A third person in Britain has contracted a new virus similar to SARS, making it the second confirmed British case in a week and demonstrating that the infection is being spread from person to person.
The deadly infection was first seen in the Middle East and affected those who had lived or traveled in the area.
The latest British case is a man who is thought to have contracted it from a family member who also had it. The worldwide total of confirmed cases of novel coronavirus, or NCoV, is 11.
It was identified last year in September by the World Health Organization, who issued an international alert saying a new virus had infected a man from Qatari. The man recently visited Saudi Arabia.
NCoV is in the same family as Severe Acute Respiratory Syndrome, or SARS, which emerged in 2002 in China and killed a tenth of the 8,000 people infected.
They have similar symptoms, which include severe respiratory illness, fever, coughing and breathing difficulties.
The man who was most recently infected had no history of traveling to the Middle East and is currently in an intensive care unit in England.
“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,” John Watson, HPA head of respiratory diseases, said.
Watson also said that the world should not be concerned just yet, as the transmission rate seems to be very low.
Despite it being less contagious, Tom Wilkinson, senior lecturer in respiratory medicine, also warned that viruses mutate constantly. The virus could change quickly and become extremely contagious.
"But it's early days to make any definite statements because viruses can change and mutate very rapidly, so what is right today may be wrong tomorrow," Wilkinson said.
The World Health Organization said all member states should continue surveillance for infections and investigate unusual patterns.
“Testing for the new coronavirus should be considered in patients with unexplained pneumonias, or in patients with unexplained severe, progressive or complicated respiratory illness not responding to treatment,” they said in a statement.