The common cold is caused by a type of virus called a coronavirus. As you might expect, it’s everywhere. However, while some types can be harmless, others are not. Another type of coronavirus was blamed for the deadly SARS outbreak ten years ago. Now the World Health Organization is warning of a new deadly strain that originated in the Middle East but is now being found in patients in Europe. More than half of all known infections involving this particular strain have been fatal.
According to reports, the strain was first identified in a 60-year-old patient in Jeddah, Saudi Arabia in June. Tests at a laboratory in Rotterdam in the Netherlands confirmed that it was a new type of coronavirus in September. The new strain, coronavirus 2c EMC/2012 or “Saudi SARS,” has affected more than a dozen people and may yet sicken still more.
The good news is that, unlike SARS—and the common cold—person-to-person transmission is reportedly rare and difficult. It does spread between individuals; the first British patient, a man living in Manchester who had traveled to Pakistan and the Middle East and who died of the infection on February 19th, apparently passed it to his son. However, this is the only known case of contagion, and it does not appear poised to spread rapidly through contact.
However, because the virus is so new, and there are so few patients, precisely how it is spread is not clear. What researchers have found is that the strain is genetically similar to viruses found in bats, though that may not be the method of transmission. Scientists have figured out how the virus, once acquired, makes its way into cells to cause the respiratory symptoms and renal failure characteristic of the infection.
In particular, while it does not appear to involve the same pathway SARS was found to use in 2003, the new virus uses a newly discovered protein called dipeptidyl peptidase 4, or DPP4. This protein is very similar in humans and bats, as well as pigs, monkeys, and other wild and domesticated mammals. This discovery is an important step on the road to a treatment or a vaccine; it suggests that attacking it at the protein site could prove effective.