The UK Health Security Agency (UKHSA) and AI sleep technology company Sleep Cycle have published the results of a study looking at cough data from a sleep app could give early indications of increasing respiratory illness in England.
The results show that the passive data collected can provide a robust and regionally consistent indicator of community respiratory illness while also providing early signals for influenza and COVID-19 activity.
The study found that cough data collected through the app closely reflected levels of respiratory illness reported through NHS 111. Rises in coughing were often seen around a week before increases in flu and COVID-19 cases.
The Sleep Cycle app is designed to help people understand and improve their sleep through AI-powered sound analysis. The cough signal is generated automatically during normal sleep using privacy-preserved, passively collected data and updated daily, providing a near real-time view of respiratory illness activity.
The results showed that used alongside established surveillance systems, passive sleep monitoring could provide a fuller picture of respiratory surveillance data, helping public health experts better understand seasonal trends sooner.
Professor Steven Riley, Chief Data Officer at UKHSA, said: "These findings suggest that combining established surveillance approaches with novel digital health signals could contribute to an earlier, richer and more resilient understanding of population respiratory health.
"No single surveillance system provides a complete picture of respiratory disease activity, but this shows that passive nocturnal cough monitoring can complement other surveillance systems to provide a timely population-level signal of upcoming disease trends, without being affected by healthcare-seeking behaviour, laboratory turnaround times, backfilling and reporting delays."
Dr. Emil Carlsson, Research Scientist & Co-lead Author, said: "This study demonstrates that passively collected nightly cough data captures meaningful changes in community respiratory illness.
"Equally important, it shows that consumer-generated health data can be transformed into epidemiologically meaningful surveillance signals using rigorous scientific methods while maintaining strong privacy protections.
Dr. Mikael Kågebäck, Chief Technology Officer and Acting Chief Executive Officer at Sleep Cycle, said: "This study validates a completely new category of health data.
"For the first time, we’ve demonstrated that passively generated smartphone data can produce robust population-level health intelligence at national scale, while also providing earlier signals for influenza and COVID-19 activity.
"That creates opportunities to strengthen public health surveillance and enable researchers, healthcare organisations and industry partners to build new services for situational awareness and operational decision support."
