Some of you may have heard about a new coronavirus isolated from humans sick with severe respiratory symptoms. I did a search and found that it was mentioned in the overnight news digest from Sept. 24, but from what I could find it has not been discussed at length on the site. Quite a bit of information has been released in the press, so I thought since this is in my general field of study, I might put together a quick diary about what is known about the virus.
Coronaviruses are enveloped, positive-sense, single-stranded RNA viruses that infect birds and mammals. Known human coronaviruses cause about a third of the upper respiratory infections ("colds") in humans. These infections are generally self-limiting, although occasionally they can become more severe, particularly in younger, older, or immunocompromised individuals. Coronaviruses are spread via contact with secretions or aerosol droplets from infected individuals.
What is known about the new coronavirus as of today is below the squiggly.
On June 13 a 60 year old man was admitted to a hospital in Saudi Arabia with pneumonia. He had respiratory disease symptoms for 7 days before going to the hospital. He developed acute renal failure and died on June 24. The virus was isolated by culturing on human cells, and was identified as a coronavirus using polymerase chain reaction by Ali Mohamed Zaki at the Virology Laboratory of Dr Soliman Fakeeh Hospital in Jeddah Saudi Arabia. The viral RNA was further tested in the laboratory of Dr. Ron Fouchier in the Netherlands, and confirmed to be a coronavirus, and further shown to be closely related to known bat coronaviruses. The findings were posted on ProMED (Program for Monitoring Emerging Diseases)-mail, which is an internet-based reporting system for disseminating information about infectious disease outbreaks, on Sept. 20.
Early in September, a 49 year old Qatari man who had recently traveled to Saudi Arabia, was admitted to the hospital with severe respiratory illness. In the hospital he developed renal failure. He was moved by air ambulance to the UK where tests showed he was infected with a coronavirus. Sequencing of a small 250 nucleotide region of the virus he was infected with showed it was 99.5% similar (1 nucleotide change) to the virus isolated from the Saudi man. This patient is currently still in intensive care.
Phylogenetic analysis of the new coronavirus shows that it is a bat coronavirus, and is not SARS. However, because it is a bat coronavirus (as was SARS), there is some concern that it may be able to spread rapidly among humans. The World Health Organization has therefore released a case definition and issued a global alert.
As of this time, there is no evidence that the virus is spreading from human to human, and no additional cases have been reported. There was a report of 5 people in Denmark who had recently traveled to Saudi Arabia with a severe respiratory disease, but these people were found to be infected with influenza. It is possible that no additional cases will be found, however, because of the severity of the disease, and our fairly recent experiences with the SARS outbreak, the authorities are likely being very proactive in attempts to prevent what could be a public health emergency. This virus may be of particular concern because of the upcoming Hajj pilgrimage to Mecca in Saudi Arabia, which, at least for now, appears to be where the virus was acquired by the two known patients.
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