Prospective longitudinal study of respiratory syncytial virus and other respiratory viruses in children <5 years in community settings in metropolitan western Australia: the PATROL study

Introduction Respiratory syncytial virus (RSV) is a significant cause of respiratory infections in young children. Since 2021, RSV has been a notifiable disease in Australia. However, current surveillance systems focus on hospitalised RSV, with limited surveillance at a community level through primary care clinics. This approach only captures RSV requiring hospitalisation. Less severe illnesses, while not captured, may have significant social and economic impacts including the associated cost of care and absenteeism. The aim of this study is to establish an understanding of the broader burden of RSV in young children in a community setting. Methods and analysis The PATROL (Parents Actively Tracking RSV in Little Ones) project is a prospective longitudinal observational study of RSV and other respiratory viruses in children <5 years in community settings in metropolitan Perth, Western Australia. Over a 12-month surveillance period, parent/guardians will collect a mid-nasal swab from their child any time they meet the case definition or during one of the four screening points aligned with key points in the RSV season. Swabs will be tested for RSV and other respiratory viruses by PCR, with results returned to the parent/guardian. Rapid antigen tests for RSV, SARS-CoV-2 and Influenza A/B are provided for at-home testing in addition to PCR. Symptoms are reported by parents/guardians using MyCap, a phone-based application for REDCap. Incidence rates of RSV illness and asymptomatic carriage will be calculated and compared with the incidence rate ratios of other respiratory viruses. Ethics and dissemination The Government of Western Australia Child and Adolescent Health Service Human Research Ethics Committee approved all study materials. Results and findings will be disseminated through manuscripts, conference abstracts and presentations, participant newsletters and appropriate general news media items.