Although influenza is a major public health concern, little is known about the use of spray live attenuated influenza vaccine (LAIV) among adults. For this reason, we conducted a systematic review and meta-analysis to investigate the efficacy and safety of LAIV, especially in adults with/without clinical conditions and children <2 years, with the final aim of possibly extending the clinical indications. PubMed/MEDLINE and Scopus were the two databases consulted through February 2021. The Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines were followed. A critical appraisal was conducted. Analyses were performed by using ProMeta3 software. Twenty-two studies were included, showing that LAIV was associated with a higher probability of seroconversion when compared with a placebo and considering the A/H1N1 serotype (pooled OR = 2.26 (95% CI = 1.12–4.54), p-value = 0.022; based on 488 participants, without heterogeneity (I2 = 0.0%)). The meta-analysis also confirmed no significant association with systemic adverse events. Only rhinorrhea, nasal congestion, and sore throat were significantly associated with LAIV compared to the placebo. Despite limited available evidence, LAIV has proved to be a safe and effective flu vaccination, also due to its very low invasiveness, and our review’s results can be considered a starting point for guiding future research and shaping forthcoming vaccination campaigns.

Diabetic patients are at higher risk of developing infectious diseases and severe complications, compared to the general population. Almost no data is available in the literature on influenza immunization in people with type 1 diabetes mellitus (T1DM). As part of a broader project on immunization in diabetic patients, we conducted a cross-sectional study to: (i) report on seasonal influenza coverage rates in T1DM patients, (ii) explore knowledge, attitudes, and practices (KAPs) towards seasonal influenza in this population, and (iii) identify factors associated with vaccine uptake, including the role of family doctors and diabetologists. A survey was administered to 251 T1DM patients attending the Diabetes Clinic at San Raffaele Research Hospital in Milan, Italy and individual-level coverage data were retrieved from immunization registries. Self-reported seasonal influenza immunization coverage was 36%, which decreased to 21.7% when considering regional immunization registries, far below coverage target of 75%. More than a third (36.2%) of T1DM patients were classified as pro-vaccine, 30.7% as hesitant, 17.9% as uninformed, and 15.1% as anti-vaccine. Diabetologists resulted to be the most trusted source of information on vaccines’ benefits and risks (85.3%) and should be more actively involved in preventive interventions. Our study highlights the importance of developing tailored vaccination campaigns for people with diabetes, including hospital-based programs involving diabetes specialists.

Background Patients with type 1 (T1DM) and type 2 (T2DM) diabetes are at increased risk of vaccine-preventable diseases and their complications. The National Vaccinal Prevention Plan 2017-2019 includes specific recommendations for patients with diabetes, which in 2018 have been included in the standards of care of the Italian Diabetes Society (SID) and Italian Association of Clinical Diabetologists (AMD). Methods Adult diabetic patients attending the Diabetes clinic at the San Raffaele Hospital, a large teaching hospital in Milan, Italy, were surveyed with a questionnaire to investigate self-reported vaccinal history, knowledge, attitudes and practice on the recommended vaccinations, vaccinal hesitancy and information sources on the topic. Results Between May 16 and November 11, 2019 N = 222 T1DM and N = 57 T2DM patients were enrolled. 25.2% of T1DM and 26.3% of T2DM patients did get vaccinated annually against the flu in the past 3 year. 85.0% of T2DM patients were vaccinated at the General Practitioner's (GP) clinic, while 54.9% of T1DM patients were vaccinated by their GP and 24.4% from territorial vaccinal clinics. 54.5% of T1DM and 50.0% of T2DM patients chose not to be vaccinated because they didn't consider the vaccine useful, while the second most common reason was that they have not been advised by healthcare personnel. Conclusions We documented a low coverage and knowledge about influenza vaccination. Patients with diabetes trusted information and advice of diabetologists and GPs about vaccination and claimed that they would be more likely to vaccinate if vaccination were offered in the diabetes clinic. Implementing training programs for professionals and educational campaigns for patients with diabetes may improve vaccinal coverage. Key messages Vaccination coverage in T1DM and T2DM patients is low due to vaccination hesitancy. A strong action from care givers, in order to raise vaccination awareness in this at-risk population, is needed.