Closing in on the virus behind China’s new pneumonia outbreak.

Scientific American and STAT (with the help of the World Health Organization) inch us a little closer to identifying the microbe behind the mysterious outbreak of pneumonia in Wuhan:

“Coronaviruses are a large family of viruses that range from the common cold to SARS. Some cause less-severe disease, some more severe. Some transmit easily from person to person, while others don’t,” the WHO statement said.

The virus can cause severe illness in some patients, the agency said, adding that it does not “transmit readily” between people. Earlier statements from the Wuhan Municipal Health Authority said there has been no person-to-person spread—a claim disease experts say is impossible to make at this stage in the exploration of a new disease.

The type of illness and the fact that it is emerging in China — where a number of SARS-like and other coronaviruses have been isolated from bats—has pointed in that direction.

Experts said it will now be important for China to share more information, including enough of a genetic sequence so that health facilities outside of China know what to look for when faced with a pneumonia case with a recent travel history to Wuhan.

As it currently stands, Hong Kong is isolating any such cases until they can be tested for influenza, rhinoviruses, and other viruses that cause colds and flu. Given it is flu season in the Northern Hemisphere, telling countries to be on the look out for travelers with fevers and cold-like symptoms casts a very broad net.

It will also be critical to figure out how the virus transmitted to people. The outbreak has been linked to a large seafood market that also sells live exotic animals for consumption. The market was closed and decontaminated on Jan. 1.