Impact of respiratory viral co-infections on RSV disease burden in children (<5 years) in primary care over five European countries: a retrospective analysis of RSV ComNet data

Duration: Apr 2025 - Sep 2026

Background

Respiratory syncytial virus (RSV) is the leading cause of acute lower respiratory tract infections in children. By the age of one year, 60-70% of children are infected with RSV and almost all children are infected by the age of two years. In western countries, mortality from RSV is rare. The rate of hospitalization in young children is estimated at 0.6 to 42.7 cases per 1000 children, with higher rates in younger children. Noticeable, incidence rates were higher in primary care—ranging from 0.8 to 330 (median=109) per 1000 compared to emergency departments (7.5–144.0, median=48). The previous RSV ComNet study found that children seeking primary care have substantial health care use for the RSV infection resulting in considerable costs. Important, notable differences in health care utilization and costs existed between countries. Moreover, that study showed almost one third of children with RSV do have a respiratory viral co-detection.

Aim

In this retrospective analysis, the focus lies on the impact of respiratory viral co-infections. The primary research question is whether the disease burden is different for young children with only an RSV infection and children with RSV and an additional respiratory viral co-infection. This knowledge is critical for policy makers to make informed decisions about the introduction of new RSV interventions.

Method, Project design

The data were collected in the RSV ComNet study. Eligible children were children who consulted the GP or primary care pediatrician with acute respiratory infection (ARI) symptoms. Data were collected in Italy, Spain, Belgium, UK and the Netherlands. A swab was taken and tested with multiplex PCR for respiratory viruses, except in the Netherlands where no multiplex testing was performed. During this consultation, the physician filled in a short report form about the condition of their child i.e. current symptoms and underlying conditions. Parents, whose children were tested positive for RSV , were asked to fill in the questionnaire at day 14 and day 30.

Result

The results will be described in a report and scientific manuscript. 

More information

More information at the Nivel website: Project RSV Comnet
More information at the international website: www.orchid.phc.ox.ac.uk/index.php/rsvcomnet2/