5,000 volunteers signed up to test an experimental vaccine for the coronavirus.
The volunteers filled out an online survey and had to pass a medical check. Daily temperature and symptom checks are given to each patient.
The Oxford vaccine, as it has been dubbed, is made from a harmless virus that has been engineered to mimic the symptoms of the novel coronavirus.
The scientists are looking for an immune response to the experimental vaccine to see whether there are antibodies present. This way there can be a "herd" immunity to the coronavirus, like we have for diseases like the measles and mumps.
We may know by September if the experimental vaccine holds any promise.