Until now, the prevailing conventional wisdom was that China's coronavirus epidemic, which has spread to over 20,600 people around the globe as of February 3, did so by air or, according to some recent and unconfirmed speculation, human feces. That may be about to change.

Worker disinfects the lobby of Beijing West Railway Station in Beijing, capital of China, Feb. 2, 2020

According to the Global Times, new ways of transmitting the coronavirus have been reported, and virus nucleic acid has been detected outside human bodies, sparking public fears that the virus could be transmitted in unknown and undetected ways. Concerns emerged after scientists found coronavirus nucleic acid on the doorknob of a confirmed Guangzhou-based patient's house, the first case of novel coronavirus detected outside the human body, Guangzhou Daily reported Monday. The finding was confirmed by China's Health Commission, which said on Monday that the coronavirus can survive for five days maximum on smooth surfaces under suitable circumstances.

That would mean that mobile phone screens, computer keyboards, faucets and other household objects may indirectly transmit the virus, experts said.

A man from Northeast China's Jilin Province, who was confirmed with coronavirus infection on Monday, shared his experience, saying he had used the same microphone with another confirmed patient during a meeting in January.

In another case, a 40-year-old man from North China's Inner Mongolia Autonomous Region, who lives upstairs of a confirmed patient, was also diagnosed with coronavirus infection on Saturday. Aside from respiratory droplets and contact transmissions, the person has no clear contact histories with people from other cities, patients, or wild animals and has never been to a market, according to the local health authority on Sunday.

Chinese netizens were concerned the patient from Inner Mongolia might have been infected through toilet plumbing or ventilation devices.

Over the weekend, some experts warned that the novel coronavirus could be transmitted through the digestive system as they found 2019-nCoV nucleic acids in patients' stool and rectal swabs, and health authorities had suggested the central air conditioning system be discontinued if coronavirus patients are found. The case drew attention to a case during the SARS outbreak in 2003 - In Amoy Gardens residential complex in Hong Kong, aerosolized feces spread from floor to floor through plumbing, infecting over 300 people with the virus, reports said.