Respiratory Syncytial Virus (RSV) is the most commonly identified respiratory pathogen in young children and is most often associated with bronchiolitis and in severe cases, pneumonia. RSV is a World Health Organization priority for prevention through vaccination with several promising candidates now in late-stage clinical trials. There are epidemiological knowledge gaps that need to be filled in the pre-vaccine era. Additionally, since the start of the COVID-19 pandemic, the typical seasonal patterns of RSV have altered, highlighting further unanswered questions on the epidemiology of RSV.
Record linkage of population-based administrative data on an individual basis has provided the opportunity to further our knowledge of the epidemiology of pre-COVID RSV in children. Through combining data from perinatal, socio-demographic, hospitalisation, and microbiological testing data over 12 years in Western Australia, we have developed a statistical prediction model to improve disease incidence rates of RSV-hospitalisations. Laboratory testing for RSV is not routine among children admitted to hospital for respiratory infections, leading to an under appreciation of the burden using only laboratory-confirmed data. Using predictors of RSV test positivity and extrapolating to those hospitalisations without a laboratory test record, we estimated that true RSV incidence rates could be 30-57% higher than laboratory-confirmed data, revealing this hidden burden. We are planning to refine this prediction model on a contemporary set of linked data. Through further linkages with childhood immunisation data, we have been afforded the opportunity to explore the non-specific effects of routine infant immunisations on RSV disease incidence. This has included suggested protective effects of pneumococcal vaccination on risk of RSV disease in young children. Record linkage mechanisms provide a platform to further our epidemiological knowledge of RSV, which is particularly important with future prevention products close to market and uncharacteristic seasonal patterns following COVID-19. Further public health research areas for RSV currently being undertaken including community awareness studies and refining dynamic transmission models.