Influenza burden, prevention and treatment in asthma – a scoping review by the EAACI Influenza in Asthma Task Force

To address uncertainties in the prevention and management of influenza in people with asthma, we performed a scoping review of the published literature on influenza burden; current vaccine recommendations; vaccination coverage; immunogenicity, efficacy, effectiveness and safety of influenza vaccines; and the benefits of antiviral drugs in people with asthma. We found significant variation in the reported rates of influenza detection in individuals with acute asthma exacerbations making it unclear to what degree influenza causes exacerbations of underlying asthma. The strongest evidence of an association was seen in studies of children. Countries in the European Union currently recommend influenza vaccination of adults with asthma; however, coverage varied between regions. Coverage was lower among children with asthma. Limited data suggest that good seroprotection and seroconversion can be achieved in both children and adults with asthma and that vaccination confers a degree of protection against influenza illness and asthma related morbidity to children with asthma. There were insufficient data to determine efficacy in adults. Overall, influenza vaccines appeared to be safe for people with asthma. We identify knowledge gaps and make recommendations on future research needs in relation to influenza in patients with asthma

Impact of neuraminidase inhibitors on influenza A(H1N1)pdm09-related pneumonia: An individual participant data meta-analysis

Background: The impact of neuraminidase inhibitors (NAIs) on influenza-related pneumonia (IRP) is not established. Our objective was to investigate the association between NAI treatment and IRP incidence and outcomes in patients hospitalised with A(H1N1)pdm09 virus infection. Methods: A worldwide meta-analysis of individual participant data from 20 634 hospitalised patients with laboratory-confirmed A(H1N1)pdm09 (n = 20 021) or clinically diagnosed (n = 613) 'pandemic influenza'. The primary outcome was radiologically confirmed IRP. Odds ratios (OR) were estimated using generalised linear mixed modelling, adjusting for NAI treatment propensity, antibiotics and corticosteroids. Results: Of 20 634 included participants, 5978 (29\ub70%) had IRP; conversely, 3349 (16\ub72%) had confirmed the absence of radiographic pneumonia (the comparator). Early NAI treatment (within 2 days of symptom onset) versus no NAI was not significantly associated with IRP [adj. OR 0\ub783 (95% CI 0\ub764-1\ub706; P = 0\ub7136)]. Among the 5978 patients with IRP, early NAI treatment versus none did not impact on mortality [adj. OR = 0\ub772 (0\ub744-1\ub717; P = 0\ub7180)] or likelihood of requiring ventilatory support [adj. OR = 1\ub717 (0\ub771-1\ub792; P = 0\ub7537)], but early treatment versus later significantly reduced mortality [adj. OR = 0\ub770 (0\ub755-0\ub788; P = 0\ub7003)] and likelihood of requiring ventilatory support [adj. OR = 0\ub768 (0\ub754-0\ub785; P = 0\ub7001)]. Conclusions: Early NAI treatment of patients hospitalised with A(H1N1)pdm09 virus infection versus no treatment did not reduce the likelihood of IRP. However, in patients who developed IRP, early NAI treatment versus later reduced the likelihood of mortality and needing ventilatory support