Vaccine effectiveness against COVID-19 hospitalisation in adults (≥ 20 years) during Alpha- and Delta-dominant circulation: I-MOVE-COVID-19 and VEBIS SARI VE networks, Europe, 2021.

IntroductionTwo large multicentre European hospital networks have estimated vaccine effectiveness (VE) against COVID-19 since 2021.AimWe aimed to measure VE against PCR-confirmed SARS-CoV-2 in hospitalised severe acute respiratory illness (SARI) patients ≥ 20 years, combining data from these networks during Alpha (March-June)- and Delta (June-December)-dominant periods, 2021.MethodsForty-six participating hospitals across 14 countries follow a similar generic protocol using the test-negative case-control design. We defined complete primary series vaccination (PSV) as two doses of a two-dose or one of a single-dose vaccine ≥ 14 days before onset.ResultsWe included 1,087 cases (538 controls) and 1,669 cases (1,442 controls) in the Alpha- and Delta-dominant periods, respectively. During the Alpha period, VE against hospitalisation with SARS-CoV2 for complete Comirnaty PSV was 85% (95% CI: 69-92) overall and 75% (95% CI: 42-90) in those aged ≥ 80 years. During the Delta period, among SARI patients ≥ 20 years with symptom onset ≥ 150 days from last PSV dose, VE for complete Comirnaty PSV was 54% (95% CI: 18-74). Among those receiving Comirnaty PSV and mRNA booster (any product) ≥ 150 days after last PSV dose, VE was 91% (95% CI: 57-98). In time-since-vaccination analysis, complete all-product PSV VE was > 90% in those with their last dose < 90 days before onset; ≥ 70% in those 90-179 days before onset.ConclusionsOur results from this EU multi-country hospital setting showed that VE for complete PSV alone was higher in the Alpha- than the Delta-dominant period, and addition of a first booster dose during the latter period increased VE to over 90%.

Chronic use of inhaled corticosteroids in patients admitted for respiratory virus infections: a 6-year prospective multicenter study.

Inhaled corticosteroids (ICS) have been associated with increased risk of pneumonia. Their impact on respiratory virus infections is unclear. We performed a post-hoc analysis of the FLUVAC cohort, a multicenter prospective cohort study of adults hospitalized with influenza-like illness (ILI) during six consecutive influenza seasons (2012-2018). All patients were tested for respiratory virus infection by multiplex PCR on nasopharyngeal swabs and/or bronchoalveolar lavage. Risk factors were identified by logistic regression analysis. Among the 2658 patients included, 537 (20.2%) were treated with ICS before admission, of whom 282 (52.5%, 282/537) tested positive for at least one respiratory virus. Patients on ICS were more likely to test positive for non-influenza respiratory viruses (25.1% vs. 19.5%, P = 0.004), especially for adenovirus (aOR 2.36, 95% CI 1.18-4.58), and respiratory syncytial virus (aOR 2.08, 95% CI 1.39-3.09). Complications were reported in 55.9% of patients on ICS (300/537), primarily pneumonia (171/535, 32%). Among patients on chronic ICS who tested positive for respiratory virus, 14.2% (40/282) were admitted to intensive care unit, and in-hospital mortality rate was 2.8% (8/282). Chronic use of ICS is associated with an increased risk of adenovirus or RSV infections in patients admitted for ILI.

In-hospital and midterm post-discharge complications of adults hospitalised with respiratory syncytial virus infection in France, 2017-2019: an observational study.

OBJECTIVES: The purpose of this study was to describe the clinical characteristics and in-hospital and post-discharge outcomes of respiratory syncytial virus (RSV) infection among adults hospitalised with influenza-like illness (ILI) and compared against patients admitted for influenza. METHODS: Adults hospitalised with ILI were prospectively included from five French university hospitals over two consecutive winter seasons (2017/2018 and 2018/2019). RSV and influenza virus were detected by multiplex reverse transcription PCR on nasopharyngeal swabs. RSV-positive patients were compared to RSV-negative and influenza-positive hospitalised patients. Poisson regression models were used to estimate the adjusted prevalence ratio (aPR) associated with in-hospital and post-discharge outcomes between RSV and influenza infections. The in-hospital outcome was a composite of the occurrence of at least one complication, length of stay ≥7 days, intensive care unit admission, use of mechanical ventilation and in-hospital death. Post-discharge outcome included 30- and 90-day all-cause mortality and 90-day readmission rates. RESULTS: Overall, 1428 hospitalised adults with ILI were included. RSV was detected in 8% (114 of 1428) and influenza virus in 31% (437 of 1428). Patients hospitalised with RSV were older than those with influenza (mean age 73.0 versus 68.8 years, p=0.015) with a higher frequency of chronic respiratory or cardiac disease (52% versus 39%, p=0.012, and 52% versus 41%, p=0.039, respectively) and longer hospitalisation duration (median stay 8 versus 6 days, p<0.001). Anti-influenza therapies were less prescribed among RSV patients than influenza patients (20% versus 66%, p<0.001). In-hospital composite outcome was poorer in RSV patients (aPR 1.5, 95% CI 1.1-2.1) than in those hospitalised with influenza. No difference was observed for the post-discharge composite outcome (aPR 1.1, 95% CI 0.8-1.6). CONCLUSION: RSV infection results in serious respiratory illness, with worse in-hospital outcomes than influenza and with similar midterm post-discharge outcomes.

Vaccine effectiveness against COVID-19 hospitalization in adults in France: A test negative case control study.

BACKGROUND: Measuring vaccine effectiveness (VE) using real-life data is critical to confirm the effectiveness of licensed vaccine, which could strengthen vaccination adherence. METHODS: We measured VE against adult COVID-19 hospitalization in five hospitals in France using a test negative design. We compared the odds of vaccinated patients hospitalized with COVID-19 with the odds of vaccinated patients hospitalized for the same symptoms with a negative test. RESULTS: A total of 853 patients (463 cases and 390 controls) were included, with a total of 170 patients vaccinated (104 with one dose, 65 with two doses, and one with three doses). There were four cases of breakthrough infections, all in immunocompromised patients. The VE was 84.0% (CI0.95=[72.6; 90.6]) for one dose and 96.2% (CI0.95=[86.8; 98.9]) for two doses. CONCLUSION: Our results confirm the high VE of COVID-19 vaccine in France to prevent hospitalizations due to the alpha variant.

Non-influenza respiratory viruses in adult patients admitted with influenza-like illness: a 3-year prospective multicenter study.

PURPOSE: To describe the burden, and characteristics, of influenza-like illness (ILI) associated with non-influenza respiratory viruses (NIRV). METHODS: We performed a prospective, multicenter, observational study of adults admitted with ILI during three influenza seasons (2012-2015). Patients were screened for picornavirus, respiratory syncytial virus (RSV), coronavirus, human metapneumovirus, adenovirus, bocavirus, parainfluenza virus, and influenza, by PCR on nasopharyngeal samples. We excluded patients coinfected with NIRV and influenza. RESULTS: Among 1421 patients enrolled, influenza virus was detected in 535 (38%), and NIRV in 215 (15%), mostly picornavirus (n = 61), RSV (n = 53), coronavirus 229E (n = 48), and human metapneumovirus (n = 40). In-hospital mortality was 5% (NIRV), 4% (influenza), and 5% (no respiratory virus). As compared to influenza, NIRV were associated with age (median, 73 years vs. 68, P = 0.026), chronic respiratory diseases (53% vs. 45%, P = 0.034), cancer (14% vs. 9%, P = 0.029), and immunosuppressive drugs (21% vs. 14%, P = 0.028), and inversely associated with diabetes (18% vs. 25%, P = 0.038). On multivariable analysis, only chronic respiratory diseases (OR 1.5 [1.1-2.0], P = 0.008), and diabetes (OR 0.5 [0.4-0.8], P = 0.01) were associated with NIRV detection. CONCLUSIONS: NIRV are common in adults admitted with ILI during influenza seasons. Outcomes are similar in patients with NIRV, influenza, or no respiratory virus.

Factors associated with poor outcomes among adults hospitalized for influenza in France: A three-year prospective multicenter study.

BACKGROUND: Influenza is an important cause of serious illness and death, particularly in elderly and high-risk groups. OBJECTIVES: Aim of this study was to identify factors associated with poor outcomes among adults hospitalized in France for laboratory-confirmed seasonal influenza. STUDY DESIGN: Patients hospitalized for influenza were identified in a prospective, multicenter study carried out in French hospitals during three consecutive influenza seasons (2012-2015). Influenza virus infection was confirmed by reverse transcription polymerase chain reaction. Sociodemographic and clinical variables were compared according to the virus type and subtype. Risk factors for complications, intensive care unit (ICU) admission and death were analyzed by backward stepwise logistic regression. RESULTS: The study population consisted of 566 patients, of whom 56% were older than 65 years and 82% had underlying chronic illnesses. Type A influenza viruses infected 422 patients (75%), including subtype H3N2 in 239 patients (57%). The prior vaccine coverage rate was 38%. Complications occurred in 255 patients (45%), consisting mainly of pneumonia (n=143, 30%) and respiratory failure (n=116, 20%). Eighty-three patients (15%) were admitted to an ICU, and the in-hospital mortality rate was 4% (n=21). Sixty-six patients (12%) received oseltamivir. Age over 65 years was the only identified risk factor for complications. Risk factors for ICU admission were an absence of vaccination, no oseltamivir administration before admission, pre-existing chronic respiratory disease, and current smoking. Age over 65 years and ICU admission were risk factors for death. CONCLUSIONS: Older individuals and patients with underlying conditions are most at risk of influenza complications. Vaccination and early oseltamivir administration, both of which are recommended for these patients, appear to reduce ICU admissions.