well as uncertainties regarding the transmission dynamics, severity and age-specific immunity against influenza viruses before and after vaccination. Clarification on these points is essential to elucidate optimal and object-oriented vaccination strategies.