Experts' opinion for improving global adolescent vaccination rates: a call to action.

Worldwide, lifestyle and resource disparities among adolescents contribute to unmet health needs, which have crucial present and future public health implications for both adolescents and broader communities. Risk of infection among adolescents is amplified by biological, behavioral, and environmental factors; however, infectious diseases to which adolescents are susceptible are often preventable with vaccines. Beyond these concerns, there is a lack of knowledge regarding adolescent vaccination and disease risk among parents and adolescents, which can contribute to low vaccine uptake. Promising efforts have been made to improve adolescent vaccination by programs with motivational drivers and comprehensive communication with the public. In May 2017, a multidisciplinary group of experts met in Amsterdam, Netherlands, to discuss adolescent vaccine uptake, as part of an educational initiative called the Advancing Adolescent Health Spring Forum. This article presents consensus opinions resulting from the meeting, which pertain to the burden of vaccine-preventable diseases among adolescents, reasons for low vaccine uptake, and common characteristics of successful strategies for improving adolescent vaccination.Conclusion: There is an urgent "call to action," particularly targeting healthcare providers and public health authorities, for the prioritization of adolescent vaccination as a necessary element of preventive healthcare in this age group.What is Known:• Despite increased risk of certain infectious diseases, adolescent vaccination uptake remains low.What is New:• Barriers to adolescent vaccine uptake include lack of information regarding vaccines and disease risk, health system inadequacies, and insufficient healthcare follow-up.• Successful efforts to improve adolescent vaccine uptake need cohesive leadership and involvement of multiple stakeholders, as well as youth-friendly messaging; healthcare providers and policymakers should prioritize adolescent vaccination and implement proven program strategies to improve adolescent health worldwide.

[After-effects of invasive meningococcal diseases]. / Impact des répercussions des infections invasives à méningocoques.

AFTER-EFFECTS OF INVASIVE MENINGOCOCCAL DISEASES. Invasive meningococcal infections (IMI) still have a mortality rate of 11% in France. Recent nationwide studies have been able to quantify the long-term sequelae among survivors and highlight their diversity. In addition to the immediate effects seen at the end of hospitalization, numerous sequelae can emerge months or even years later. It is currently estimated that 20 to 30 % of survivors will experience at least one sequela, with 9 to 10 % having multiple after-effects. The most common sequelae are neurological (such as epilepsy and severe motor disorders) and psychological (like anxiety). Physical after-effects, such as skin scarring or amputations, while less frequent, often entail significant treatment cost. Cognitive difficulties, academic-learning challenges, and psychological, behavioral, or emotional disorders, are frequently diagnosed late and are probably underestimated. Communication or language problems carry a risk ratio > 20 compared to controls. This wide range of sequelae contributes to the complexity and high cost of care. It shows the importance of obtaining the most accurate possible estimate of IMI's impact and their after-effects, as well as implementing the preventive measures now available.

IMPACT DES RÉPERCUSSIONS DES INFECTIONS INVASIVES À MÉNINGOCOQUE. Les infections invasives à méningocoques (IIM) affichent encore un taux de mortalité de 11 % en France. Des études récentes, à l'échelle de chaque pays, ont permis de mieux quantifier les séquelles chez les survivants et en préciser la diversité. Au-delà des conséquences immédiates observées à la sortie de l'hôpital, de nombreuses séquelles peuvent apparaître de manière différée, survenant parfois plusieurs mois, voire des années après l'infection. On estime actuellement que 20 à 30 % des survivants présenteront au moins une séquelle, et 9 à 10 % en cumuleront plusieurs. Les plus fréquentes sont de nature neurologique (comme l'épilepsie ou des troubles moteurs sévères) ou psychologique (notamment l'anxiété). Les séquelles physiques, comme des cicatrices cutanées, voire des amputations, bien que moins fréquentes, ont une prise en charge coûteuse. Les difficultés cognitives, les troubles d'apprentissage ainsi que des problèmes comportementaux ou émotionnels, dont le diag nostic est souvent tardif, sont vraisemblablement sous-estimés. Les troubles de communication ou de langage ont un risk ratio supérieur à 20 par rapport aux témoins. Cette diver sité des séquelles contribue à la complexité et au coût de leur prise en charge. Cela souligne l'importance d'une estimation aussi précise que possible de l'impact des IIM et de leurs séquelles, ainsi que de la mise en oeuvre des mesures de prévention actuellement disponibles.

Invasive meningococcal disease in older adults: current perspectives and call for action.

PURPOSE: Invasive meningococcal disease (IMD) is a devastating condition. While most attention is directed towards disease in children and adolescents, IMD poses an important cause of morbidity and mortality in adults ≥60 years. While immunization is a critical component of healthy ageing strategies, meningococcal immunization is not routinely offered to older adults. The aim of this review was to summarize clinical and epidemiological aspects of IMD and available immunization strategies, with a particular focus on disease in older individuals, to emphasize the importance of this rather neglected area. METHODS: An expert working group was established to evaluate clinical and epidemiological data to raise awareness of IMD in older individuals, and develop suggestions to improve the existing burden. RESULTS: Routine child and adolescent meningococcal immunization has substantially reduced IMD in these targeted populations. Consequently, prevalence and proportion of IMD among those ≥60 years, mostly unvaccinated, is increasing in developed countries (accounting for up to 25% of cases). IMD-related mortality is highest in this age-group, with substantial sequelae in survivors. IMD due to serogroups W and Y is more prevalent among older adults, often with atypical clinical features (pneumonia, gastrointestinal presentations) which may delay timely treatment. CONCLUSIONS: IMD in older adults remains overlooked and greater awareness is required at clinical and societal levels. We encourage clinicians and immunization policy makers to reconsider IMD, with a call for action to remedy existing inequity in older adult access to protective meningococcal immunization.

Public health management of pertussis in adults: Practical challenges and future strategies.

A panel of 24 international experts met in July 2022 to discuss challenges associated with pertussis detection, monitoring, and vaccination in adults; conclusions from this meeting are presented. There has been a shift in the epidemiology of pertussis toward older children and adults. This shift has been attributed to the waning of infection- or vaccine-induced immunity, newer detection techniques causing detection bias, and possibly the replacement of whole-cell pertussis with acellular vaccines in high-income countries, which may lead to immunity waning more quickly. The burden of adult pertussis is still likely under-ascertained due to widespread under-recognition by healthcare professionals (HCPs), under-diagnosis, and under-reporting in this age group. Non-standardized testing guidance and varied case definitions have contributed to under-reporting. Key barriers to HCP engagement with the tetanus, diphtheria, and pertussis (Tdap) vaccine include low awareness, lack of time/funding, and lack of motivation due to low prioritization of Tdap.

Understanding the impact of adult pertussis and current approaches to vaccination: A narrative review and expert panel recommendations.

Pertussis has several notable consequences, causing economic burden, increased strain on healthcare facilities, and reductions in quality of life. Recent years have seen a trend toward an increase in pertussis cases affecting older children and adults. To boost immunity, and protect vulnerable populations, an enduring approach to vaccination has been proposed, but gaps remain in the evidence surrounding adult vaccination that are needed to inform such a policy. Gaps include: the true incidence of pertussis and its complications in adults; regional variations in disease recognition and reporting; and incidence of severe disease, hospitalizations, and deaths in older adults. Better data on the efficacy/effectiveness of pertussis vaccination in adults, duration of protection, and factors leading to poor vaccine uptake are needed. Addressing the critical evidence gaps will help highlight important areas of unmet need and justify the importance of adult pertussis vaccination to healthcare professionals, policymakers, and payers.

Preventing Respiratory Syncytial Virus in Children in France: A Narrative Review of the Importance of a Reinforced Partnership Between Parents, Healthcare Professionals, and Public Health Authorities.

The highly contagious respiratory syncytial virus (RSV) is responsible for up to approximately 50,000 hospitalisations during each RSV season in children aged under 5 years in France, with the burden greatest in infants younger than 1 year who were born at term. There is a need for a strategy to universally protect young children from RSV infection, and thereby reduce the pressure that RSV places every year on RSV-infected children, their parents, and French healthcare systems. Potential strategies currently undergoing clinical investigation include passive immunisation via maternal vaccination or administration of long-acting monoclonal antibodies at or soon after birth, followed by vaccination later in infancy or childhood. An ongoing partnership and collaboration between parents, public health authorities, and frontline primary healthcare will need to be reinforced once these new RSV prevention strategies are available, to facilitate their use and ensure that all children receive adequate protection from the start of their first RSV season.

Immunization technologies: Time to consider new preventative solutions for respiratory syncytial virus infections.

New technologies for the prevention of infectious diseases are emerging to address unmet medical needs, in particular, the use of long-acting monoclonal antibodies (mAb) to prevent Respiratory Syncytial Virus (RSV) lower respiratory tract disease in infants during their first RSV season. The lack of precedent for mAbs for broad population protection creates challenges in the assessment of upcoming prophylactic long-acting mAbs for RSV, with associated consequences in legislative and registration categorization, as well as in recommendation, funding, and implementation pathways. We suggest that the legislative and regulatory categorization of preventative solutions should be decided by the effect of the product in terms of its impact on the population and health-care systems rather than by the technology used or its mechanism of action. Immunization can be passive and active, both having the same objective of prevention of infectious diseases. Long-acting prophylactic mAbs work as passive immunization, as such, their recommendations for use should fall under the remit of National Immunization Technical Advisory Groups or other relevant recommending bodies for inclusion into National Immunization Programs. Current regulations, policy, and legislative frameworks need to evolve to embrace such innovative preventative technologies and acknowledge them as one of key immunization and public health tools.

Prevention of pneumococcal diseases in the post-seven valent vaccine era: a European perspective.

BACKGROUND: The burden of invasive pneumococcal disease in young children decreased dramatically following introduction of the 7-valent pneumococcal conjugate vaccine (PCV7). The epidemiology of S. pneumoniae now reflects infections caused by serotypes not included in PCV7. Recently introduced higher valency pneumococcal vaccines target the residual burden of invasive and non-invasive infections, including those caused by serotypes not included in PCV7. This review is based on presentations made at the European Society of Pediatric Infectious Diseases in June 2011. DISCUSSION: Surveillance data show increased circulation of the non-PCV7 vaccine serotypes 1, 3, 6A, 6C, 7 F and 19A in countries with routine vaccination. Preliminary evidence suggests that broadened serotype coverage offered by higher valency vaccines may be having an effect on invasive disease caused by some of those serotypes, including 19A, 7 F and 6C. Aetiology of community acquired pneumonia remains a difficult clinical diagnosis. However, recent reports indicate that pneumococcal vaccination has reduced hospitalisations of children for vaccine serotype pneumonia. Variations in serotype circulation and occurrence of complicated and non-complicated pneumonia caused by non-PCV7 serotypes highlight the potential of higher valency vaccines to decrease the remaining burden. PCVs reduce nasopharyngeal carriage and acute otitis media (AOM) caused by vaccine serotypes. Recent investigations of the interaction between S. pneumoniae and non-typeable H. influenzae suggest that considerable reduction in severe, complicated AOM infections may be achieved by prevention of early pneumococcal carriage and AOM infections. Extension of the vaccine serotype spectrum beyond PCV7 may provide additional benefit in preventing the evolution of AOM. The direct and indirect costs associated with pneumococcal disease are high, thus herd protection and infections caused by non-vaccine serotypes both have strong effects on the cost effectiveness of pneumococcal vaccination. Recent evaluations highlight the public health significance of indirect benefits, prevention of pneumonia and AOM and coverage of non-PCV7 serotypes by higher valency vaccines. SUMMARY: Routine vaccination has greatly reduced the burden of pneumococcal diseases in children. The pneumococcal serotypes present in the 7-valent vaccine have greatly diminished among disease isolates. The prevalence of some non-vaccine serotypes (e.g. 1, 7 F and 19A) has increased. Pneumococcal vaccines with broadened serotype coverage are likely to continue decreasing the burden of invasive disease, and community acquired pneumonia in children. Further reductions in pneumococcal carriage and increased prevention of early AOM infections may prevent the evolution of severe, complicated AOM. Evaluation of the public health benefits of pneumococcal conjugate vaccines should include consideration of non-invasive pneumococcal infections, indirect effects of vaccination and broadened serotype coverage.

[Epidemiology and the burden of RSV]. / Épidémiologie et fardeau du VRS.

RSV is an almost obligatory virus responsible for upper (rhinitis and otitis) and lower (bronchiolitis and asthma attack) respiratory infections in children under 5 years of age. Reinfections are frequent at all ages because immunity is only partial and does not last long. Young children under the age of 1 are the most affected. The majority of these children are healthy. Having a risk factor (premature birth, heart disease, bronchopulmonary dysplasia, but also passive smoking) increases the severity of RSV pathology. Very few children currently benefit from prevention by anti-RSV monoclonal antibodies. The annual cost of care, the various socio-economic costs are a public health reality in three care sectors: out-patient, pediatric emergencies, hospitalization. Subsequent consequences: repeated wheezing and asthma, should also be taken into consideration and integrated into public health decisions. Progress in recognizing this pathology is desirable: distribution of diagnostic tests in the city; providing parents with information.

Le VRS est un virus quasi obligatoire responsable d'infections respiratoires hautes (rhinite et otite) et basses (bronchiolite et crise d'asthme) chez l'enfant de moins de 5 ans. Les réinfections sont fréquentes du fait d'une immunité partielle, peu durable, à tous les âges de la vie. Les jeunes enfants de moins de 1 an sont les plus touchés. La majorité de ces enfants sont bien portants. Avoir un facteur de risque (prématurité, cardiopathie, dysplasie bronchopulmonaire mais aussi tabagisme passif) majore la sévérité de la pathologie à VRS. Très peu d'enfants bénéficient actuellement d'une prévention par les anticorps monoclonaux anti-VRS. La charge annuelle en soins, les coûts socioéconomiques variés constituent une réalité de santé publique portant sur les trois secteurs de soins : ambulatoire, urgences pédiatriques, hospitalisation.Les conséquences ultérieures : répétition de wheezing, asthme, devraient aussi être pris en considération et intégrés dans les décisions de santé publique.Des progrès dans la reconnaissance de cette pathologie sont souhaitables : diffusion des tests diagnostiques en ville ; information aux parents.

Preventing invasive meningococcal disease in early infancy.

This review considers the pathogenesis, diagnosis, and epidemiology of invasive meningococcal disease in infants, to examine and critique meningococcal disease prevention in this population through vaccination. High rates of meningococcal disease and poor outcomes, particularly for very young infants, highlight the importance of meningococcal vaccination in early infancy. Although effective and safe meningococcal vaccines are available for use from 6 weeks of age, they are not recommended globally. Emerging real-world data from the increased incorporation of these vaccines within immunization programs inform recommendations regarding effectiveness, appropriate vaccination schedule, possible long-term safety effects, and persistence of antibody responses. Importantly, to protect infants from IMD, national vaccination recommendations should be consistent with available data regarding vaccine safety, effectiveness, and disease risk.

Care pathways in invasive meningococcal disease: a retrospective analysis of the French national public health insurance database.

Invasive meningococcal disease (IMD) carries a high burden in terms of mortality, long-term complications, and cost, which can be significantly reduced by vaccination. The objectives of this case-control study were to document the care pathways of patients with IMD before, during, and after hospitalization and to assess in-hospital complications and long-term sequelae. Cases consisted of all people hospitalized for IMD in France between 2012 and 2017. Controls were matched by age, gender, and district of residence. Data were extracted from the French national public health insurance database on demographics, hospitalizations, mortality and potential sequelae of IMD. Overall, 3,532 cases and 10,590 controls were assessed and followed up for 2.8 years (median). During hospitalization, 1,577 cases (44.6%) stayed in an intensive care unit, 1,238 (35.1%) required mechanical ventilation, and 43 (1.2%) underwent amputation; 293 cases (8.3%) died in hospital and a further 163 (4.6%) died following discharge; 823 cases (25.4% of survivors) presented ≥1 sequela and 298 (9.2%) presented multiple sequelae. The most frequently documented sequelae were epilepsy (N = 205; 5.8%), anxiety (N = 196; 5.5%), and severe neurological disorders (N = 193; 5.5%). All individual sequelae were significantly more frequent (p < .0001) in cases than controls. Hearing/visual impairment and communication problems were conditions that presented the highest risk for cases compared to controls (risk ratios >20 in all cases). In conclusion, this study highlights the importance of providing optimal medical care for patients with IMD, of minimizing the delay before hospitalization, and of effective prevention through comprehensive vaccination programs.

Benefits of providing optimal medical care for IMD patients.Importance of minimising the delay before hospitalization.IMD remains challenging to diagnose, and vaccination is the most efficient way to prevent the disease and its complications.

Healthcare Resource Consumption and Cost of Invasive Meningococcal Disease in France: A Study of the National Health Insurance Database.

INTRODUCTION: Invasive meningococcal disease (IMD) is an uncommon but serious infectious disease. Its economic burden is known to be high but is poorly characterised. The objective of this study was to determine costs, as captured in the healthcare claims database, incurred by all patients hospitalised for IMD in France over a 6-year period. METHODS: This case-control study was performed using the French national public health insurance database (SNDS). Cases comprised all individuals hospitalised with acute IMD in France between 2012 and 2017 inclusive. For each case, three controls were identified, matched for age, gender and region of residence. All healthcare resource consumption by cases and controls during the follow-up period was documented. Costs were analysed for the index hospitalisation in cases, 1 year following the index date and then for 5 years following the index date. Costs were assigned from national tariffs. The analysis was performed from a societal perspective. IMD sequelae were identified from hospital discharge summaries. RESULTS: A total of 3532 cases and 10,590 controls were evaluated. The mean per capita cost of the index IMD hospitalisation was €11,256, and increased with age and with the presence of sequelae. In the year following the index date, mean per capita direct medical costs were €6564 in cases and €2890 in controls. Annual costs were €4254 in cases without sequelae, €10,799 in cases with one sequela and €20,096 in cases with more than one sequela. In the fifth year of follow-up, mean per capita costs were €2646 in cases and €1478 in controls. The excess cost in cases was principally due to the management of sequelae. Amputation, skin scarring and mental retardation generated per capita costs in excess of €20,000 in the first year and in excess of €10,000 for subsequent years. CONCLUSION: The economic burden of IMD in France is high and, over the long-term, is driven by sequelae management.

Risk factors for invasive meningococcal disease: a retrospective analysis of the French national public health insurance database.

Vaccination of at-risk populations against Neisseria meningitidis is an important strategy to prevent invasive meningococcal disease (IMD). The objective of this study was to characterize preexisting risk factors in patients with IMD and to compare their relative importance. This case-control analysis was performed in the French national public health insurance database (SNDS). Cases consisted of all people hospitalized for IMD in France over a six-year period (2012-2017). Controls were matched by age, gender, and district of residence. Medical risk factors were identified from ICD-10 codes in the SNDS. Socioeconomic risk factors studied were low household income and social deprivation of the municipality of residence. Associations of these risk factors with hospitalization for IMD were quantified as odds ratios (ORs) between cases and controls with their 95% confidence intervals (95%CI). The medical risk factors showing the most robust associations were congenital immunodeficiency (OR: 39.1 [95%CI: 5.1-299], acquired immunodeficiency (10.3 [4.5-24.0]) and asplenia/hyposplenia (6.7 [3.7-14.7]). In addition, certain chronic medical conditions, such as autoimmune disorders (5.4 [2.5-11.8]), hemophilia (4.7 [1.8-12.2]) and severe chronic respiratory disorders (4.3 [3.1-6.2]) were also strongly associated, as was low household income (1.68 [1.49-1.80]). In conclusion, this study has documented potential risk factors associated with hospitalization for IMD in a large and comprehensive sample of individuals with IMD in France. Several of the risk factors identified may help identify groups who could benefit from targeted prevention measures (such as vaccination) in order to reduce the burden of IMD.

[First season of pandemic influenza A/H1N1]. / Evaluation de la première vague epidémique liée a la grippe A(H1N1).

Influenza virus A/H1N1 2009 is a specific combination of internal genes explaining its pandemic character. Compared with seasonal influenza, influenza like illnesses were more frequent in young healthy people (children and adults). In France, among 1 329 severe cases, 20% had no risk factors and 312 subjects (23.5%) died. Compared with young adults without RF, the risk of severe case was 10-fold in pregnant women or 5-fold in infants (< 1 yr). A risk factor (in similar age group/without risk factor) multiplied the risk by 20 to 30 between 2 and 64 yrs, by 18 after 64 yrs, by 130 in infants < 1 yr, by over 300 between 1 and 2 yrs, and by 20 in pregnant women. A/H1N1 vaccination, proposed to the French population, was organized by the State in dedicated vaccination centers, in a staggered approach relying on pre-established priority groups, the sequential arrival of vaccines, the type of available vaccines, most often in multidoses. The official recommendations were adapted over time (age group, number of doses, type of vaccine utilized). Pandemrix and Focetria were the most casual; from mid-November 2009, Panenza was available. There was a 3 weeks interval between seasonal vaccination and pandemic one. Global coverage rate achieved is 8%. No peculiar severe adverse events and no signal of Guillain Barré syndrome were notified to the national pharmacovigilance net.

Varicella vaccination in Europe - taking the practical approach.

Varicella is a common viral disease affecting almost the entire birth cohort. Although usually self-limiting, some cases of varicella can be serious, with 2 to 6% of cases attending a general practice resulting in complications. The hospitalisation rate for varicella in Europe ranges from 1.3 to 4.5 per 100,000 population/year and up to 10.1% of hospitalised patients report permanent or possible permanent sequelae (for example, scarring or ataxia). However, in many countries the epidemiology of varicella remains largely unknown or incomplete. In countries where routine childhood vaccination against varicella has been implemented, it has had a positive effect on disease prevention and control. Furthermore, mathematical models indicate that this intervention strategy may provide economic benefits for the individual and society. Despite this evidence and recommendations for varicella vaccination by official bodies such as the World Health Organization, and scientific experts in the field, the majority of European countries (with the exception of Germany and Greece) have delayed decisions on implementation of routine childhood varicella vaccination, choosing instead to vaccinate high-risk groups or not to vaccinate at all. In this paper, members of the Working Against Varicella in Europe group consider the practicalities of introducing routine childhood varicella vaccination in Europe, discussing the benefits and challenges of different vaccination options (vaccination vs. no vaccination, routine vaccination of infants vs. vaccination of susceptible adolescents or adults, two doses vs. one dose of varicella vaccine, monovalent varicella vaccines vs. tetravalent measles, mumps, rubella and varicella vaccines, as well as the optimal interval between two doses of measles, mumps, rubella and varicella vaccines). Assessment of the epidemiology of varicella in Europe and evidence for the effectiveness of varicella vaccination provides support for routine childhood programmes in Europe. Although European countries are faced with challenges or uncertainties that may have delayed implementation of a childhood vaccination programme, many of these concerns remain hypothetical and with new opportunities offered by combined measles, mumps, rubella and varicella vaccines, reassessment may be timely.

Pertussis Prevention: Reasons for Resurgence, and Differences in the Current Acellular Pertussis Vaccines.

Pertussis is an acute respiratory disease caused by Bordetella pertussis. Due to its frequency and severity, prevention of pertussis has been considered an important public health issue for many years. The development of the whole-cell pertussis vaccine (wPV) and its introduction into the pediatric immunization schedule was associated with a marked reduction in pertussis cases in the vaccinated cohort. However, due to the frequency of local and systemic adverse events after immunization with wPV, work on a less reactive vaccine was undertaken based on isolated B. pertussis components that induced protective immune responses with fewer local and systemic reactions. These component vaccines were termed acellular vaccines and contained one or more pertussis antigens, including pertussis toxin (PT), filamentous haemagglutinin (FHA), pertactin (PRN), and fimbrial proteins 2 (FIM2) and 3 (FIM3). Preparations containing up to five components were developed, and several efficacy trials clearly demonstrated that the aPVs were able to confer comparable short-term protection than the most effective wPVs with fewer local and systemic reactions. There has been a resurgence of pertussis observed in recent years. This paper reports the results of a Consensus Conference organized by the World Association for Infectious Disease and Immunological Disorders (WAidid) on June 22, 2018, in Perugia, Italy, with the goal of evaluating the most important reasons for the pertussis resurgence and the role of different aPVs in this resurgence.

Varicella vaccination in Europe: are we ready for a universal childhood programme?

Safe and effective vaccines against varicella zoster virus (VZV), the aetiological agent of varicella and shingles, have been available in Europe for the last 5-10 years. The USA has had a universal childhood vaccination policy since 1995 and this has resulted in a dramatic decrease in the incidence, morbidity and mortality related to varicella. The economic and medical burden of VZV has led to discussions regarding both the desirability and feasibility of a similar routine immunisation policy for all European children. This article examines the epidemiology of varicella in Europe and how the data emerging from the USA can be used to achieve adequate prevention of the disease. It looks into the current evidence of the health economic evaluation of universal varicella vaccination and explores the concerns surrounding such a policy, including the postulated impact on the incidence of zoster. In conclusion, the Society of Independent European Vaccination Experts (SIEVE) recommends that the immunisation of susceptible adolescents needs to be urgently implemented, in addition to the current recommendations targeting high-risk patients, their close contacts with a negative history of varicella and seronegative health-care workers. A universal policy, optimally incorporating a two-dose schedule, will be needed to finally reduce the burden of disease of varicella from a societal point of view. The SIEVE recommends the implementation of such a policy as soon as financially and practically possible.

[Seasonal influenza in children]. / Grippe saisonnière de l'enfant.

Influenza in children is now recognized as a yearly burden, with severe symptoms or complications responsible for hospitalizations in young children and at risk groups. Clinical diagnosis, similar to adults in children over 4-5 years of age, is much less feasible in young infants due to overlap of symptoms with other respiratory or digestive viral epidemics. Rapid diagnostic tests could thus be useful. Prevention relies on vaccination but recommendations are restricted (at risk groups, professional and familial surroundings), vaccine schedule is a constraint, and the vaccine protective efficacy is increasing with the children age. Thus, specific anti-virals could be useful as curative treatment or even prophylaxis.

[Quadrivalent influenza vaccine: What is changed and what are the benefits?] / Vaccin grippal quadrivalent : quels changements pour quels bénéfices ?

Currently, circulating viruses responsible for annual seasonal influenza epidemics belong to two influenza A subtypes, A(H1N1) and A(H3N2), and to two antigenically distinct type B lineages, B/Yamagata and B/Victoria lineages. Like diseases due to influenza A virus, influenza B virus diseases may have severe consequences and should be prevented. Until now, in France, the vaccines used to prevent seasonal influenza were trivalent, systematically targeting viruses belonging to both A subtypes and to one or other of the B lineages. The protective efficacy of trivalent vaccines is diminished during the seasons when viruses belonging to both B lineages cocirculated or when the circulating dominant type B virus belonged to a lineage different from that targeted by the vaccine strain. By targeting viruses belonging to both B lineages, quadrivalent vaccines improve the antigenic concordance between circulating and vaccine type B strains. Three inactivated quadrivalent vaccines are authorized for marketing in France and should be available for the 2018-2019 season. It is expected that, by providing enlarged protection, these quadrivalent influenza vaccines will improve vaccine efficacy, the confidence in immunization of the public, the satisfaction of health professionals, and ultimately will help to complete immunization coverage.