As the number of confirmed new coronavirus cases continues to grow outside China, concerns and questions about the virus have soared simultaneously.

By now, a total of 122 countries and regions have been infected, reporting over 51,700 cases and at least 1,775 deaths. 

Considering that COVID-19 is a new disease, global scientists and researchers are still learning how it spreads, the severity of illness it causes and everything about the contagious disease.

What we know is that it's possible the virus may spread through contact with contaminated surfaces or objects. But how long can the virus last on surfaces? How long can it survive without a living thing as its host?

According to a study published in the preprint database medRxiv on Wednesday, the virus was detected as viable in the air for up to 3 hours, on copper for up to 4 hours, and on cardboard for up to 24 hours.

It also indicated that the virus is most stable on plastic and stainless steel, on which it could be detected for up to 2 to 3 days.

However, researchers noted that the findings do not prove that people have been infected through breathing the virus in through the air or by touching contaminated surfaces. "It's theoretically possible," said study leader Neeltje van Doremalen at the National Institute of Allergy and Infectious Diseases.

The researchers also compared the results with another known human coronavirus, like the one that caused that SARS outbreak in 2003, and suggested that even though a similar result was obtained, it is not clear if the current novel coronavirus will behave in the same way.

Meanwhile Julie Fischer, a microbiology professor at Georgetown University, told the Associate Press that "It's a solid piece of work that answers questions people have been asking, and shows the value and importance of the hygiene advice that public health officials have been stressing."

"What we need to be doing is washing our hands, being aware that people who are infected may be contaminating surfaces," and keeping hands away from the face, she said.

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