The sixth person has died from a new kind of virus that causes symptoms similar to SARS, a hospital in the U.K. said in a statement Tuesday.
This is the 12th known case of illness caused by the virus, a new kind of coronavirus, since it appeared last year in the Middle East. It's the first death reported in the U.K. Five others have occurred in Jordan and Saudi Arabia.
The patient, who was being treated at the Queen Elizabeth Hospital in Birmingham, England, had a chronic health condition and weakened immune system, which made him more vulnerable to the virus and the severe pneumonia-like problems it causes.
The man was thought to have caught the bug from his father, who is currently being treated for the virus in the intensive care unit of a hospital in Manchester, England.
The father had traveled to Saudi Arabia and Pakistan and returned to the U.K. in late January.
Health officials have already tracked down nearly 100 people who came in contact with him, including those who sat next to him on a plane back to the U.K., the BBC reported. No one, except his son, has gotten seriously ill.
A third family member also caught the virus, the U.K.'s Health Protection Agency said Friday, but the person experienced only mild respiratory problems and fully recovered at home.
The virus, which is also known as NCoV, is a distant cousin of SARS, which killed nearly 800 people in 2003.
But the new coronavirus isn't very contagious. "It appears very difficult to spread, and very difficult to catch," Dr. Paul Cosford, deputy chief of the HPA, told the BBC last week. "That's the big difference between this virus and the SARS virus."
Health officials say the risk of to the general population is low.
"Although [for] the people who get it, it is very serious for them, there is not a picture here that looks like SARS," Cosford said.
It's still not known where the new virus originated, but its genetic code sequence is most similar to that of a bat coronavirus. It's thought the virus jumps from bats to humans, either directly or through another animal.
Immunologists are already trying to figure out how the virus infects people. A team from Kantonal Hospital in Switzerland published a study Tuesday showing that the new coronavirus easily infects cells from the human respiratory tract.