Researchers in Guangzhou on Friday said pangolins are a possible “intermediate host” of the novel coronavirus that has killed more than 630 people in China. 

The South China Agricultural University  scientists said the genetic sequence of virus strains they separated from pangolins were 99 percent identical to those from people infected with the virus.

“This latest discovery will be of great significance for the prevention and control of the origin (of the virus),” they said in a statement.

The university’s principal, Liu Yahong, said her research team believed the virus might have spread from bats to humans through pangolins after identifying more than 1,000 genomic samples. 

The samples were from animals including pangolins, a scaly anteater-like creature that is one of the world’s most trafficked mammals. 

The novel coronavirus broke out at a market in Wuhan where live wild animals were on sale in December 2019. Scientists believe the virus originated from bats but that intermediate hosts may have passed the virus to humans. 

Scientists discovered after the outbreaks of Severe Acute Respiratory Syndrome (Sars) and Middle East Respiratory Syndrome (Mers) that viruses in bats often need an intermediate host to jump to humans. 

The intermediate host for Sars is the civet, and for Mers is the camel.

The market is an important clue to the traceability of coronavirus. But the area has now been cleaned and disinfected meaning main evidence is likely gone.

There are now more than 34,900 confirmed cases globally and the death toll in China has surpassed 720. 

Shen Yongyi, a professor who participated in the research, said the chances that people were infected directly from bats was “very little” since the outbreak occurred in winter, when the creatures stay in caves.

“Therefore, the intermediate host may be the source of the virus,” professor Shen Yongyi said. 

Last month, a Chinese scientific team stated that mink and snake may be intermediate hosts of the disease.

The university has not released complete research data. Spokesperson Chen Pengchen told reporters that the team is still writing and revising the research. 

Some academics are skeptical about the result of the research. According to Caixin.com, a researcher from the Chinese Academy of Sciences received a viral gene sequence isolated from the pangolins by the South China Agricultural University’s research team. 

She said about 4,000 of the sample’s nucleotides - basic building blocks of DNA - have not been sequenced. The new coronavirus has approximately 29,410 nucleotides, so further analysis is needed to conclude pangolins are a host, she added. 

When asked during a press conference Friday where the pangolin samples used for the research came from, one of the researchers, professor Feng Yaoyu, declined to say. 

The researchers “did not have the privilege of obtaining large quantities of pangolin samples” but hope to get more to verify the results, she said. 

She said the batch of pangolins was a special group that showed symptoms. Whether it can infect humans is currently unclear and requires further research, she added.

The International Union for the Conservation of Nature says that pangolins have become the most trafficked mammals in the world.

Last year, more than 30 journalists across 15 countries and territories conducted a joint investigation on how illegal pangolin trafficking is leading the species to extinction. 

• Across Myanmar, pangolins are trafficked in plain sight

The pangolin is a second-level protected animal in China and among class-1 most protected animals in Myanmar. Many of them were trafficked in plain sight or smuggled into China from Myanmar to feed demand for traditional Chinese medicine.

At a seminar in August last year, officials from China’s Wildlife and Plant Protection Department said they were trying to upgrade pangolins to a class-1 most protected animal. 

Chinese authorities in January put a ban on the wildlife trade as one of the measures to curb the spread of coronavirus. 

Xu Jiaming is a Guangzhou-based journalist who has worked for Southern Metropolis Weekly and Southern Weekly, two leading national publications. He covered politics, social issues and legal matters. He is a lead reporter of the Pangolin Reports series.