New research provides important insights into the role played by the immune system in preventing – and in some cases increasing the severity of – COVID-19 symptoms in patients. It also finds clues to why some people experience ‘long COVID’.
Among the key findings, which have not yet been peer-reviewed, are:
Individuals who have asymptomatic or mild disease show a robust immune response early on during infection.
Patients requiring admission to hospital have impaired immune responses and systemic inflammation (that is, chronic inflammation that may affect several organs) from the time of symptom onset.
Persistent abnormalities in immune cells and a change in the body’s inflammatory response may contribute to ‘long COVID’.
"Our evidence suggests that the journey to severe COVID-19 may be established immediately after infection, or at the latest around the time that they begin to show symptoms"