Young people who have previously had Covid-19 are going to be deliberately exposed to the virus for a second time as part of a trial run by the University of Oxford.
The new study will aim to see how young people’s immune system will react, and hope to discover what dose of coronavirus is needed to cause reinfection. The results of the study will aim to help develop protective immunity against the disease.
In the University of Oxford’s “human challenge” trial, participants will be quarantined for 17 days and cared for by researchers at a hospital until they are no longer at risk of infecting others. Participants will receive just under £5,000 as payment.
Human challenge studies have played a key role in furthering the development of treatments for diseases including malaria, tuberculosis, typhoid, cholera and flu.
Professor Helen McShane, the chief investigator, said: "Challenge studies tell us things that other studies cannot because, unlike natural infection, they are tightly controlled.
"When we reinfect these participants, we will know exactly how their immune system has reacted to the first COVID infection, exactly when the second infection occurs, and exactly how much virus they got.
"As well as enhancing our basic understanding, this may help us to design tests that can accurately predict whether people are protected."
How will the study work?
The study will take place in phases.
The first phase, involving 64 healthy volunteers, will aim to establish the lowest dose of virus which can take hold and start replicating.
Once the dosing amount is established, it will be used to infect participants in the second phase of the study, which is expected to start in the summer.
Regular check-ups in the year after reinfection will help establish the immune response generated by the virus - and this could contribute to the creation of better vaccines, and a greater understanding of how long immunity lasts.
Who can take part in the study?
The trial is open to people aged 18 to 30 years old who have previously been naturally infected with Covid.
The participants will be recruited and re-exposed to the virus in a safe, controlled environment.
Participants will be quarantined for 17 days and cared for by researchers at a hospital until they are no longer at risk of infecting others, and they will receive just under £5,000 as payment.