High Risk For Influenza-related Complications Research Articles

Antivirals to prepare for surges in influenza cases: an economic evaluation of baloxavir marboxil for the Netherlands.

We perform a cost-effectiveness analysis (CEA) and budget impact analysis (BIA) of baloxavir marboxil compared to current care in the Netherlands for patients at risk of influenza-related complications, including patients with comorbidities and the elderly. In the CEA, a decision tree model was developed to assess the cost-effectiveness of baloxavir marboxil for a cohort of 52-year-olds from a societal perspective. A lifetime horizon was taken by incorporating the quality-adjusted life expectancy. The BIA included different epidemiological scenarios, estimating different plausible epidemiological scenarios for seasonal influenza considering the whole Dutch population with an increased risk of influenza complications. The base-case ICER was estimated to be €8,300 per QALY. At the willingness-to-pay threshold of €20,000 per QALY, the probability of being cost effective was 58%. The base-case expected budget impact was €5.7 million on average per year, ranging from €1.5 million to €10.5 million based on the severity of the influenza epidemic and vaccine effectiveness. In the Netherlands, baloxavir is a cost-effective treatment option for seasonal influenza, with a base-case ICER of €8,300 per QALY for the population aged 60years and over and patients at high risk of influenza-related complications. For a large part, this ICER is driven by the reduction of the illness duration of influenza and productivity gains in the working population.

Summary of the National Advisory Committee on Immunization (NACI) Statement-Recommendations on Fractional Influenza Vaccine Dosing in the Event of a Shortage: Pandemic preparedness.

At the commencement of a pandemic, it is important to consider the impact of respiratory infections on the health system and the possibility of vaccine shortages due to increased demand. In the event of an influenza vaccine shortage, a strategy for administration of fractional influenza vaccine doses might be considered. This article reviews the available evidence for efficacy, effectiveness, immunogenicity and safety of fractional influenza vaccine dosing, and summarizes the National Advisory Committee on Immunization (NACI) recommendations on fractional dosing strategies by public health programs in Canada. Two rapid literature reviews were undertaken to evaluate the efficacy, effectiveness, immunogenicity and safety of fractional influenza vaccine dosing via the intramuscular or intradermal route. The NACI evidence-based process was used to assess the quality of eligible studies, summarize and analyze the findings, and apply an ethics, equity, feasibility and acceptability lens to develop recommendations. There was limited evidence for the effectiveness of fractional influenza vaccine dosing. Fractional dosing studies were primarily conducted in healthy individuals, mainly young children and infants, with no underlying chronic conditions. There was fair evidence for immunogenicity and safety. Feasibility issues were identified with intradermal use in particular. NACI recommended that, in the event of a significant population-level shortage of influenza vaccine, a full-dose influenza vaccine should continue to be used, and existing vaccine supply should be prioritized for those considered to be at high risk or capable of transmitting to those at high risk of influenza-related complications or hospitalizations. NACI recommended against the use of fractional doses of influenza vaccine in any population.

Seasonal influenza vaccination of healthcare workers: a narrative review.

Influenza is an acute respiratory disease caused by the influenza virus which often occurs in outbreaks and epidemics worldwide. The World Health Organization recommends annual vaccination of healthcare workers (HCWs) against influenza, because most of them are involved in the direct care of patients with a high risk of influenza-related complications. Given the significance of the disease burden, a targeted literature review was conducted to assess issues related to influenza vaccination among HCWs. The primary aim of this review was to assess the incidence of influenza among medical personnel and healthcare-associated influenza, and to outline the benefits of influenza vaccination for patients and HCWs themselves. Vaccination of HCWs seems to be an important strategy for reducing the transmission of influenza from healthcare personnel to their patients and, therefore, for reducing patient morbidity and mortality, increasing patient safety, and reducing work absenteeism among HCWs. The benefits of influenza vaccination for their patients and for HCWs themselves are addressed in literature, but the evidence is mixed and often of low-quality. Int J Occup Med Environ Health. 2022;35(2):127-39.

971. Online Medical Education Improves Knowledge of Data on Appropriate and Timely Use of Influenza Antiviral Medications to Patients at High Risk for Influenza-Related Complications and Morbidity

Abstract Background Many patients are at a higher risk of influenza complications because of age and comorbidities. We sought to assess whether online education, focused on appropriate and timely use of influenza antiviral medications to patients at high risk for influenza-related complications and morbidity, could improve knowledge, competence, and confidence of clinicians. Methods Primary care physicians (PCPs) and pediatricians participated in a 30-minute video lecture with synchronized slides. Educational effect was assessed using a repeated-pairs design with pre-/post-assessment. Three multiple choice questions assessed knowledge/competence, and 1 question assessed confidence. Statistical tests to assess significance: Paired samples t-test for overall average number of correct responses and for confidence rating; McNemar’s test for individual questions (5% significance level, P < .05). Cohen’s d estimated the effect size impact on number of correct responses (< .20 modest, .20-.49 small, .59-.79 moderate, ≥.80 large). Data were collected from 10/28/20 to 12/23/20. Results Average knowledge/competence improved from 29% to 43% (N=430, P< .001, Cohen’s d = 0.46) among primary care physicians and from 31% to 43% (N=226, P< .001, Cohen’s d = 0.38) among pediatricians. Post participation, 12% more PCPs and pediatricians answered all questions correctly. Relative improvements post-participation in specific areas were as follows (P< .001): (i) 105% improvement among PCPs and 100% improvement among pediatricians in findings associated with the efficacy of treatment with antivirals for influenza in hospitalized patients. (ii) 117% improvement among PCPs and 104% improvement among pediatricians in identifying the antiviral with the greatest activity against influenza B viral strain as reported in a phase 3 clinical trial. (iii) 34% of PCPs and 46% of pediatricians had a measurable improvement in confidence after completing the program. Conclusion This study demonstrated the success of a video lecture with synchronized slides at improving PCPs and pediatricians knowledge, competence and confidence related to appropriate and timely use of influenza antiviral medications to patients at high risk for influenza-related complications and morbidity. Disclosures All Authors: No reported disclosures

Summary of the National Advisory Committee on Immunization (NACI) Seasonal Influenza Vaccine Statement for 2021-2022.

Several influenza vaccines are authorized in Canada and the evidence on influenza immunization is continually evolving. The National Advisory Committee on Immunization (NACI) provides recommendations regarding the use of seasonal influenza vaccines annually to the Public Health Agency of Canada (PHAC). To summarize NACI recommendations regarding the use of seasonal influenza vaccines for 2021-2022 and to highlight new recommendations. Annual influenza vaccine recommendations are developed by NACI's Influenza Working Group for consideration and approval by NACI. The development of the recommendations is based on the NACI evidence-based process. The following new recommendations were made: 1) Influvac® Tetra may be considered as an option among the standard dose quadrivalent inactivated influenza vaccines (IIV4-SD) offered to adults and children three years of age and older; 2) Fluzone High Dose Quadrivalent (IIV4-HD) may be considered an option for individuals 65 years of age and older who are currently recommended to receive Fluzone® High Dose (trivalent); and 3) Flucelvax® Quad may be considered amongst the quadrivalent influenza vaccines offered to adults and children nine years of age and older for annual influenza immunization. Guidance for use of influenza immunizations during the coronavirus disease 2019 pandemic is also highlighted. NACI continues to recommend that an age-appropriate influenza vaccine should be offered annually to anyone six months of age and older who does not have contraindications to the vaccine. Vaccination should be offered as a priority to people at high risk of influenza-related complications or hospitalization, people capable of transmitting influenza to those at high risk of complications, and others as indicated.

Cost-effectiveness of live-attenuated influenza vaccination among school-age children

The current pediatric vaccination program in England and Wales administers Live-Attenuated Influenza Vaccine (LAIV) to children ages 2–16 years old. Annual administration of LAIV to this age group is costly and poses substantial logistical issues. This study aims to evaluate the cost-effectiveness of prioritizing vaccination to age groups within the 2–16 year old age range to mitigate the operational and resource challenges of the current strategy. We performed economic evaluations comparing the influenza vaccination program from 1995–2013 to seven alternative strategies targeted at low risk individuals along the school age divisions Preschool (2–4 years old), Primary school (5–11 years old), and Secondary school (12–16 years old). These extensions are evaluated incrementally on the status quo scenario (vaccinating subgroups at high risk of influenza-related complications and individuals 65+ years old). Impact of vaccination was assessed using a transmission model from a previously published study and updated with new data. At all levels of coverage, all strategies had a 100% probability of being cost-effective at the current National Health Service threshold, £20,000/QALY gained. The incremental analysis demonstrated vaccinating Primary School children was the most cost-efficient strategy compared incrementally against others with an Incremental Cost-Effectiveness Ratio of £639 spent per QALY gained (Net Benefit: 404 M£ [155, 795]). When coverage was varied between 30%, 55%, and 70% strategies which included Primary school children had a higher probability of being cost-effective at lower willingness-to-pay levels. Although children were the vaccine target the majority of QALY gains occurred in the 25–44 years old and 65+ age groups. Influenza strain A/H3N2 incurred the greatest costs and QALYs lost regardless of which strategy was used. Improvement could be made to the current LAIV pediatric vaccination strategy by eliminating vaccination of 2–4 year olds and focusing on school-based delivery to Primary and Secondary school children in tandem.

A hidden vulnerable population: Young children up-to-date on vaccine series recommendations except influenza vaccines.

Very young children (under 2 years old) have high risk for influenza-related complications. Children 6 months or older in the US are recommended to receive influenza vaccination annually, yet uptake is substantially lower than other routinely-recommended vaccines. Existing nationally-representative studies on very young child influenza vaccine uptake has several limitations: few examine provider-verified influenza vaccination (relying on parental report), few contain parental vaccine attitudes variables (known to be crucial to vaccine uptake), and none to our knowledge consider intersectionality of social disadvantage nor how influenza vaccine determinants differ from those of other recommended vaccines. This nationally-representative study examines provider-verified data on 7,246 children aged 6-23 months from the most recent (2011) National Immunization Survey to include the restricted Parental Concerns module, focusing on children up-to-date on a series of vaccines (the 4:3:1:3:3:1:4 series) but not influenza vaccines ("hidden vulnerability to influenza"). About 71% of children were up-to-date on the series yet only 33% on influenza vaccine recommendations by their second birthday; 44% had hidden vulnerability to influenza. Independent of parental history of vaccine refusal and a myriad of health services use factors, no parental history of delaying vaccination was associated with 7.5% (2.6-12.5) higher probability of hidden vulnerability to influenza despite being associated with 15.5% (10.8-20.2) lower probability of being up-to-date on neither the series nor influenza vaccines. Thus, parental compliance with broad child vaccine recommendations and lack of vaccine hesitancy may not indicate choice to vaccinate children against influenza. Examination of intersectionality suggests that maternal college education may not confer improved vaccination among non-Hispanic Black and Hispanic children despite that it does for non-Hispanic White children. Policymakers and researchers from public health, sociology, and other sectors need to collaborate to further examine how vaccine hesitancy and intersectional social disadvantage interact to affect influenza vaccine uptake in young US children.

Influenza in patients with cancer after 2009 pandemic AH1N1: An 8-year follow-up study in Mexico.

BackgroundImmunosupressed patients are at high risk of influenza‐related complications. Influenza AH1N1 has been hypothesized to induce worse outcomes in patients with malignancies, but after the A(H1N1)pdm09 few publications have analyzed the presentation and complications related to influenza afterward.ObjectivesWe aimed to describe the characteristics, risk factors, and outcomes of influenza in an oncologic center after the 2009 pandemic and to compare our case distribution to the National community acquired influenza databases in Mexico and the United States.MethodsWe reviewed the cases of confirmed influenza in patients with cancer from an oncological center in Mexico from April 2009 to April 2017. Data on severity and influenza type, malignancy, comorbidities, and outcomes were recorded. We correlated data between the Centers for Disease Control and Prevention (CDC) in the United States and SISVEFLU (Influenza Surveillance Program) in Mexico.ResultsOne hundred eighty‐eight patients were included; 75 (39.9%) had a solid neoplasm and 113 (60.1%) had hematologic malignancies. AH1N1 was the most frequent influenza type (54.2%). Patients with hematologic malignancies had more pneumonia (55% vs 25%, P < .001), needed more hospitalizations (75% vs 39% P < .001), had higher all‐cause mortality at 30 days (20% vs 9% P = .048) and influenza‐associated mortality (17% vs 7% P = .041). Thirty (16%) patients died within 30 days, and 24 (12.7%) were related to influenza. Influenza type was not associated with worse outcomes. Yearly occurrence of influenza reported by the CDC and SISVEFLU showed a significant correlation (ρ = 0.823, P = .006).ConclusionsAH1N1 was the dominant serotype. Patients with hematologic malignancies had more severe influenza and presented worse outcomes. Annual SISVEFLU and CDC surveillance information showed a similar distribution of cases along time but influenza serotypes did not match for all seasons.

EXamining the knowledge, Attitudes and experiences of Canadian seniors Towards influenza (the EXACT survey)

BackgroundOlder adults are at high risk for influenza-related complications including worsening frailty and function. We surveyed older Canadians to explore the impact of influenza and determine how influenza knowledge influences vaccination decision-making.MethodsWe disseminated an online survey through a national polling panel. The survey included questions about the respondents’ influenza vaccination practices and knowledge about influenza. Using validated measures, they reported their frailty and functional status prior to the 2016/17 influenza season, during illness (if applicable), and following the season. Regression analyses were used to examine predictors of poor functional outcomes.ResultsFive thousand and fourteen adults aged 65 and older completed the survey; mean age was 71.3 ± 5.17 years, 42.6% had one or more chronic conditions, 7.8% were vulnerable and 1.8% were frail. 67.9% reported receiving last season’s influenza vaccine. Those who rarely/never receive the influenza vaccine were significantly less likely to correctly answer questions about influenza’s impact than those who receive the vaccine more consistently. Of the 1035 (21.5%) who reported experiencing influenza or influenza-like illness last season, 40% indicated a recovery longer than 2 weeks, and one-fifth had health and function declines during this time. Additionally, 3.1% of those afflicted “never fully recovered”. Older age, significant trouble with memory and having influenza/ILI were among the independent predictors of persistent declines in health and function.ConclusionsGiven that frailty and function are important considerations for older adults’ well-being and independence, healthcare decision-makers must understand the potential for significant temporary and long-term impacts of influenza to make informed vaccine-related policies and recommendations.

Summary of the NACI Seasonal Influenza Vaccine Statement for 2019-2020.

Many different influenza vaccines are authorized for use in Canada and new evidence on influenza and vaccines is continually emerging. The National Advisory Committee on Immunization (NACI) provides annual recommendations regarding the use of seasonal influenza vaccines to the Public Health Agency of Canada (PHAC) for the upcoming influenza season. To summarize NACI recommendations regarding the use of seasonal influenza vaccines for the 2019-2020 influenza season, including conclusions from reviews of evidence on 1) a new split virus quadrivalent inactivated influenza vaccine and 2) the comparative effectiveness and immunogenicity of subunit and split virus inactivated influenza vaccines in adults 65 years of age and older. For both topics, the NACI Influenza Working Group developed a predefined search strategy to identify all eligible studies, assessed their quality, summarized and analyzed the findings and, according to the NACI evidence-based process, proposed recommendations and identified the grade of evidence that supported them. In light of the evidence, the recommendations were then considered and approved by NACI. NACI concluded that the new split virus quadrivalent inactivated influenza vaccine has a safety and immunogenicity profile comparable to the quadrivalent inactivated influenza vaccines already authorized for adults and children 5 years of age and older (Grade B Evidence). Therefore, NACI recommended that this new vaccine may be considered among the quadrivalent inactivated influenza vaccines offered to adults and children five years of age and older (Discretionary NACI Recommendation). However, NACI concluded that the evidence is not sufficient (Grade I Evidence) to support specific recommendations on the differential use of subunit and split virus inactivated influenza vaccines in adults 65 years of age and older. NACI continues to recommend that an age-appropriate influenza vaccine should be offered annually to anyone six months of age and older who does not have contraindications to the vaccine, with focus on the groups for whom influenza vaccination is particularly recommended. This includes people at high risk of influenza-related complications or hospitalization, people capable of transmitting influenza to those at high risk, people who provide essential community services and people in direct contact with poultry infected with avian influenza during culling operations.

Evaluating the effectiveness of the influenza vaccine during respiratory outbreaks in Singapore’s long term care facilities, 2017

Influenza outbreaks occur periodically in Long Term Care Facilities (LTCFs) and vaccination is critical in preventing influenza infections. We evaluated the influenza vaccine effectiveness (VE) during respiratory outbreaks in LTCFs reported to the Ministry of Health, Singapore in 2017.A test-negative design was used to estimate the ratio of the odds of testing positive for influenza among vaccinated individuals to the odds among unvaccinated individuals. The VE was calculated as (1-odds ratio) × 100%. For adjusted VE, the estimates were derived using logistic regression adjusted for age group, gender, month of illness, and number of days from date of illness onset till to swab collection date. Estimates by influenza subtypes and post-vaccination time periods (15–180 days & 181–365 days) were also calculated using stratified data.264 individuals, with 118 laboratory-confirmed influenza cases [32 A(H1N1)pdm09, 75 A(H3N2), 11 A(untypable)], were included in the analysis. No one was identified to be infected with influenza B. The overall adjusted VE estimate was 40.5% (95% CI: −12.2–68.5%), while the subtype-specific adjusted VE estimates were −43.4% (95% CI: −312.4–50.2%) against A(H1N1)pdm09 and 57.1% (95% CI: 5.7–80.5%) against A(H3N2). At 15–180 days post-vaccination period, the adjusted VEs were 59.3% (95% CI: 18.0–79.8%) against all influenza, 35.4% (95% CI: −123.5–81.3%) against A(H1N1)pdm09 and 67.9% (95% CI: 22.5–86.7%) against A(H3N2). Estimates were not significant at 181–365 days post-vaccination.The influenza vaccine showed varying effectiveness among individuals in Singapore’s LTCFs in 2017, with a higher effectiveness among those who were more recently vaccinated. It remains an important tool in preventing influenza infections, especially for those who are at high risk of influenza-related complications.

Recommendations for Prevention and Control of Influenza in Children, 2018-2019.

The authors of this statement update the recommendations of the American Academy of Pediatrics for the routine use of influenza vaccine and antiviral medications in the prevention and treatment of influenza in children. Highlights for the upcoming 2018-2019 season include the following:1. Annual influenza immunization is recommended for everyone 6 months and older, including children and adolescents.2. The American Academy of Pediatrics recommends an inactivated influenza vaccine (IIV), trivalent or quadrivalent, as the primary choice for influenza vaccination in children because the effectiveness of a live attenuated influenza vaccine against influenza A(H1N1) was inferior during past influenza seasons and is unknown for this upcoming season.3. A live attenuated influenza vaccine may be used for children who would not otherwise receive an influenza vaccine (eg, refusal of an IIV) and for whom it is appropriate because of age (2 years of age and older) and health status (ie, healthy and without any underlying chronic medical condition).4. All 2018-2019 seasonal influenza vaccines contain an influenza A(H1N1) vaccine strain similar to that included in the 2017-2018 seasonal vaccines. In contrast, the influenza A(H3N2) and influenza B (Victoria lineage) vaccine strains included in the 2018-2019 trivalent and quadrivalent vaccines differ from those in the 2017-2018 seasonal vaccines.a. Trivalent vaccines contain an influenza A(Michigan/45/2015[H1N1])pdm09-like virus, an influenza A(Singapore/INFIMH-16-0019/2016[H3N2])-like virus (updated), and an influenza B (Colorado/60/2017)-like virus (B/Victoria lineage; updated).b. Quadrivalent vaccines contain an additional B virus (Phuket/3073/2013-like virus; B/Yamagata lineage).5. All children with egg allergy of any severity can receive an influenza vaccine without any additional precautions beyond those recommended for all vaccines.6. Pregnant women may receive an influenza vaccine (IIV only) at any time during pregnancy to protect themselves as well as their infants, who benefit from the transplacental transfer of antibodies. Postpartum women who did not receive vaccination during pregnancy should be encouraged to receive an influenza vaccine before discharge from the hospital. Influenza vaccination during breastfeeding is safe for mothers and their infants.7. The vaccination of health care workers is a crucial step in preventing influenza and reducing health care-associated influenza infections because health care personnel often care for individuals at high risk for influenza-related complications.8. Pediatricians should attempt to promptly identify their patients who are suspected of having an influenza infection for timely initiation of antiviral treatment when indicated and on the basis of shared decision-making between each pediatrician and child caregiver to reduce morbidity and mortality. Although best results are seen when a child is treated within 48 hours of symptom onset, antiviral therapy should still be considered beyond 48 hours of symptom onset in children with severe disease or those at high risk of complications (see Table 2 in the full policy statement).

Antiviral treatment for outpatient use during an influenza pandemic: a decision tree model of outcomes averted and cost-effectiveness.

BackgroundMany countries have acquired antiviral stockpiles for pandemic influenza mitigation and a significant part of the stockpile may be focussed towards community-based treatment.MethodsWe developed a spreadsheet-based, decision tree model to assess outcomes averted and cost-effectiveness of antiviral treatment for outpatient use from the perspective of the healthcare payer in the UK. We defined five pandemic scenarios—one based on the 2009 A(H1N1) pandemic and four hypothetical scenarios varying in measures of transmissibility and severity.ResultsCommunity-based antiviral treatment was estimated to avert 14–23% of hospitalizations in an overall population of 62.28 million. Higher proportions of averted outcomes were seen in patients with high-risk conditions, when compared to non-high-risk patients. We found that antiviral treatment was cost-saving across pandemic scenarios for high-risk population groups, and cost-saving for the overall population in higher severity influenza pandemics. Antiviral effectiveness had the greatest influence on both the number of hospitalizations averted and on cost-effectiveness.ConclusionsThis analysis shows that across pandemic scenarios, antiviral treatment can be cost-saving for population groups at high risk of influenza-related complications.

Summary of the NACI Seasonal Influenza Vaccine Statement for 2018-2019.

There are many different influenza vaccines authorized for use in Canada and new evidence on influenza and vaccines is emerging all the time. The National Advisory Committee on Immunization (NACI) provides recommendations annually regarding seasonal influenza vaccines to the Public Health Agency of Canada (PHAC). To summarize the NACI recommendations regarding the use of seasonal influenza vaccines for the 2018-2019 influenza season in light of two NACI reviews conducted on 1) the risk of serious influenza-related complications in children and adults with neurologic and neurodevelopment conditions and 2) the efficacy/effectiveness of high-dose and adjuvanted inactivated influenza vaccines in persons 65 years of age and older. For both topics, NACI's Influenza Working Group developed a predefined search strategy to identify all eligible studies, assessed their quality, summarized and analyzed the findings, proposed recommendations and identified the Grade of evidence that supported them. In light of the evidence, the recommendations were then considered and approved by NACI. NACI concludes there is fair evidence to recommend that children and adults with neurologic and neurodevelopment conditions are groups for whom influenza immunization is particularly recommended (Evidence Grade B recommendation). On choosing influenza vaccines for persons 65 years of age and older, at a programmatic level, NACI recommends that any of the four influenza vaccines available for use should be used. There is insufficient evidence to make a comparative recommendation on the use of these vaccines at a programmatic level (Grade I). At an individual level, NACI recommends that high-dose trivalent inactivated influenza vaccine (TIV) should be offered over standard-dose TIV to persons 65 years of age and older (Grade A). There is insufficient evidence to make comparative recommendations on the use of MF59-adjuvanted TIV and quadrivalent inactivated influenza vaccine over standard-dose TIV (Grade I). NACI continues to recommend annual influenza vaccination for all individuals aged six months and older, with particular focus on people at high risk of influenza-related complications or hospitalization, people capable of transmitting influenza to those at high risk, people who provide essential community services and people in direct contact during culling operations with poultry infected with avian influenza.

Recommendations for Prevention and Control of Influenza in Children, 2017 - 2018.

This statement updates the recommendations for routine use of the seasonal influenza vaccine and antiviral medications for the prevention and treatment of influenza in children. The American Academy of Pediatrics recommends annual seasonal influenza immunization for everyone 6 months and older, including children and adolescents. Highlights for the upcoming 2017-2018 season include the following:1. Annual universal influenza immunization is indicated with either a trivalent or quadrivalent (no preference) inactivated vaccine;2. The 2017-2018 influenza A (H1N1) vaccine strain differs from that contained in the 2016-2017 seasonal vaccines. The 2017-2018 influenza A (H3N2) vaccine strain and influenza B vaccine strains included in the trivalent and quadrivalent vaccines are the same as those contained in the 2016-2017 seasonal vaccines: a. trivalent vaccine contains an A/Michigan/45/2015 (H1N1)pdm09-like virus, an A/Hong Kong/4801/2014 (H3N2)-like virus, and a B/Brisbane/60/2008-like virus (B/Victoria lineage); and b. quadrivalent vaccine contains an additional B virus (B/Phuket/3073/2013-like virus [B/Yamagata lineage]);3. Quadrivalent live attenuated influenza vaccine (LAIV4) is not recommended for use in any setting in the United States during the 2017-2018 influenza season. This interim recommendation, originally made in 2016, followed observational data from the US Influenza Vaccine Effectiveness Network revealing that LAIV4 performed poorly against influenza A (H1N1)pdm09 viruses in recent influenza seasons;4. All children with an egg allergy of any severity can receive an influenza vaccine without any additional precautions beyond those recommended for any vaccine;5. All health care personnel should receive an annual seasonal influenza vaccine, a crucial step in preventing influenza and reducing health care-associated influenza infections, because health care personnel often care for individuals at high risk for influenza-related complications; and6. Pediatricians should attempt to promptly identify children suspected of having influenza infection for timely initiation of antiviral treatment, when indicated, to reduce morbidity and mortality. Best results are seen when treated within 48 hours of symptom onset.

Summary of the NACI Statement on Seasonal Influenza Vaccine for 2017-2018.

Influenza is a respiratory infection caused primarily by influenza A and B viruses. Vaccination is the most effective way to prevent influenza and its complications. The National Advisory Committee on Immunization (NACI) provides recommendations regarding seasonal influenza vaccines annually to the Public Health Agency of Canada (PHAC). To summarize the NACI recommendations regarding the use of seasonal influenza vaccines for the 2017-2018 influenza season. Annual influenza vaccine recommendations are developed by NACI's Influenza Working Group for consideration and approval by NACI, based on NACI's evidence-based process for developing recommendations. The recommendations include a consideration of the burden of influenza illness and the target populations for vaccination; efficacy and effectiveness, immunogenicity and safety of influenza vaccines; vaccine schedules; and other aspects of influenza immunization. These recommendations are published annually on the Agency's website in the NACI Advisory Committee Statement: Canadian Immunization Guide Chapter on Influenza and Statement on Seasonal Influenza Vaccine (the Statement). The annual statement has been updated for the 2017-2018 influenza season to incorporate recommendations for the use of live attenuated influenza vaccine (LAIV) that were contained in two addenda published after the 2016-2017 statement. These recommendations were 1) that egg-allergic individuals may be vaccinated against influenza using the low ovalbumin-containing LAIV licensed for use in Canada and 2) to continue to recommend the use of LAIV in children and adolescents 2-17 years of age, but to remove the preferential recommendation for its use. NACI continues to recommend annual influenza vaccination for all individuals aged six months and older, with particular focus on people at high risk of influenza-related complications or hospitalization, people capable of transmitting influenza to those at high risk, and others as indicated.

Impact of Clinical Pathway and Rapid Direct Influenza Polymerase Chain Reaction Test Introduction on Readmissions Among Non-hospitalized Children with Influenza-Like Illness

BackgroundDiagnosing influenza is challenging in children as influenza-like illness (ILI) symptoms are nonspecific. A clinical pathway was introduced in the emergency department (ED) of a large pediatric hospital to screen and treat patients at high risk of influenza-related complications. A new highly accurate, rapid polymerase chain reaction (PCR) influenza test was introduced the next year to provide more timely results. We aimed to measure the impact of the pathway and new PCR test on rates of all-cause ED readmissions and subsequent hospital admissions in all children with ILI discharged from the ED.MethodsWe conducted a retrospective cohort study of non-hospitalized children≤18 years presenting to the ED with ILI over 3 winter seasons. ILI cases were identified using syndromic surveillance definitions. Outcomes included any return ED encounter or hospital admission within 2 weeks of initial ED visit. We compared difference in outcomes between the years before pathway introduction, after pathway introduction, and after rapid PCR test introduction. Multivariate logistic regression adjusted for pertinent sociodemographic and clinical covariates.ResultsAmong 10799 children with ILI, 6.1% had an ED readmission and 2.5% had a hospital admission within 2 weeks of an initial ED visit. Overall rates of ED readmission or hospitalization did not differ significantly by study year (5.7% vs 6.5% vs 6.1%, P = 0.41, and 2.9% vs 2.4% vs 2.3%, P = 0.36). In multivariate analysis, pathway introduction alone was not associated with likelihood of ED readmission or hospitalizations. However, rapid PCR test introduction with the pathway was associated with lower odds of hospitalization (aOR 0.70, 95% CI 0.51–0.97). High-risk status was associated with higher odds of ED readmission (aOR 1.42, 95% CI 1.21–1.68). High-risk status and severity of illness at the initial ED visit were associated with higher odds of hospitalization (aOR 1.51, 95% CI 1.13–2.03; aOR 10.66, 95% CI 6.05–18.79).ConclusionClinical pathway and rapid PCR test introduction does not decrease all-cause ED readmissions but does decrease all-cause hospital admissions in children with ILI. Clinical factors such as severity of illness and high-risk status play a large role in determining outcomes.Disclosures All authors: No reported disclosures.

Influenza vaccination: a one-shot deal to reduce cardiovascular events.

This editorial refers to ‘Influenza vaccination and risk of hospitalization in patients with heart failure: a self-controlled case series study’, by H. Mohseni et al. doi: 10.1093/eurheartj/ehw411. Influenza contributes to significant morbidity and mortality across the globe every year. The estimated number of hospitalizations attributable to influenza infection are grossly underestimated among patients with cardiovascular (CV) disease, in whom a severe upper respiratory infection can initiate a cascade of physiological events that ultimately lead to acute worsening or exacerbation of underlying heart disease. Patients with heart failure in particular are at a high risk for influenza-related complications,1 including hospitalizations, which occur more frequently during the winter months, often in conjunction with influenza infection.2 A number of mechanisms support a causal association between influenza infection and CV events ( Figure 1 ). Influenza infection can result in increased metabolic demand, adrenergic surge, endothelial dysfunction, hypercoagulability, and hypoxia.3 Systemic immune stimulation and inflammation in the setting of influenza infection can trigger acute plaque rupture. Influenza predisposes patients to develop other infections such as pneumonia, which may itself be associated with increased CV risk due to prolonged elevation in cytokine levels and a procoagulant state.4–6 Moreover, influenza is known to cause myocardial depression directly,7 possibly mediated through increases in proinflammatory cytokines,8,9 and histological evidence of myocardial injury, myocarditis, and myocyte necrosis has been demonstrated from patients following influenza-related deaths.10 Figure 1 Influenza infection increases the risk for acute cardiovascular events (myocardial infarction and heart failure exacerbations) through several mechanisms involving pro-inflammatory mediators, neurohormonal activation, and activation of the coagulation cascade. Influenza vaccination has been accepted as an effective, well-established strategy to reduce influenza-related illness, and this potential benefit in high-risk …

Recommendations for Prevention and Control of Influenza in Children, 2016-2017.

The purpose of this statement is to update recommendations for the routine use of seasonal influenza vaccine and antiviral medications for the prevention and treatment of influenza in children. The AAP recommends annual seasonal influenza immunization for everyone 6 months and older, including children and adolescents. Highlights for the upcoming 2016-2017 season include the following: 1. Annual universal influenza immunization is indicated with either a trivalent or quadrivalent (no preference) inactivated vaccine.2. The 2016-2017 influenza A (H3N2) vaccine strain differs from that contained in the 2015-2016 seasonal vaccines. The 2016-2017 influenza B vaccine strain (Victoria lineage) included in the trivalent vaccine differs from that contained in the 2015-2016 seasonal trivalent vaccines (Yamagata lineage). a. Trivalent vaccine contains an A/California/7/2009 (H1N1)pdm09-like virus, an A/Hong Kong/4801/2014 (H3N2)-like virus, and a B/Brisbane/60/2008-like virus (B/Victoria lineage). b. Quadrivalent vaccine contains an additional B virus (B/Phuket/3073/2013-like virus [B/Yamagata lineage]).3. Quadrivalent live attenuated influenza vaccine (LAIV4) should not be used in any setting during the 2016-2017 influenza season in light of the evidence for poor effectiveness of LAIV4 in recent seasons, particularly against influenza A (H1N1)pdm09 viruses.4. All children with egg allergy can receive influenza vaccine with no additional precautions from those of routine vaccinations.5. All HCP should receive an annual influenza vaccine, a crucial step in preventing influenza and reducing health care-associated influenza infections. Because HCP may care for or live with people at high risk of influenza-related complications, it is especially important for them to get vaccinated annually.6. Pediatricians should attempt to promptly identify children suspected of having influenza for rapid antiviral treatment, when indicated, to reduce morbidity and mortality.

Summary of the National Advisory Committee on Immunization (NACI) Statement on Seasonal Influenza Vaccine for 2016-2017.

Influenza is a respiratory infection caused primarily by influenza A and B viruses. Vaccination is the most effective way to prevent influenza and its complications. The National Advisory Committee on Immunization (NACI) provides recommendations regarding seasonal influenza vaccines annually to the Public Health Agency of Canada (the Agency). To summarize the NACI recommendations regarding the use of seasonal influenza vaccines for the 2016-2017 influenza season. Annual influenza vaccine recommendations are developed by NACI's Influenza Working Group for consideration and approval by NACI, based on NACI's evidence-based process for developing recommendations, and include a consideration of the burden of influenza illness and the target populations for vaccination; efficacy and effectiveness, immunogenicity and safety of influenza vaccines; vaccine schedules; and other aspects of influenza immunization. These recommendations are published annually on the Agency's website in the NACI Advisory Committee Statement: Canadian Immunization Guide Chapter on Influenza and Statement on Seasonal Influenza Vaccine (the Statement). The annual NACI seasonal influenza vaccine recommendations have been updated for the 2016-2017 influenza season to include adults with neurologic or neurodevelopment conditions among the groups for whom influenza vaccination is particularly recommended; to include the new high-dose, trivalent inactivated influenza vaccine for use in adults 65 years of age and over; to recommend that egg-allergic individuals may also be vaccinated against influenza using the low ovalbumin-containing live attenuated influenza vaccine (LAIV) licensed for use in Canada (NACI has previously recommended that egg-allergic individuals may be vaccinated using inactivated influenza vaccines); and to remove the preferential recommendation for the use of LAIV in children 2-17 years of age. Two addenda to the 2016-2017 Statement address these new LAIV recommendations. NACI continues to recommend annual influenza vaccination for all individuals aged six months and older, with particular focus on people at high risk of influenza-related complications or hospitalization, people capable of transmitting influenza to those at high risk and others as indicated.