20 years of PediSurv: a critical evaluation of a surveillance network for severe or rare infectious diseases in children in Belgium (2002–2023)

The Pediatric surveillance network, PediSurv, has been monitoring several rare or severe infectious diseases in children under 15 years in Belgium since 2002. The network collects clinical information in order to determine risk factors and evaluate vaccination strategies. Moreover, absence of disease is regularly reported to follow up international eradication and elimination targets set by the Word Health Organization. Over more than 20 years surveillance, the importance and purpose of the network has evolved significantly in the growing landscape of surveillance systems, digital transitions and changing epidemiology. In this paper, we critically assess the strengths and weaknesses of PediSurv and explore its future role in the Belgian surveillance system. We conducted a descriptive analysis based on initial study protocols, quality documents and reports to reconstruct historical transitions of the network. Trends between 2002 and 2023 were analyzed for number of participants, coverage and contribution of registrations compared with other existing data sources, and complemented with findings from a 2022 user experience survey. Digitalization and adoption of General Data Protection Regulation were transitions with the biggest impact on the network leading to stricter data governance requirements, including revised data collection procedures and increased administrative burden; this, in turn limiting data analysis and the flexibility of the network. Over 20 years, the number of participants gradually decreased. In parallel, case registrations decreased for most pathogens, especially relative to registrations in co-existing surveillance systems. However, in PediSurv, the degree of detail of clinical information remains high and it remains the unique data source to capture zero notifications. Participants cite importance for public health as the main motivation for participating. The surveillance landscape has drastically changed over the past 20 years, highlighting the need for existing systems to remain flexible and responsive to current and emerging public health needs. In the current Belgian context, whilst options for automatization are being investigated, manual reporting by physicians still offers added value. To ensure long-term engagement it is essential to sustain the motivation of participating physicians by clearly demonstrating the public health impact of surveillance systems and minimizing their reporting workload.