Characteristics of human metapneumovirus infection in adults hospitalized for community-acquired influenza-like illness in France, 2012-2018: a retrospective observational study.

OBJECTIVES: To describe the prevalence, clinical features and complications of human metapneumovirus (hMPV) infections in a population of adults hospitalized with influenza-like illness (ILI). METHODS: This was a retrospective, observational, multicenter cohort study using prospectively collected data from adult patients hospitalized during influenza virus circulation, for at least 24 h, for community-acquired ILI (with symptom onset <7 days). Data were collected from five French teaching hospitals over six consecutive winters (2012-2018). Respiratory viruses were identified by multiplex reverse transcription polymerase chain reaction (RT-PCR) on nasopharyngeal specimens. hMPV + patients were compared with hMPV- patients, influenza+ and respiratory syncytial virus (RSV)+ patients using multivariate logistic regressions. Primary outcome was the prevalence of hMPV in patients hospitalized for ILI. RESULTS: Among the 3148 patients included (1449 (46%) women, 1988 (63%) aged 65 and over; 2508 (80%) with chronic disease), at least one respiratory virus was detected in 1604 (51%, 95% confidence interval (CI) 49-53), including 100 cases of hMPV (100/3148, 3% 95% CI 3-4), of which 10 (10%) were viral co-infection. In the hMPV + patients, mean length of stay was 7 days, 62% (56/90) developed a complication, 21% (14/68) were admitted to intensive care unit and 4% (4/90) died during hospitalization. In comparison with influenza + patients, hMPV + patients were more frequently >65 years old (adjusted odds ratio (aOR) = 3.3, 95% CI 1.9-6.3) and presented more acute heart failure during hospitalization (aOR = 1.8, 95% CI 1.0-2.9). Compared with RSV + patients, hMPV + patients had less cancer (aOR = 0.4, 95% CI 0.2-0.9) and were less likely to smoke (aOR = 0.5, 95% CI 0.2-0.9) but had similar outcomes, especially high rates of respiratory and cardiovascular complications. CONCLUSIONS: Adult hMPV infections mainly affect the elderly and patients with chronic conditions and are responsible for frequent cardiac and pulmonary complications similar to those of RSV infections. At-risk populations would benefit from the development of antivirals and vaccines targeting hMPV.

Barriers and motivations for participation in preventive vaccine clinical trials: Experience of 5 clinical research sites.

Recruitment in preventive vaccine trials (PVT) is challenging due to common barriers to clinical research and lack of vaccine confidence. Identifying determinants of participation can help to improve recruitment. A prospective survey was conducted in 5 French clinical investigational sites. People asked to participate in a PVT were given a questionnaire whether they decided to participate or not in the trial. A total of 341 people answered the survey: 210 accepting and 131 declining to participate in a PVT. Acceptors were significantly younger (38.5 vs 54.9 years old), more likely to be involved in early phase trials, had a higher level of education (p < 0.005) and a significantly better general opinion concerning vaccines (92.3% versus 72.3%, p < 0.005) compared with those who declined. Factors associated with acceptance or refusal were evaluated in 224 people in the 4 sites where both groups were included. In a multivariate analysis, three factors: older age, having heard about PVT through multiple sources and financial incentives were significantly associated with refusal to participate in the PVT. A generally favourable opinion of vaccines was associated with acceptance. The main motivation for participation was altruism (93.2%) whereas fear of side effects was at the forefront of the barriers (36.6%). Information given by the physician was a key point for decision-making in 70.2% of those who accepted. In brief, vaccine hesitancy may decrease recruitment in PVTs; reinforcing altruism and quality of information given are key points in acceptance of participation in PVT.

Clinical characteristics and outcome of respiratory syncytial virus infection among adults hospitalized with influenza-like illness in France.

OBJECTIVES: The aim of this study was to analyse characteristics and outcome of respiratory syncytial virus (RSV) infection in adults hospitalized with influenza-like illness (ILI). METHODS: Patients hospitalized with ILI were included in this prospective, multicentre study carried out in six French hospitals during three consecutive influenza seasons (2012-2015). RSV and other respiratory viruses were detected by multiplex PCR in nasopharyngeal swabs. Risk factors for RSV infection were identified by backward stepwise logistic regression analysis. RESULTS: A total of 1452 patients hospitalized with ILI were included, of whom 59% (861/1452) were >65 years and 83% (1211/1452) had underlying chronic illnesses. RSV was detected in 4% (59/1452), and influenza virus in 39% (566/1452). Risk factors for RSV infection were cancer (adjusted OR 2.1, 95% CI 1.1-4.1, p 0.04), and immunosuppressive treatment (adjusted OR 2.0, 95% CI 1.1-3.8, p 0.03). Patients with RSV had a median length of stay of 9 days (6-25), and 57% of them (30/53) had complications, including pneumonia (23/53, 44%) and respiratory failure (15/53, 28%). Fifteen per cent (8/53) were admitted to an intensive care unit, and the in-hospital mortality rate was 8% (4/53). Pneumonia was more likely to occur in patients with RSV than in patients with RSV-negative ILI (44% (23/53) versus 26% (362/1393), p 0.006) or with influenza virus infection (44% versus 28% (157/560), p 0.02). CONCLUSION: RSV is an infrequent cause of ILI during periods of influenza virus circulation but can cause severe complications in hospitalized adults. Risk factors for RSV detection in adults hospitalized with ILI include cancer and immunosuppressive treatment. Specific immunization and antiviral therapy might benefit patients at risk.