Oral Presentation Australian and New Zealand Stroke Organisation Conference 2026

Not just a sniffle – the impact of respiratory viruses as triggers for stroke (139687)

Tu Q Nguyen 1 2 , Lachlan L Dalli 3 , Tim Spelman 4 5 6 , Eric Zhao 1 , Ben D Atkins 1 , Aaron L Weinman 1 , Hazel J Clothier 1 2 7 , Suzanne Mavoa 1 2 7 , Monique F Kilkenny 3 , Christopher M Reid 8 9 , Jim P Buttery 1 2 10
  1. Murdoch Children's Research Institute, Parkville, VIC, Australia
  2. Department of Paediatrics, University of Melbourne, Parkville, VIC, Australia
  3. Stroke and Ageing Research, School of Clinical Sciences at Monash Health and Victorian Heart Institute, Monash University, Clayton, VIC, Australia
  4. Burnet Institute, Melbourne, VIC, Australia
  5. Adelaide Medical School, University of Adelaide, Adelaide, SA, Australia
  6. Centre for Health Services Research, Peter MacCallum Cancer Centre, Melbourne, VIC, Australia
  7. School of Population and Global Health, University of Melbourne, Parkville, VIC, Australia
  8. School of Population Health, Curtin University, Bentley, WA, Australia
  9. Centre for Cardiovascular Research and Education in Therapeutics, Monash University, Melbourne, VIC, Australia
  10. Department of Infectious Diseases, Royal Children's Hospital, Parkville, VIC, Australia

BACKGROUND: Infections have been linked as triggers for stroke; however, the magnitude of their contribution is unclear. To quantify their contribution, we examined the short-term population-level association between respiratory viruses and stroke and a potential spatiotemporal relationship.

METHODS: Statewide hospital admitted episodes for stroke in Victoria, Australia (June 2010 to December 2022) and contemporaneous laboratory-confirmed infections, meteorological, and air pollution datasets were analysed. Time-series analysis was used to model weekly stroke events and respiratory viruses (% tests positive); attributable fractions were calculated for associated pathogens using distributed lag nonlinear modelling. To examine spatiotemporal variation, the weekly association by Statistical Area Level 2 was modelled using a Bayesian Integrated Nested Laplace Approximation.

RESULTS: We analysed 153,730 stroke events (61% ischaemic; 25% haemorrhagic) and 6,180,896 respiratory specimens. In time-series analyses, higher circulating levels of specific respiratory viruses were associated with increased rates of stroke after controlling for seasonality, temperature and air pollution. The estimated fraction of strokes attributable to enterovirus was 4.6% (95% CI 2.5–6.6) and human metapneumovirus (hMPV) was 1.3% (95% CI 0.3–2.3), which rose to 3.5%–8.5% during weeks with high viral activity. The attributable pathogens differed between ischaemic stroke (hMPV 3.7%) and haemorrhagic stroke (enterovirus 5.8%; parainfluenza 3.2%). Spatiotemporal analysis revealed greater effect sizes in specific high-growth regional and outer urban areas.

CONCLUSIONS: Prevention of respiratory viral infections may reduce stroke occurrence in populations. People living in higher-risk areas during the peak seasons may be more susceptible to acute stroke.