Two prisoners are being reportedly tested for coronavirus in Oxfordshire with eight people now being treated in the UK.
The men are inmates at HMP Bullingdon, near Bicester, and are being kept in isolation in their cells, reports Sky News.
It says access is being restricted to one wing where the prisoners are.
The prison, which has capacity for 1,114 inmates, remains running as usual and Public Health England are on site helping to manage the situation.
HMP Bullingdon holds both prisoners on remand and who have been sentenced, as well as young adults between the ages of 18-21.
One of its housing blocks accommodates sex offenders.
It also has a dedicated healthcare unit to support men with "complex medical requirements, mental health problems and primary care needs".
As the prisoners were being tested, the World Health Organisation announced the new coronavirus will be called COVID-19 - and the first vaccine could be ready in 18 months.
Eight people in the UK have been confirmed as having coronavirus, with the last four testing positive on Monday.
One of the latest people to become infected is thought to be a GP from a Brighton practice.
The first two people to have tested postive for the virus in York were sent to Newcastle's Royal Victoria Infirmary for treatment.
A total of 1,358 people have been tested in the UK.
