Background: Respiratory syncytial virus (RSV) is an important cause of childhood hospitalizations. The aim of the study was to estimate the rates of RSV-related hospitalizations in children aged less than 5 years in Poland. Methods: This retrospective observational cohort study was based on data obtained from the National Health Fund in Poland regarding all acute respiratory tract infections and RSV-coded admissions of children (age < 5 years) to public hospitals between July 2015 and June 2023. Patients were stratified based on the following age groups: 0–1 month, 2–3 months, 4–6 months, 7–12 months, 13–24 months, and 25–60 months. Results: The number of RSV-related hospitalizations increased every season, both before and through the ending phase of the coronavirus disease 2019 (COVID-19) pandemic. The COVID-19 pandemic was associated with a shift in the seasonality pattern of RSV infection. Hospitalization rates per 1000 inhabitants were the highest for children aged 0–12 months, reaching 47.3 in the 2022/23 season. Within this group, the highest hospitalization rate was observed for children aged 2–3 months—94.9 in the 2022/23 season. During the ending phase of the COVID-19 pandemic, the observed increase in admission rates was 2-, 4-, and 5-fold the pre-COVID rate for children aged <12 months, 12–24 months, and 25–60 months, respectively. Conclusions: In Poland, RSV infections cause a significant burden in hospitalized children aged less than 5 years. RSV-related hospitalizations were most frequent in children aged less than 1 year. The COVID-19 pandemic was associated with a shift in the seasonality pattern of RSV infections. After the pandemic, more RSV-related hospitalizations were observed in older children (aged 13 months and older) vs. the pre-pandemic phase.

Background: Respiratory syncytial virus (RSV) is a leading cause of acute respiratory infections and hospitalisations in infants (age < 1 year) and young children. Little is known on RSV epidemiology and related inpatient healthcare resource use (HCRU) in Switzerland. Aim: To explore RSV-related hospitalisations, inpatient HCRU and medical costs in all age groups, and risk factors for infant hospitalisations in Switzerland. Methods: We used national hospital registry data from 2003 to 2021 identifying RSV cases with ICD-10-GM codes, and described demographic characteristics, HCRU and associated medical costs of RSV inpatients. The effect of risk factors on infant hospitalisation was estimated with logistic regression. Results: We observed a general increase and biannual pattern in RSV hospitalisations between 2003/04 and 2018/19, with 3,575 hospitalisations in 2018/19 and 2,487 in 2019/20 before numbers declined in 2020/21 (n = 902). Around two thirds of all hospitalisations occurred in infants. Mean (median) age was 118 (85) days in hospitalised infants and 74 (77) years in hospitalised adult patients (> 18 years); 7.2% of cases required intensive care unit stay. Mean inpatient medical costs were estimated at EUR 8,046. Most (90.8%) hospitalised infants with RSV were born after 35 weeks of gestation without bronchopulmonary dysplasia or congenital heart disease. Low birth weight, gestational age and congenital disorders were associated with a higher risk for hospitalisation. Conclusions: RSV leads to a substantial number of hospitalisations and peaks in hospital capacity utilisation. Measures to protect all infants from an RSV hospitalisation are essential in addressing this public health challenge.

Introduction: Respiratory syncytial virus (RSV) is a leading cause of lower respiratory tract infections (LRTIs) in young children. Additionally, RSV is associated with long‐term respiratory morbidities. This study evaluates acute and long‐term healthcare utilization (HCU) in infants hospitalized with RSV‐associated LRTI (RSV‐LRTI) compared to non‐RSV LRTI (Non‐RSV‐LRTI) in a nationwide cohort. Methods: A retrospective case‐control study used data from Clalit Healthcare Services (CHS), Israel's largest healthcare provider. Infants born between 2015 and 2023, admitted before 12 months of age with LRTI during the RSV season, were included. PCR confirmed RSV‐LRTI cases, while controls had negative RSV PCR and positive PCR for other respiratory viruses. Acute HCU was assessed within 30 days post‐discharge. Long‐term respiratory‐related HCU was evaluated up to 6 years of age. Statistical analyses included Poisson regression, adjusting for demographic and clinical potential confounders. Results: A total of 8626 infants were included, with 4,951 in the RSV‐LRTI group and 3675 in the Non‐RSV‐LRTI group. The adjusted acute HCUs were higher in RSV‐LRTI cases with increased systemic steroid use (IRR = 2.25, 95%CI: 1.94–2.62, p < 0.001) and short‐acting beta‐agonist use (IRR = 3.80, 95%CI: 3.36–4.30, p < 0.001). The adjusted long‐term HCU trends persisted, with significantly higher use of respiratory‐related medications and pediatric pulmonologist visits (IRR = 1.21, 95%CI: 1.06–1.40, p = 0.006) in the RSV‐LRTI group. Conclusion: This nationwide study highlights the substantial acute and long‐term HCU burden associated with RSV‐LRTI compared to Non‐RSV‐LRTI, underscoring the need for effective preventive strategies for all infants, especially in the first months of life.

Background: Respiratory syncytial virus (RSV) is one of the leading causes of lower respiratory tract illness and hospitalizations in children aged ≤5 years worldwide. The aim of this study was to characterize the Polish population of patients aged ≤5 years who were hospitalized due to RSV infection, focusing on their clinical and epidemiological characteristics as well as treatment patterns. Methods: This retrospective observational study was conducted between November 2023 and February 2024 in 41 hospitals with pediatric departments across Poland. Data from patients aged ≤5 years admitted due to RSV infection confirmed with antigen test or RT-PCR were collected. The dataset was weighted and extrapolated to allow conclusions applicable to the general population of patients aged 0–5 years hospitalized with RSV infection in Poland. Results: Data from 419 patients were analyzed. Over half (57.4%) were younger than 12 months, 84% were born at term, and 85.8% had no comorbidities. The most frequent manifestations of RSV infections were pneumonia (56.8%), bronchiolitis (35.9%), and bronchitis (12.4%). Viral co-infections were identified in 8% of patients. Regarding treatment, 21.1% of patients required respiratory support, 67.6% received inhaled steroid therapy, 61.5% were treated with antibiotics, 48.1% received beta2-mimetics and anticholinergics, and 44.3% underwent systemic steroid therapy. Conclusions: Our findings confirm that severe RSV primarily affects the youngest children with no comorbidities who do not present high risk conditions. To reduce the overall disease burden, preventive strategies should be offered to all children, not being limited to those in risk groups.

Parainfluenza virus (PIV) is a common cause of respiratory illness in children and immunocompromised adults, but little is known about its epidemiology or disease burden in the general adult population. This review evaluates published global epidemiological and disease burden for PIV in adults, including high‐risk patients (immunocompromised or with chronic illnesses), and identifies existing data gaps. A PRISMA systematic review of publications from 2014 to 2023 in PubMed reporting PIV prevalence and disease burden (including hospitalisations, mortality) in adults (≥ 18 years) and high‐risk patients was performed. Sixty‐five studies were included; which skewed towards Asia, Europe, and North America, highlighting a data gap in global PIV prevalence. Overall prevalence of PIV (all strains) ranged from 0 to 15.2% [median 2%] in the general adult population (not considered high‐risk but tested for infection). PIV3 was the most prevalent strain (0.6−15.2% [2.9]), followed by PIV4 (0.4−6.5% [1.9]), PIV1 (0.5−2.8% [1.1]), and PIV2 (0−2.9% [1.1]). PIV prevalence was generally higher in high‐risk adults (up to 41% in certain risk groups) and those aged ≥ 65. Mortality rates ranged from 2 to 40% in those high‐risk, while need for respiratory assistance ranged from 0.9% to 64.2% and hospitalisation from 3.7% to 45.3%. None of the studies reported cost‐related healthcare resource utilisation. Variability of study designs, data stratification, and patient populations in the selected studies challenged evaluating the true prevalence of PIV and its burden. PIV infection carries an underappreciated burden, with substantial morbidity and mortality risks, especially in high‐risk patients. Significant knowledge gaps exist regarding global prevalence and economic burden in the general adult population.

Background: Respiratory syncytial virus (RSV) is a leading cause of acute respiratory infection and hospitalization in young children. Despite its significant burden, prophylaxis for all young children has only recently become available. Understanding the disease burden among this population is critical to evaluate the potential impact of new prophylactic options. Methods: This case-cohort study used data from the Swedish national registers. However, 31,907 hospitalized RSV cases <60 months old and 95,697 age-matched comparators were included from 2006 to 2022. The study investigated patient characteristics, incidence, short- and long-term healthcare resource use, associated costs, mortality and associations with high-risk conditions. Results: Most cases (84.4%) were born at full-term and were otherwise healthy. RSV incidence ranged from 203.3 per 100,000 (2006–007) to 708.4 per 100,000 (2021–2022), with the highest rates in children 1–<2 months of age. RSV accounted for 27.0% of all hospitalized acute respiratory infection cases. In the 30 days following index, 61.8% of RSV cases had an outpatient care visit, compared to 12.0% of comparators, and short-term care costs for cases totaled €27 million in 2021-2022. In the 12 months following index, 87.6% of RSV cases had an outpatient care visit, while 47.1% of comparators did. Mortality among RSV cases was low (30-day Kaplan–Meier survival: 1.00, 95% CI: 1.00–1.00). Conclusions: RSV hospitalization imposes a significant burden on young children in Sweden, most of whom are otherwise healthy. These findings support the adoption of prophylactic immunization strategies targeting all infants to mitigate this burden.