Results from a European multicentre case-control study reported by Marta Valenciano and colleagues suggest good protection by the pandemic monovalent H1N1 vaccine against pH1N1 and no effect of the 2009–2010 seasonal influenza vaccine on H1N1.

In the fifth season of Influenza Monitoring Vaccine Effectiveness in Europe (I-MOVE), we undertook a multicentre case-control study (MCCS) in seven European Union (EU) Member States to measure 2012/13 influenza vaccine effectiveness against medically attended influenza-like illness (ILI) laboratory confirmed as influenza. The season was characterised by substantial co-circulation of influenza B, A(H1N1)pdm09 and A(H3N2) viruses. Practitioners systematically selected ILI patients to swab ≤7 days of symptom onset. We compared influenza-positive by type/subtype to influenza-negative patients among those who met the EU ILI case definition. We conducted a complete case analysis using logistic regression with study as fixed effect and calculated adjusted vaccine effectiveness (AVE), controlling for potential confounders (age, sex, symptom onset week and presence of chronic conditions). We calculated AVE by type/subtype. Study sites sent 7,954 ILI/acute respiratory infection records for analysis. After applying exclusion criteria, we included 4,627 ILI patients in the analysis of VE against influenza B (1,937 cases), 3,516 for A(H1N1)pdm09 (1,068 cases) and 3,340 for influenza A(H3N2) (730 cases). AVE was 49.3% (95% confidence interval (CI): 32.4 to 62.0) against influenza B, 50.4% (95% CI: 28.4 to 65.6) against A(H1N1)pdm09 and 42.2% (95% CI: 14.9 to 60.7) against A(H3N2). Our results suggest an overall low to moderate AVE against influenza B, A(H1N1) pdm09 and A(H3N2), between 42 and 50%. In this season with many co-circulating viruses, the high sample size enabled stratified AVE by type/subtype. The low estimates indicate seasonal influenza vaccines should be improved to achieve acceptable protection levels.

BackgroundImproving knowledge about influenza transmission is crucial to upgrade surveillance network and to develop accurate predicting models to enhance public health intervention strategies. Epidemics usually occur in winter in temperate countries and during the rainy season for tropical countries, suggesting a climate impact on influenza spread. Despite a lot of studies, the role of weather on influenza spread is not yet fully understood. In the present study, we investigated this issue at two different levels.MethodsFirst, we evaluated how weekly (intra-annual) incidence variations of clinical diseases could be linked to those of climatic factors. We considered that only a fraction of the human population is susceptible at the beginning of a year due to immunity acquired from previous years. Second, we focused on epidemic sizes (cumulated number of clinical reported cases) and looked at how their inter-annual and regional variations could be related to differences in the winter climatic conditions of the epidemic years over the regions. We quantified the impact of fifteen climatic variables in France using the Réseau des GROG surveillance network incidence data over eleven regions and nine years.ResultsAt the epidemic scale, no impact of climatic factors was highlighted. At the intra-annual scale, six climatic variables had a significant impact: average temperature (5.54 ± 1.09 %), absolute humidity (5.94 ± 1.08 %), daily variation of absolute humidity (3.02 ± 1.17 %), sunshine duration (3.46 ± 1.06 %), relative humidity (4.92 ± 1.20 %) and daily variation of relative humidity (4.46 ± 1.24 %). Since in practice the impact of two highly correlated variables is very hard to disentangle, we performed a principal component analysis that revealed two groups of three highly correlated climatic variables: one including the first three highlighted climatic variables on the one hand, the other including the last three ones on the other hand.ConclusionsThese results suggest that, among the six factors that appeared to be significant, only two (one per group) could in fact have a real effect on influenza spread, although it is not possible to determine which one based on a purely statistical argument. Our results support the idea of an important role of climate on the spread of influenza.Electronic supplementary materialThe online version of this article (doi:10.1186/s12889-016-3114-x) contains supplementary material, which is available to authorized users.

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Introduction: The risk of polypharmacy is on the rise in most industrialized countries, threatening to burden their health systems. Although many definitions exist and numerous concepts are found in literature as synonyms, the phenomenon of polypharmacy remains poorly defined. The aim of this literature review is to provide an overview of available definitions of polypharmacy, to analyse their convergences and divergences and to discuss the consequences on the assessment of the problem. Methods: A literature review was conducted to identify all published systematic reviews on definitions of polypharmacy available via Scopus and Pubmed databases. The Assessment of Multiple Systematic Reviews (AMSTAR) tool was used to appraise the methodological quality of the selected reviews. Available definitions and other characteristics were extracted; summarised in a table and analysed. Results: Six systematic reviews were identified. They were published between 2000 and 2018. Three focussed on definitions of polypharmacy in the elderly; two in the general population and one in children. The strategy adopted in reviews is more rigorous in the most recent ones. However, they remain, at best, partially exhaustive. The definitions found in the literature used two main approaches, either (i) quantitative, applying varying thresholds and types of polypharmacy based on the number of medications being taken by the patient (ii) qualitative, based on the clinical indications and effects of a given drug regimen, with a growing number of characteristics to describe polypharmacy. The term "inappropriate" is increasingly associated with polypharmacy especially in studies that aimed to use this definition to identify possible solutions for healthcare providers in the field related to aging. Conclusion: This review confirms a high variability and an evolution in the approaches defining "polypharmacy" in the absence of a consensus following standardized criteria. That makes it very difficult to estimate and measure the outcomes associated with this phenomenon.

Over a 2-month period, 43 of 143 participating general practitioners included 97 patients with 113 health impairments, mainly gastrointestinal problems (35%), respiratory tract infections (30%), and skin diseases (11%). Systemic febrile illness or imported tropical disease accounted for less than 4% of cases.

Understanding patterns of influenza spread and persistence is crucial for pandemic preparedness. The H1N1pdm09 virus caused the first influenza pandemic of the 21st century which resulted in at least 18500 deaths. Based on laboratory-confirmed primary-care case reports we investigated the role of weather conditions and socio-demographic variables in its initial spread and subsequent presence in France. Our findings suggest that low relative humidity and high population density were determinants in shaping the early spread of the virus at the national level. Those conditions also favoured the persistence of viral presence throughout the first 33 weeks of the pandemic. Additionally this persistence was significantly favoured by low insolation. These results confirm the increasingly recognized role of humidity in influenza dynamics and underlie the concomitant effect of insolation. Therefore climatic factors should be taken into account when designing influenza control and prevention measures.

Objectives - To describe the evolution of the SARS-CoV-2 salivary viral load of patients infected with Covid-19, performing 7 days of tri-daily mouthwashes with and without antivirals. - To compare the evolution of the SARS-CoV-2 nasal and salivary viral load according to the presence or absence of antivirals in the mouthwash. Trial design This is a multi-center, randomised controlled trial (RCT) with two parallel arms (1:1 ratio). Participants Inclusion criteria - Age: 18-85 years old - Clinical diagnosis of Covid-19 infection - Clinical signs have been present for less than 8 days - Virological confirmation - Understanding and acceptance of the trial - Written agreement to participate in the trial Exclusion criteria - Pregnancy, breastfeeding, inability to comply with protocol, lack of written agreement - Patients using mouthwash on a regular basis (more than once a week) - Patient at risk of infectious endocarditis - Patients unable to answer questions - Uncooperative patient The clinical trial is being conducted with the collaboration of three French hospital centers: Hospital Center Emile Roux (Le Puy en Velay, France), Clinic of the Protestant Infirmary (Lyon, France) and Intercommunal Hospital Center (Mont de Marsan, France). Intervention and comparator Eligible participants will be allocated to one of the two study groups. Intervention group: patients perform a tri-daily mouthwash with mouthwash containing antivirals (β-cyclodextrin and Citrox®) for a period of 7 days. Control group: patients perform a tri-daily mouthwash with a placebo mouthwash for a period of 7 days. Main outcomes Primary Outcome Measures: Change from Baseline amount of SARS-CoV-2 in salivary samples at 4 and 9 hours, 1, 2, 3, 4, 5 and 6 days. Real-time PCR assays are performed to assess salivary SARS-CoV 2 viral load. Secondary Outcome Measures: Change from Baseline amount of SARS-CoV-2 virus in nasal samples at 6 days. Real-time PCR assays are performed to assess nasal SARS-CoV-2 viral load. Randomisation Participants meeting all eligibility requirements are allocated to one of the two study arms (mouthwash with β-cyclodextrin and Citrox® or mouthwash without β-cyclodextrin and Citrox®) in a 1:1 ratio using simple randomisation with computer generated random numbers. Blinding (masking) Participants, doctors and nurses caring for participants, laboratory technicians and investigators assessing the outcomes will be blinded to group assignment. Numbers to be randomised (sample size) Both the intervention and control groups will be composed of 103 participants, so the study will include a total of 206 participants. Trial Status The current protocol version is 6, August 4th, 2020. Recruitment began on April 6, 2020 and is anticipated to be complete by April 5, 2021. As of October 2, 2020, forty-two participants have been included. Trial registration This trial was registered on 20 April 2020 at www.clinicaltrials.gov with the number NCT04352959. Full protocol The full protocol is attached as an additional file, accessible from the Trials website (Additional file 1). In the interest in expediting dissemination of this material, the familiar formatting has been eliminated; this Letter serves as a summary of the key elements of the full protocol.” The study protocol has been reported in accordance with the Standard Protocol Items: Recommendations for Clinical Interventional Trials (SPIRIT) guidelines (Additional file 2).”