Assessing the Burden of Respiratory Syncytial Virus-related Bronchiolitis in Primary Care and at 15-Day and 6-Month Follow-up Before Prophylaxis in France: A Test-negative Study.

OBJECTIVE: To assess the burden of respiratory syncytial virus (RSV)-related bronchiolitis in primary care and at 15 days and 6 months after a primary care visit. STUDY DESIGN: In this test-negative study, children <2 years old with a first episode of bronchiolitis were prospectively enrolled by 45 ambulatory pediatricians in France from February 2021 to April 2023. RSV was assessed with a rapid antigen detection test. The burden of the disease was assessed with a questionnaire, including quality of life (PedsQL 1.0 Infant Scales), at 15-day and 6-month follow-up. Children with a positive RSV test result (RSV+) were compared to those with a negative test result (RSV-). RESULTS: Among the 1591 children enrolled, 750 (47.1%) were RSV+. At 15 days follow-up (data availability: 69%), as compared with RSV- children, RSV+ children more frequently had fever (20.5% vs. 13.7%, P = 0.004) and decreased food intake (27.0% vs. 17.4%, P < 0.001) during the last 3 days. They had higher rates of hospitalization (11.8% vs. 5.8%, P < 0.001), childcare absenteeism (83.5% vs. 66.1%, P < 0.001) and parents who had to stop working to care for them (59.1% vs. 41.0%, P < 0.001) as well as lower quality of life (median PedsQL score 76.2 vs. 78.4, P = 0.03). At 6 months (data availability: 48.5%), the 2 groups did not differ in proportion of medical attendance, hospitalization, antibiotic treatment or quality of life. CONCLUSION: RSV+ children experienced much more severe disease and follow-up family and societal burden than RSV- children. These data may be used as baseline data as RSV prophylaxis is about to be implemented.

Assessment of effectiveness and impact of universal prophylaxis with nirsevimab for prevention of hospitalizations due to respiratory syncytial virus in infants. The NIRSE-GAL study protocol.

Nirsevimab has been recently licensed for universal RSV prophylaxis in infants. NIRSE-GAL is a three-year population-based study initiated in Galicia in September 2023. It aims to evaluate nirsevimab effectiveness against RSV-related hospitalizations lower respiratory tract infections (LRTI), severe RSV, all-cause LRTI, and all-cause hospitalization. NIRSE-GAL also aims to estimate nirsevimab impact on primary healthcare use in the short and mid-term, children's wheezing and asthma, and medical prescriptions for RSV. The immunization campaigns will be scheduled based on the expected start week for the RSV season and will last the whole season. Immunization will be offered to: i) infants born during the campaign (seasonal), ii) infants < 6 months at the start of the campaign (catch-up), and iii) infants with high-risk factors, aged 6-24 months at the start of the campaign (high-risk). The follow-up period will start: i) the immunization date for all immunized infants, ii) the start of the campaign, for the non-immunized catch-up or high-risk groups, or iii) the birthdate for the non-immunized seasonal group. Infants will be followed up until outcome occurrence, death, or end of study. Nirsevimab effectiveness will be estimated using Poisson and Cox regression models. Sensitivity and stratified analyses will be undertaken. The number of averted cases and the number needed to immunize will be estimated. Immunization failure and nirsevimab safety will be monitored. NIRSE-GAL was approved by the ethics committee of Galicia (CEIC 2023-377) and registered in ClinicalTrials.gov (ID: NCT06180993). Findings will be mainly shared via peer-reviewed publications and scientific conferences.

Effectiveness of Immunization Products Against Medically Attended Respiratory Syncytial Virus Infection: Generic Protocol for a Test-Negative Case-Control Study.

Monitoring the real-life effectiveness of respiratory syncytial virus (RSV) products is of major public health importance. This generic protocol for a test-negative design study aims to address currently envisioned approaches for RSV prevention (monoclonal antibodies and vaccines) to study effectiveness of these products among target groups: children, older adults, and pregnant women. The generic protocol approach was chosen to allow for flexibility in adapting the protocol to a specific setting. This protocol includes severe acute respiratory infection (SARI) and acute respiratory infection (ARI), both due to RSV, as end points. These end points can be applied to studies in hospitals, primarily targeting patients with more severe disease, but also to studies in general practitioner clinics targeting ARI.

Prevalence of chronic conditions and influenza vaccination coverage rates in Germany: Results of a health insurance claims data analysis.

BACKGROUND: The significant annual burden caused by seasonal influenza has led to global calls for increased influenza vaccination coverage rates (VCRs). We aimed to estimate the proportion of the German population at high risk of serious illness from influenza due to chronic conditions and to estimate age-specific VCRs of people with/without chronic conditions. METHODS: Using health insurance claims data covering nine influenza seasons (2010-2019), we assessed up to 7 million insured individuals per season across all German regions. Individuals were classified according to age and presence of chronic health conditions. VCRs were estimated using outpatient healthcare utilization documentation. RESULTS: In the 2018-2019 influenza season, 47.3% of individuals had ≥1 chronic condition. Most common were circulatory disorders, accounting for more than a third of individuals with ≥1 condition. Prevalence of chronic diseases, and therefore the proportion of high-risk individuals, increased slightly over time across most age groups. A downward trend in influenza VCRs was observed in all age groups until the 2017-2018 season, followed by a noticeable increase in the 2018-2019 season. Highest VCRs occurred among individuals of ≥60 years, with a 38.5% VCR for this age group in the 2018-2019 season. Several factors, including age, chronic condition type, and geographical location, affected VCRs. CONCLUSIONS: Influenza VCRs in individuals at high risk of severe complications from influenza infection are insufficient. Our results suggest that intensified public health efforts are necessary to reach the World Health Organization vaccination coverage target of 75%.

Cost and burden of RSV related hospitalisation from 2012 to 2017 in the first year of life in Lyon, France.

OBJECTIVES: We aimed to describe direct medical costs of annual RSV-associated hospitalisation in the first year of life. METHODS: Retrospective cohort study in Lyon, France (2012-2016). A case was defined as a laboratory confirmed RSV-infection with hospitalisation in the first year of life. Hospital costs were estimated based on the French version of Diagnosis Related Groups. RESULTS: Overall, 350 cases in 21,930 children were identified. Incidence of RSV-associated hospitalisation in the first year of life per 1000 births was 14.5 (95% CI 13.4-15.6). Related direct medical annual costs were 364,269 €, mostly attributed to children born during the RSV season (231,959 €) and children born premature (108,673 €). CONCLUSION: Medical costs for RSV-associated hospitalisation of newborns are higher for children born premature or born during the RSV season. Prioritised targeting of those groups may facilitate a cost-efficient strategy for the national prevention program.