Health officials in the UK have said that a new respiratory illness similar to the deadly Sars virus can spread from person to person.
One man in the UK is thought to have caught the infection from his father, but officials say the threat to the whole population remains very low.
There have been 11 confirmed cases of the infection around the world and five patients have died. It causes pneumonia and sometimes kidney failure, the BBC reported.
The new patient, who is being treated in intensive care at the Queen Elizabeth Hospital in Birmingham, is the third case identified in the UK. The first was a patient flown in from Qatar for treatment. The second was linked to travel to the Middle East and Pakistan.
The virus is then thought to have spread from the second patient to his son, but there have been no signs of the virus spreading to staff at the hospital.
Person to person transmission was suggested in earlier cases in the Middle East, but this was not confirmed.
"Confirmed novel coronavirus infection in a person without travel history to the Middle East suggests that person-to-person transmission has occurred, and that it occurred in the UK," said Prof John Watson, head of the respiratory diseases department at the Health Protection Agency (HPA).
"Although this case provides strong evidence for person to person transmission, the risk of infection in most circumstances is still considered to be very low," he added.
Though the exact source of the new virus and how it spreads is still unknown, a leading theory suggests that it comes from animals, the new Sars-like virus does appear to be closely related to bats.
However, if the virus could readily and easily spread between people then far more cases than the 11 detected so far would have been detected.
The very small number of cases strongly suggests if it does pass between people, it is not very contagious. (ANI)