What drugs are effective in treating the novel coronavirus? How is the vaccine development going? And where did the virus originate from?  

Below are the answers from officials and experts at a Joint Prevention and Control Mechanism of the State Council press conference on the progress of medical research against the virus on Saturday.  

Several drugs found effective in clinical trials 

Several drugs, including rendesivir, chloroquine phosphate and fapilavir, have been screened and have shown good clinical efficacy in treating the novel coronavirus, according to Zhang Xinmin, director of the China National Center for Biotechnology Development under the Ministry of Science and Technology. 

Rendesivir, a new antiviral drug by U.S. company Gilead that reportedly cured a patient in the U.S., has shown good inhibiting effects on the virus and quite a high level of safety in vitro experiments, Zhang said.  

The drug, originally aimed at infectious diseases like Ebola, has not hit the market yet because its clinical trials have not finished in the U.S. 

It is now undergoing clinical trials on patients in Wuhan for efficacy. "We are looking forward to the final results," Zhang said.  

Chloroquine phosphate, an antimalarial drug that has been on the market for many years, and fapilavir, an overseas marketed drug for flu, have also been found effective in clinical trials.  

"China has green-lighted all administrative passes to treat and cure the patients. But when it comes to science, the standard cannot be lowered, and the scientific procedures have to be followed to develop a new drug," said Zhou Qi, a professor at the Institute of Zoology of Chinese Academy of Sciences.  

No vaccine available worldwide yet 

No vaccine for the novel coronavirus is on the market so far, said Yan Jinghua, researcher at the Institute of Microbiology, Chinese Academy of Science (CAS).  

But the development of a vaccine has always been a main thrust, and multiple approaches have been used in it, said Zhang Xinmin, director of the China National Center for Biotechnology Development under the Ministry of Science and Technology (MOST).  

To speed up the research and development, "a number of candidate vaccines are under development in parallel, including an inactivated vaccine, a mRNA vaccine, a recombinant protein vaccine, a virus vector vaccine and a DNA vaccine," said Zhang. 

Currently, some vaccine varieties have entered the stage of animal testing. 

Read more:

Novel coronavirus vaccine: Animal tests started 
Science behind the virus: How long will it take to develop a COVID-19 vaccine?

"As a special product applied to healthy people, the safety of vaccine comes first," stressed Zhang, adding that and time is needed to develop safe and effective vaccine products. 

The development progress of each research team in China is basically in sync with the international progress, he said. 

Bats the most likely natural host for the coronavirus 

A study of the genome sequences of the coronavirus carried out by the Wuhan Institute of Virology of the CAS has found that bats are the most likely natural hosts, said Wu Yuanbin, director-general of the Department of Science and Technology for Social Development under MOST. 

The team at the China Animal Health and Epidemiology Center tested over 4,800 samples of pigs, birds, dogs, cats and other animals collected in recent years, all of which showed negative results. It was initially ruled out that the novel coronavirus originated from poultry and livestock, Wu said. 

A total of 585 environmental and animal samples collected from the Huanan Seafood Market, where the virus is believed to originate from, and several other fresh food markets in Wuhan have been detected by the Chinese Center for Disease Control and Prevention, and the results suggest that the outbreak may be linked to the wildlife trade, according to Wu. 

Virus tracing is essential to revealing the origin and evolution of the virus, eliminating the source of the epidemic and preventing the spread of the epidemic, he said.