Emerging SARS-Like Virus Well-Suited to Attack Humans

The new SARS-like "coronavirus" that first emerged in the Middle East can invade the lungs and immune system as easily as the common cold, according to a recent study.

But in the event of a large-scale outbreak, researchers in Switzerland found the virus-known as HCOV-EMC-may be treatable with components of the immune system, known as interferons. This immunotherapy has shown promise in the treatment of the respiratory disease SARS and hepatitis C, the study authors said.

"Surprisingly, this coronavirus grows very efficiently on human epithelial cells," said study coauthor Volker Thiel, PhD, of the Institute of Immunobiology at Kantonal Hospital in St. Gallen, in a news release from the American Society for Microbiology. Epithelial cells line hollow organs and glands.

"The other thing we found is that the viruses [HCOV-EMC, SARS, and the common cold virus] are all similar in terms of host responses: they don't provoke a huge innate immune response," he said.

The study was published online in mBio.

HCOV-EMC, which may have jumped from animal to human very recently, was first isolated in Spring 2012 after a man in Saudi Arabia died from a severe respiratory infection and kidney failure. Following his death, health officials identified 11 more people infected with the virus, the latest in Great Britain. As of early 2013, seven people with known infections have died. Nearly all patients have lived or traveled in the Middle East.

Concerns have been raised that the new strain could trigger a pandemic similar to the SARS outbreak of 2002-2003, which infected more than 8,000 people and killed 774.

"We don't know whether the cases we observed are the tip of the iceberg, or whether many more people are infected without showing severe symptoms," noted Dr. Thiel.

Is That a Germy Toothbrush?

Is it true that you should replace your toothbrush after a cold or the flu?

A toothbrush does not typically carry enough germs to make you sick. Even if a virus from a recent illness is lingering on your toothbrush, you've developed antibodies to it, so the chance of reinfection is very small. But it's best to always follow good hygiene practices, especially after an illness. Choose a soft or ultrasoft toothbrush...rinse it thoroughly...and let it air dry after brushing. Store your toothbrush standing up in a container that does not cover the bristles. Replace your toothbrush every three to four months or when it starts to look frayed.

The World Health Organization said that doctors should test patients for the new coronavirus if they have unexplained pneumonia or unexplained complicated respiratory illness not responding to treatment.

As of February 2013, no cases of the coronavirus have been reported in the United States, according to the US Centers for Disease Control and Prevention.

To test the new virus, the researchers used cultured bronchial cells to mimic the lining of the human airway. The study authors found that pre-treating the airway with proteins that play a critical role in immune response to infections–known as lambda-type interferons—significantly reduced the number of infected cells.

Although their findings suggest there is promise for an effective treatment against HCOV-EMC, the researchers added ongoing cooperation between scientists and health agencies around the world is needed to prevent outbreaks of this virus and other diseases.