A UK Health Security Agency (UKHSA) study with AI sleep technology company Sleep Cycle, reported on 3 September 2026, evaluated whether cough data passively collected by a sleep app could give early indications of rising respiratory illness in England. The study found the data provided a robust, regionally consistent indicator of community respiratory illness and early signals for influenza and COVID-19 activity, the agency said.

Researchers found app cough data closely reflected respiratory illness levels reported through NHS 111. Increases in coughing were often observed around one week before rises in influenza and COVID-19 activity, according to the study. UKHSA said existing surveillance relies on people seeking care through the NHS and can be affected by healthcare-seeking behaviour, service availability, demographic and socioeconomic differences, and reporting and laboratory processing times.

Sleep Cycle is a smartphone app that uses AI-powered sound analysis; its cough signal is collected passively during normal sleep and updated daily. Professor Steven Riley, UKHSA Chief Data Officer, said the findings suggest combining established surveillance with digital health signals could contribute to an earlier, richer understanding of population respiratory health. The study's authors and Sleep Cycle's Dr Mikael Kågebäck also described the potential for consumer-generated data to complement existing systems. The research concerns cough signals as an indicator, not diagnosis.