Simulation Features Enterovirus EV-D68, Modeled as Pig-Origin
Respiratory Virus Primarily Affecting Children
The United Kingdom recently concluded “Exercise Pegasus,” the largest pandemic simulation in nearly a decade, involving broad government and health agencies nationwide. The simulated outbreak used a novel virus modeled on enterovirus EV-D68, thought to have originated in pigs and primarily causing severe respiratory illness and deaths in children.
Exercise Pegasus was led by the UK Department of Health and Social Care in partnership with NHS England, UK Health Security Agency, and local resilience forums across all devolved governments and regions.
The exercise spanned three core phases between September and November 2025, simulating emergence, containment, and mitigation stages of the pandemic response.
All 38 Local Resilience Forums in England participated, alongside national and regional NHS command structures, with ministerial involvement and COBR (Cabinet Office Briefing Rooms) activations included.
The chosen virus for simulation, enterovirus EV-D68, belongs to a family of viruses known for causing mild illnesses but capable of serious neurological complications like acute flaccid paralysis, predominantly in children.
While enteroviruses naturally occur, the scenario posited EV-D68 as a zoonotic virus derived from pigs with a high mortality rate in children to test healthcare system stress and response capabilities.
During Exercise Pegasus, NHS and government entities tested readiness in communication, resource allocation, coordination across agencies, and implementation of emergency health measures.
Lessons learned will inform updated Pandemic Response Plans that focus on layered control measures and address inequalities and information accuracy challenges.
The UK government plans to publish comprehensive reports summarizing the exercise’s outcomes as part of ongoing pandemic preparedness reforms inspired by COVID-19 experiences and prior simulations.
