As of 8 May 2013, 30 laboratory-confirmed cases of human infection with novel coronavirus (nCoV) have been reported to WHO: two from Jordan, two from Qatar, 23 cases from Saudi Arabia, two from the United Kingdom (UK), and one from the United Arab Emirates.
Most patients are male (79.3%; 23 of 29 cases with sex reported) and range in age from 24 to 94 years (median 56 years). The first cases had onset of illness in late March or early April 2012; the most recent cases reported had onset on 1 May 2013 (13 cases with onset 14 April - 1 May 2013).
Most patients presented with severe acute respiratory disease requiring hospitalization and eventually required mechanical ventilation or other advanced respiratory support. Eighteen patients have died.
Several cases have occurred in clusters, including in a health care setting in Jordan in April 2012 (of 2 confirmed and 11 probable cases, 10 were health care workers) and in the UK among family members of an infected patient who had recently arrived from Saudi Arabia.
The Jordanian outbreak illustrated the potential of this virus to spread through health care facilities and the UK outbreak confirmed the potential of the virus to transmit between humans with close contact. In neither instance did transmission appear to go beyond the immediate outbreak into the community.
Since 14 April 2013, 13 new cases of infection have been confirmed and reported in Saudi Arabia (10 males and 3 females, median age 58 years). Seven of these have died, four remain critically ill in intensive care and two are hospitalized but clinically improved. All patients were reported to have at least one comorbid medical condition and most had more than one.
Most of the cases were patients at a single health care facility. Two were family members of two patients from that facility; no health care workers have been affected. Although investigations are still ongoing into the source of this outbreak, early information indicated that only a small minority of these cases had contact with animals in the time leading up to their illness.
Five viruses from the United Kingdom (n=2), Saudi Arabia (n=1), Jordan (n=1), and Germany (n=1) have been cultured and genome sequences have been made publicly available. No sequence data are yet available from the latest cluster. All five of the sequenced viruses have a high degree of genetic similarity.
Preliminary analyses show that the viruses are genetically somewhat similar to bat viruses. It should be noted, however, that the similarity does not necessarily imply that bats are the reservoir for the human virus or that direct exposure to bats or bat excreta were responsible for infection. The nCoV itself has not yet been found in an animal.