A new coronavirus from the same family as SARS has now infected six people in the Middle East, two of whom have died, the World Health Organization announced Friday.

The UN health agency said four new cases have been confirmed, in addition to a previous patient from Saudi Arabia, who died in June, and another one from Qatar still undergoing treatment in the United Kingdom.

Three of the new cases are Saudis - and two are family members who lived together, the WHO said in a news release. One died and the other is recovering.

Two other relatives of that family have also shown the pneumonia-like symptoms of the novel coronavirus. One relative died but laboratory results have not yet confirmed whether he or she had the virus; the second relative is recovering and tested negative.

The fourth of the new cases is a Qatari citizen, according to the WHO. On Friday, Germany's national health institute also announced a German clinic had been treating a Qatari patient with the novel coronavirus, who fell ill in October and was released this week.

So far, there is no evidence that the virus is easily transmitted between humans, as was the case with the deadly SARS outbreak in 2003 that swept across 30 countries and killed approximately 800 people, including 44 Torontonians. It is possible that animals were the source of infection and early investigations show that the novel coronavirus is closely related to one found in bats.

Nevertheless, the case of the Saudi Arabian family with multiple illnesses is raising some flags.

"The timing of the cases in the Saudi cluster does raise that concern (of human-to-human transmission)," said WHO spokeswoman Fadéla Chaib. "But when a cluster occurs in a setting such as a household, where everyone has similar environmental exposures, it can be very difficult to separate out exposure to the same environmental source versus spread from one person to another.

"Investigations are ongoing to try and answer this question, however, if (human-to-human transmission) has occurred, it does not appear to be sustained."

As a precaution, the WHO is now urging increased surveillance for the novel coronavirus, recommending that all patients with unexplained pneumonias be tested, even those who have not recently travelled to Saudi Arabia or Qatar.

"Until more information is available, it is prudent to consider that the virus is likely more widely distributed than just the two countries which have identified cases," the WHO said.

The deadly potential of coronaviruses first became apparent in 2003 with the outbreak of SARS. The virus, named for its crown-like appearance, had been previously associated with the common cold.

This new coronavirus - given the scientific name HCoV-EMC - first emerged over the summer, although scientists at the time did not know what it was.

The first recognized patient, a 60-year-old man in Saudi Arabia, was hospitalized on June 13 with pneumonia and died eleven days later. A second case - a Qatari man airlifted to a London hospital - was confirmed in late September.