GUANGZHOU, Feb. 13 (Xinhua) -- Two separate research groups led by China's top scientists said they had isolated novel coronavirus strains from samples of infected patient's feces.

Researchers from multiple organizations, including the State Key Laboratory of Respiratory Disease under Guangzhou Medical University, have successfully isolated a strain of virus from swab sample of an infected patient's feces, said Zhao Jincun, a professor with the laboratory, at a press conference Thursday.

The swab sample was provided by the Fifth Affiliated Hospital of Sun Yat-Sen University, said Zhao, also a member of the research group of Chinese respiratory expert Zhong Nanshan.

Meanwhile, a research team led by Li Lanjuan from the State Key Laboratory for Diagnosis and Treatment of Infectious Diseases also isolated three novel coronavirus strains from five stool specimens of infected patients, according to Wu Nanping, deputy director of the laboratory.

"We made the discoveries in the laboratory, which still need further confirmation by epidemiologists. More scientific researches are also entailed concerning the level of infectivity and whether the virus in feces was swallowed by patients or from intestinal cell proliferation, as well as its relationship with blood, sputum and the occurrence and development of diseases," Wu said.

According to Zhao, the discovery confirmed that the patients' feces contained the live virus, though it still lacks sufficient evidence for the existence of fecal-oral transmission.