High Risk For Influenza Complications Research Articles

Use of influenza antiviral agents by ambulatory care clinicians during the 2012-2013 influenza season.

Early antiviral treatment (≤2 days since illness onset) of influenza reduces the probability of influenza-associated complications. Early empiric antiviral treatment is recommended for those with suspected influenza at higher risk for influenza complications regardless of their illness severity. We describe antiviral receipt among outpatients with acute respiratory illness (ARI) and antibiotic receipt among patients with influenza. We analyzed data from 5 sites in the US Influenza Vaccine Effectiveness Network Study during the 2012-2013 influenza season. Subjects were outpatients aged ≥6 months with ARI defined by cough of ≤7 days' duration; all were tested for influenza by polymerase chain reaction (PCR). Medical history and prescription information were collected by medical and pharmacy records. Four sites collected prescribing data on 3 common antibiotics (amoxicillin-clavulanate, amoxicillin, and azithromycin). Of 6766 enrolled ARI patients, 509 (7.5%) received an antiviral prescription. Overall, 2366 (35%) had PCR-confirmed influenza; 355 (15%) of those received an antiviral prescription. Among 1021 ARI patients at high risk for influenza complications (eg, aged <2 years or ≥65 years or with ≥1 chronic medical condition) presenting to care ≤2 days from symptom onset, 195 (19%) were prescribed an antiviral medication. Among participants with PCR-confirmed influenza and antibiotic data, 540 of 1825 (30%) were prescribed 1 of 3 antibiotics; 297 of 1825 (16%) were prescribed antiviral medications. Antiviral treatment was prescribed infrequently among outpatients with influenza for whom therapy would be most beneficial; in contrast, antibiotic prescribing was more frequent. Continued efforts to educate clinicians on appropriate antibiotic and antiviral use are essential to improve healthcare quality.

Evaluating the Feasibility and Participants’ Representativeness of an Online Nationwide Surveillance System for Influenza in France

The increasing Internet coverage and the widespread use of digital devices offer the possibility to develop new digital surveillance systems potentially capable to provide important aid to epidemiological and public health monitoring and research. In France, a new nationwide surveillance system for influenza-like illness, GrippeNet.fr, was introduced since the 2011/2012 season based on an online participatory mechanism and open to the general population. We evaluate the recruitment and participation of users to the first pilot season with respect to similar efforts in Europe to assess the feasibility of establishing a participative network of surveillance in France. We further investigate the representativeness of the GrippeNet.fr population along a set of indicators on geographical, demographic, socio-economic and health aspects. Participation was widespread in the country and with rates comparable to other European countries with partnered projects running since a longer time. It was not representative of the general population in terms of age and gender, however all age classes were represented, including the older classes (65+ years old), generally less familiar with the digital world, but considered at high risk for influenza complications. Once adjusted on demographic indicators, the GrippeNet.fr population is found to be more frequently employed, with a higher education level and vaccination rate with respect to the general population. A similar propensity to commute for work to different regions was observed, and no significant difference was found for asthma and diabetes. Results show the feasibility of the system, provide indications to inform adjusted epidemic analyses, and highlight the presence of specific population groups that need to be addressed by targeted communication strategies to achieve a higher representativeness in the following seasons.

Trends in Influenza Vaccine Coverage in Pregnant Women, 2008 to 2012

Pregnant women are at increased risk of severe influenza-related complications and hospitalizations and are a priority group for influenza vaccination. To examine coverage of seasonal and pandemic influenza A (H1N1) vaccines in pregnant women in a managed care setting, from 2008 to 2012. Retrospective cohort study of 10,145 pregnant women. H1N1 and seasonal influenza vaccination rates. Seasonal influenza vaccine coverage increased from 38% to 63% between the 2008-2009 and 2010-2011 seasons, and then dropped to 61% in 2011-2012. Vaccine coverage was higher in women considered at high risk of influenza complications, increasing from 43% in 2008-2009 to 71% in 2010-2011, before decreasing to 69% in 2011-2012. H1N1 vaccine coverage was greater than seasonal influenza coverage in 2009-2010 in the overall pregnant population (61% vs 53%) and in the high-risk group (64% vs 59%). We observed statistically significant differences in vaccination rates by trimester, gravidity, maternal age, and race/ethnicity. Vaccination rates increased significantly from 2008 to 2011, then dropped slightly in 2011-2012. Continued efforts are needed to ensure adequate vaccination coverage in this high-risk population.

Impact of medical and behavioural factors on influenza-like illness, healthcare-seeking, and antiviral treatment during the 2009 H1N1 pandemic: USA, 2009-2010.

We analysed a cross-sectional telephone survey of U.S. adults to assess the impact of selected characteristics on healthcare-seeking behaviours and treatment practices of people with influenza-like illness (ILI) from September 2009 to March 2010. Of 216,431 respondents, 8.1% reported ILI. After adjusting for selected characteristics, respondents aged 18-64 years with the following factors were more likely to report ILI: a diagnosis of asthma [adjusted odds ratio (aOR) 1.88, 95% CI 1.67-2.13] or heart disease (aOR 1.41, 95% CI 1.17-1.70), being disabled (aOR 1.75, 95% CI 1.57-1.96), and reporting financial barriers to healthcare access (aOR 1.63, 95% CI 1.45-1.82). Similar associations were seen in respondents aged ≥ 65 years. Forty percent of respondents with ILI sought healthcare, and 14% who sought healthcare reported receiving influenza antiviral treatment. Treatment was not more frequent in patients with high-risk conditions, except those aged 18-64 years with heart disease (aOR 1.90, 95% CI 1.03-3.51). Of patients at high risk for influenza complications, self-reported ILI was greater but receipt of antiviral treatment was not, despite guidelines recommending their use in this population.

Improving Influenza Vaccination Rates— A Straightforward Task or a Multifaceted Challenge?

Annual vaccination with trivalent inactivated vaccines has been proven as safe and efficacious in preventing influenza and its complications. It is recommended especially to the elderly (>65) and other people at high risk for influenza complications and death such as patients with chronic medical conditions. Healthcare workers, who are considered to transmit infection to patients, or reciprocally, can be infected during encounters with patients, are also strongly advised to regularly receive vaccines. In order to improve influenza vaccination rates in countries in Europe, health authorities set targets for vaccination coverage by 2010. Despite the substantial efforts done, coverage rates maintain low. It is considered that informed decisions, based on existing evidence, are likely to cope with improving vaccination rates. Intention of this manuscript is to address some important issues connected with influenza vaccination which, to be able to aid the evidence, need to be further clearified. To support the debate, the author presented some dubious facts from the own practice experiences. As a long-lasting solution to improve vaccination practice strategies, strengthening programed vaccination is suggested. This concept would include implementation of nationwide vaccination protocols and their harmonization by the common logistics, and standardized data collection based on installation of E-health records. This strategy would allow data comparison among different populations. As based on this debate, improving influenza vaccination rates is not likely to be easy to perform straightforward task, but a multifaceted, long term challenge.

Influenza A (H3N2) Variant Virus-Related Hospitalizations—Ohio, 2012

Since July 2012, 305 cases of infection with influenza A (H3N2) variant (H3N2v) virus containing the influenza A (H1N1)pdm09 M gene have occurred in multiple U.S. states, primarily associated with swine exposure at agricultural fairs. In Ohio, from July 28 to September 25, 2012, a total of 106 confirmed H3N2v cases were identified through enhanced surveillance. Whereas most H3N2v patients experienced mild, self-limited influenza-like illness (ILI), 11 of the Ohio patients were hospitalized, representing 69% of all H3N2v hospitalizations in the United States. Of these hospitalized H3N2v patients, six were at increased risk for influenza complications because of age or underlying medical conditions, including the only H3N2v-associated fatality reported in the United States to date. This report summarizes the epidemiology and clinical features of the 11 hospitalized H3N2v patients in Ohio. These findings reinforce the recommendation for persons at high risk for influenza complications to avoid swine exposure at agricultural fairs this fall. In addition, persons not at high risk for influenza complications who wish to reduce their risk for infection with influenza viruses circulating among pigs also should avoid swine and swine barns at agricultural fairs this fall.

Evolution of the Pediatric Influenza Vaccination Program in the United States

* Abbreviations: ACIP — : Advisory Committee on Immunization Practices CDC — : Centers for Disease Control and Prevention SLV — : school-located mass vaccination TIV — : trivalent influenza vaccine For many years, the Advisory Committee on Immunization Practices (ACIP) for the Centers for Disease Control and Prevention (CDC) focused its vaccination policy on persons at higher risk for influenza complications (eg, older adults, children and adults with certain high-risk conditions, pregnant women) and their contacts (eg, household contacts, health care personnel). Unfortunately, although vaccination coverage rates varied, they remained low for most adult and pediatric high-risk groups, other than persons aged ≥65 years.1 In conjunction with the recognition that influenza vaccination recommendations for high-risk target populations were not being optimally implemented, the adverse effects of influenza illness on all children was increasingly recognized. This led to the expansion of vaccination recommendations for children, beginning in 2002, when influenza vaccination was “encouraged” for children aged 6 through 23 months, and in 2004, when a full recommendation was issued for this age group.2,3 That recommendation was based largely on studies documenting that these young children had influenza-related hospitalization rates that were comparable to hospitalization rates in older persons with underlying risk conditions who were targeted to receive influenza vaccine.4–6 Full recommendation was added for other groups who are at risk, such as adults and children with neuromuscular and other conditions that can compromise respiratory function or the handling of respiratory secretions, as data became available.7 The gradual, incremental, group-by-group expansion of influenza recommendations to additional age and risk groups was challenging for providers and the public. In the ensuing years, immunization experts, professional organizations, and other stakeholders debated the advantages and challenges of expanding routine influenza vaccination to all persons in the United States.8–10 At a meeting of immunization and … Address correspondence to Richard Schieber, MD, MPH, Epidemiology and Analysis Program Office, Office of Surveillance, Epidemiology, and Laboratory Services, Centers for Disease Control and Prevention, 1600 Clifton Rd NE, MS E33, Atlanta, GA 30333. E-mail: rschieber{at}cdc.gov

Implementing an Influenza Vaccination Programme for Adults Aged ≥65 Years in Poland

Influenza is a common respiratory disease occurring in seasonal patterns, and may lead to severe complications in frail populations such as the elderly. In Poland, influenza vaccination is recommended for people aged ≥65 years; however the vaccine coverage rate in the elderly is very low. The fact that influenza vaccine is neither reimbursed by the National Health Insurance (Narodowy Fundusz Zdrowia [NFZ]) nor financed via a National Immunization Program (NIP) could be a reason for the low coverage rate. This study assessed the cost effectiveness of the full reimbursement of an influenza vaccination programme in Poland for people aged ≥65 years. A decision-analytic model was developed to compare costs and outcomes associated with the current situation in which influenza vaccination is not reimbursed and a new situation in which it would be fully covered by the NFZ. The model was parameterized to Poland using data from the literature and from the Central Statistic Office of Poland. Within the elderly population, 50% were considered to be at high risk of influenza complications. An influenza attack rate of 3.5% was used for calculation purposes. Influenza-associated hospitalizations and death rates were estimated at 439.9 per 100 000 person-years and 79.1 per 100 000 person-years, respectively. Cost estimates were derived from a cost study conducted in Poland. Costs are presented in Polish Zloty (PLN) [2009 mean exchange rate: 1 PLN = €0.232]. Only direct medical costs were included to fit to the NFZ perspective. To reflect the seasonality of influenza, a time horizon of 1 year was chosen. Life-years and quality-adjusted life-years (QALYs) accumulated over future years were discounted at a rate of 5% as recommended by Polish guidelines. Deterministic and probabilistic sensitivity analyses were conducted. In Poland, the introduction of the public funding of influenza vaccination for people aged ≥65 years would cost PLN 79 million when an increase in coverage rate from 13.5% to 40% is assumed. 23 900 cases of influenza, 1777 hospitalizations and 548 premature deaths would be averted each year due to the influenza vaccination programme. Fifty-seven persons would need to be vaccinated to prevent one case of influenza. To prevent one hospitalization and one death due to influenza, 842 and 2809 individuals would need to be vaccinated, respectively. The new strategy would be very cost effective compared with the current situation with an incremental cost-effectiveness ratio (ICER) of PLN26 118/QALY, which is below the 2009 yearly gross domestic product (GDP) per capita. Deterministic sensitivity analyses demonstrated that the most influential variables for the ICER were vaccine efficacy against death, excess hospitalization rate, utility norms, influenza attack rate, vaccine efficacy against hospitalization, and discount rates. All ICERs computed were below the threshold of 3 GDP per capita. From the probabilistic analysis, the proposed new influenza vaccination programme, if implemented, was predicted to be cost effective from the NFZ perspective with a probability of 100%, given the same threshold. Implementing a vaccination programme in Poland in which influenza vaccination would be fully reimbursed by the NFZ for people aged ≥65 years would be a very cost-effective strategy.

Antiviral Treatment of Influenza in Children

Influenza causes substantial morbidity in children in the United States each year. The 2009 influenza A (H1N1) pandemic disproportionately affected the pediatric population and resulted in a substantially increased number of hospitalizations and deaths among children. Early influenza antiviral treatment reduces the duration of illness, frequency of complications, antibiotic use, and health care utilization costs attributable to influenza. A comprehensive strategy to reduce influenza-associated hospitalizations and deaths among children should include empiric antiviral treatment for suspected or confirmed influenza of any severity in children who are hospitalized; who have severe, complicated, or progressive illness; or who are at high risk for influenza complications. Here, we summarize data on the burden of influenza among children in the United States, the indications for influenza antiviral treatment among children, the available evidence for influenza antiviral treatment, and antiviral treatment considerations, including resistance and adverse events.

Pharmacoeconomic evaluation of the MF59--adjuvanted influenza vaccine in the elderly population in Italy.

Influenza vaccination has proven effective in the reduction of influenza-like illness (ILI) cases and influenza-related hospitalizations, drug consumption, primary care consultations and deaths in the elderly population. The aim of this study is the assessment of the financial budget impact of a seasonal vaccination program based on the use of the MF59 adjuvanted vaccine as compared with the traditional vaccine or the absence of vaccination in Italian elderly population. A pharmacoeconomic simulation model was developed to simulate the effect of the three different vaccination programs during a single influenza season. Health economics and demographic data were taken from specific Italian sources, and vaccine effectiveness data derived from published literature. Direct medical costs were considered according to current Italian prices and tariffs. About 83% of the 12 million people of at least 65 years of age currently resident in Italy can be considered at high risk for influenza complications due to underlying chronic diseases. Absence of vaccination could lead to more than 2 million ILl cases, and 29,000 related deaths. The vaccination program with a coverage rate of 65.6% would lead to an estimated 1.5 million ILl cases (26.9% reduction) with a standard vaccine and to 1.3 million (35.8% reduction) with the MF59 adjuvanted vaccine with a relative increase of avoided cases of 33,1%. The standard vaccination program produced a moderate direct cost increase of about 50 million Euro (+4.6%), whereas the adjuvanted vaccine provided an estimated saving of about 74 million Euro (-6.8%), both compared to the non vaccination. Cost savings were mainly related to hospital admissions avoided in the elderly population (>or=65 years of age). The vaccination with the MF59 adjuvanted vaccine resulted more effective and cost saving when compared with the standard vaccination and with no vaccination, thus representing the optimal strategy for the elderly population. The standard vaccine, even though a light cost increase, still proved to be effective compared to the null option, with the initial cost for the vaccination program nearly offset by healthcare resources savings obtained during the season.

Immunization 2011: Expanding Coverage, Enhancing Protection

Annually, the ACIP of the Centers for Disease Control and Prevention issues a revised Adult Immunization Schedule that is approved by the major specialty societies representing physicians who care ...

Protecting Young Infants by Maternal Influenza Vaccination

Although infants are at high risk for influenza complications, they are ineligible for influenza vaccination until age 6 months. Vaccination of

Prevalence of high-risk indications for influenza vaccine varies by age, race, and income

Estimates of the proportions of the population who are at high risk of influenza complications because of prior health status or who are likely to have decreased vaccination response because of immunocompromising conditions would enhance public health planning and model-based projections. We estimate these proportions and how they vary by population subgroups using national data systems for 2006–2008. The proportion of individuals at increased risk of influenza complications because of health conditions varied 10-fold by age (4.2% of children <2 years to 47% of individuals >64 years). Age-specific prevalence differed substantially by gender, by racial/ethnic groups (with African Americans highest in all age groups) and by income. Individuals living in families with less than 200% of federal poverty level (FPL) were significantly more likely to have at least one of these health conditions, compared to individuals with 400% FPL or more (3-fold greater among <2 and 30% greater among >64 years). Among children, there were significantly elevated proportions in all regions compared to the West. The estimated prevalence of immunocompromising conditions ranged from 0.02% in young children to 6.14% older adults. However, national data on race/ethnicity and income are not available for most immunocompromising conditions, nor is it possible to fully identify the degree of overlap between persons with high-risk health conditions and with immunocompromising conditions. Modifications to current national data collection systems would enhance the value of these data for public health programs and influenza modeling.

Influenza Vaccination Rates of Children in Households with High-Risk Adults

Household contacts of people at high risk for influenza complications should receive yearly influenza vaccination to reduce potential viral transmission. We evaluated influenza vaccine coverage among children to determine whether or not living with a high-risk adult predicts the likelihood of being vaccinated. Using the 2006 National Health Interview Survey, we examined influenza vaccination rates among children (aged 1-17 years) who did and did not reside in a household with an adult at high risk for influenza-related complications. Among 24,195 sampled families, there were 8,976 high-risk adults, 18.9% of whom reported living with a person 17 years of age of younger. Influenza vaccination rates by age group among children living with high-risk adults were 41.7% (1 year), 30.3% (2-4 years), and 20.0% (5-17 years). Unadjusted influenza vaccination rates were significantly higher for school-aged children who lived with a high-risk adult compared with those who did not (20.0% vs. 15.0%, p < 0.001). Among children younger than 5 years of age, for whom vaccination was universally recommended at the time of the survey, the rates did not differ. After adjusting for the child's age, gender, race, insurance coverage, medical visits, and chronic conditions, children who lived with a high-risk adult were not statistically more likely than those who did not live with a high-risk adult to receive influenza vaccination (odds ratio = 1.16, 95% confidence interval 0.99, 1.36). Children had low rates of influenza vaccination, and those who lived with high-risk adults were not significantly more likely to be vaccinated. Clinicians caring for high-risk adults should remind eligible household contacts to receive influenza vaccine.

U.S. Prepares H1N1 Vaccine Strategy

U.S. Prepares H1N1 Vaccine Strategy

Effects of Oseltamivir on Influenza-Related Complications in Children With Chronic Medical Conditions

This study investigated the influence of oseltamivir on influenza-related complications and hospitalizations for children and adolescents, 1 to 17 years of age, with chronic medical conditions or neurologic or neuromuscular disease. In a retrospective study, outcomes for patients who were given oseltamivir within 1 day after influenza diagnosis were compared with those for patients who received no antiviral therapy. Anonymous data from MarketScan databases (Thomson Reuters, Cambridge, MA) were used to identify patients from 6 influenza seasons between 2000 and 2006. The study outcomes were frequencies of pneumonia, respiratory illnesses other than pneumonia, otitis media, and hospitalization. Oseltamivir was prescribed for 1634 patients according to the study criteria, and 3721 patients received no antiviral therapy for their influenza. After adjustment for demographic and medical history variables, oseltamivir was associated with significant reductions in the risks of respiratory illnesses other than pneumonia, otitis media and its complications, and all-cause hospitalization in the 14 days after influenza diagnosis. Analyses for 30 days after influenza diagnosis also showed significant risk reductions for respiratory illnesses other than pneumonia, otitis media and its complications, and all-cause hospitalization with oseltamivir. When it was prescribed at influenza diagnosis, oseltamivir was associated with reduced risks of influenza-related complications and hospitalizations for children and adolescents at high risk of influenza complications.

Pharmacoeconomic evaluation of influenza vaccination programs in elderly in Italy

Background: influenza infection is an important cause of morbidity and mortality in the elderly population, especially in the presence of underlying disease. Vaccination has proven effective in the reduction of influenza-like illness (ILI) cases and influenza-related hospitalizations, drug consumption, primary care consultations and death. The aim of this study is to assess the economic impact in Italy of different prophylactic strategies (vaccination with a standard vaccine, with the innovative MF59® adjuvated vaccine and no vaccination) comparing their costs and outcomes in the elderly population. Methods: a pharmacoeconomic simulation model to estimate costs and consequences of influenza with the three intervention strategies has been developed. Health economics and demographic data are taken from specific Italian sources, and vaccine effectiveness data are taken from published literature. Direct sanitary costs are considered according to current prices and tariffes. Results: it was estimated that 9,800,000 of the about 12,000,000 people with at least 65 years currently resident in Italy can be considered at high risk for influenza complications because of underlying chronic diseases. Absence of vaccination could lead to more than 2 millions of ILI cases, and 30,000 related deaths. The reduction of cases attainable with the implementation of a vaccination program would lead to an estimated 1.5 million cases with a standard vaccine, and to 1.3 million with a strategy based on the MF59® adjuvated vaccine. The standard vaccination strategy could produce a moderate total cost increase of about € 45,000,000 (+4.3%), whereas the use of the adjuvated vaccine would lead to an estimated saving of about € 80,000,000 (-7.9%), both compared to the null option. Cost savings are mainly related to hospital admissions avoided with the use of vaccines. Incremental cost-effectiveness ratio (ICER) of the standard vaccine versus no vaccination strategy is of € 85.68 for each ILI episode avoided, and of € 4,411.42 for death avoided. The strategy based on the MF59® adjuvated vaccine dominates the other two options. Conclusions: vaccination with the MF59® adjuvated vaccine (Fluad®) results more effective and cost saving when compared with the standard vaccination or the no vaccination, thus representing the strategy of choice for the elderly population. Moreover, the standard vaccine proved to be largely cost effective with respect to the null option.

Childhood Influenza Vaccination Coverage—United States, 2004-05 Influenza Season

Children aged <2 years are at increased risk for influenza-related hospitalizations, and children aged 24-59 months are more likely than older children to visit a clinic, hospital, or emergency department with influenza-associated illness. In 2002, the Advisory Committee on Immunization Practices (ACIP) encouraged annual influenza vaccinations for children aged 6-23 months (and for household contacts of and out-of-home caregivers for children aged <2 years). For the 2004-05 influenza season, ACIP strengthened its encouragement to a full recommendation. For the upcoming 2006-07 influenza season, ACIP has further extended its recommendation to include all children aged 6-59 months (and their household contacts and out-of-home caregivers). Others recommended to receive influenza vaccination include children aged 6-18 years who have certain high-risk medical conditions, are on chronic aspirin therapy, or who are household contacts of persons at high risk for influenza complications. This report provides an assessment of influenza vaccination coverage among children aged 6-23 months during the 2004-05 influenza season. The findings demonstrate that vaccination coverage in that age group approximately doubled from the 2003-04 influenza season, with substantial variability among states and urban areas. However, the percentage of fully vaccinated children remained low, underscoring the need for increased measures to improve pediatric vaccination coverage and ongoing monitoring of coverage among young children and their close contacts.

Influenza update: NACI issues annual influenza prevention recommendations for the 2006/2007 season

Influenza update: NACI issues annual influenza prevention recommendations for the 2006/2007 season

Influenza vaccination coverage among children with high-risk medical conditions

We evaluated influenza vaccination coverage in children with chronic disease at high risk of influenza complications, and the need for methods to increase parents’ and pediatricians’ knowledge of influenza and its prevention. The 5286 children aged less than 14 years attending our Emergency Department on Wednesdays and Sundays between 1 January and 30 April 2003 included 274 (5.2%) high-risk patients. The use of influenza vaccine during the previous three seasons had been very low, but significantly increased in the last season (2000–2001, 5.1%; 2001–2002, 12.9%; 2002–2003, 26.3%; p<0.001). The children with asthma or cardiac disease showed the lowest vaccination rates; their parents and primary care pediatricians had only a marginal knowledge of influenza and the benefits of its prevention. In conclusion, the delivery of influenza vaccine to children with chronic disease at high risk of influenza complications is completely inadequate, and major efforts are urgently needed to increase parents’ and pediatricians’ knowledge of its importance.