The new coronavirus behind the pandemic now affecting the global population closely resembles the virus that caused the outbreak of the SARS epidemic in China 17 years ago and was not a surprise, according to a specialist at a leading research center that studied the virus.
Kenneth Plante, associate director of the World Reference Center for Emerging Viruses and Arboviruses, a repository of viruses at University of Texas Medical Branch in Galveston, has been studying the virus since early February.
The center is a central dissemination point for supplying virus samples and has sent about a hundred samples to other research institutes.
Both SARS viruses originated from bats in China and mutated in ways that allowed infections in humans, he said.
Scientists have determined that the current virus known as severe acute respiratory syndrome coronavirus-2, or SARS CoV-2, is similar to another SARS virus began in China in 2003.
“The interesting thing about this virus is that it does mimic its sibling, the standard SARS coronavirus,” Mr. Plante said in an interview.
Researchers have learned much about the new virus and are working to validate how similar its characteristics are to the 2003 SARS virus.
“Some people have been hypothesizing this virus coming out for years,” Mr. Plante said. “And when it finally did come out, it came out pretty close to what people would expect it to emerge as.”
Mr. Plante said there are signs the virus is mutating from its original form. “It’s not really clear if they have any direct impact on the virulence or the transmissibility,” he said.
“This virus has been actually remarkably stable in our hands,” he noted. “But there is a possibility that we could see some further mutations that could change the phenotype [characteristics] of this virus.”
The virus outbreak was the result of an initial mutation that allowed the virus to transmit from bats, to another animal host and then to humans. Another mutation allowed it to transmit between people
“In its standard form, in its bat coronavirus state, it is not infectious to humans,” Mr. Plante said.
The first U.S. samples were obtained by the Centers for Disease Control and Prevention from a patient in Washington state and to the Texas virus center on Feb. 6.
China’s Wuhan Institute of Virology, after initially agreeing to provide virus samples to the center, declined to supply any, Mr. Plante said.
The center is a central point for sending samples – both infectious and non-infectious virus replicas – and has sent them to more than 100 research and diagnostic centers, mainly in the United States. Researchers worldwide are working to determine how the virus functions, how it spreads and how it infects.
“We already have infectious clones, we already know the receptor,” Mr. Plante said. “There are animals already in place and with laboratories, repositories that are being collaborative, we are getting a lot of work done very quickly.”
The similarities to the earlier SARS virus, which spread to about 8,000 people worldwide and killed almost 800, are still being studied.
By contrast, the new virus has infected more than 586,000 people and caused nearly 27,000 deaths worldwide, according to a Johns Hopkins University tracker.
“Thankfully, the case fatality rate is lower with this virus, though it does seem to be more transmissible,” Mr. Plante said.
Current studies are seeking to determine the how long the virus can live before breaking down, its viability on different surfaces, and its ability to spread through the air.
“The main thing is that we need to better understand how this virus is being transmitted,” Mr. Plante said. “One of the things that might be new is we do have significant reports that asymptomatic people spread this virus, which seems to be a newer trait that was not necessarily proven with the SARS coronavirus the original.”
Asymptomatic spread means the virus can be passed from person to person before symptoms appear. The main symptoms have been high fever and persistent, dry cough.
“And that right there is possibly part of the reason why it is so difficult to control,” he said.
Researchers have not determined the origin of the new coronavirus.
The National Academies of Science, Engineering and Medicine said Bai Chunli, president of the Chinese Academy of Sciences, initially agreed that the Wuhan Institute of Virology would share virus samples with the Texas center. Those samples might have helped researchers learn more about its origins.
After some discussions, that “never actually happened,” Mr. Plante said.
Mr. Plante said China recently has been slightly more forthcoming but tight political controls have limited cooperation.
“Samples … are notoriously difficult to get out of China,” he said, noting its political climate and regulations.
Data sharing among nations outside of China picked up as the virus spread and officials began to understand the severity of the outbreak and need to respond rapidly.
China learned about the virus in early December but failed to take action for weeks to stem the outbreak, which coincided with the lunar new year, a major holiday when millions of Chinese traveled throughout the country and the world.
An estimated 5 million people from Wuhan were part of the holiday exodus that has been blamed for the global spread.
Mr. Plante dismissed a theory about the virus that experts have debated: That the virus was being researched at a laboratory in Wuhan and may have escaped through mishandling of infected animals or through an accidental infection of a lab worker.
“There’s a lot of conspiracy theories that this came out of a biocontainment facility and things of that sort,” he said. “But these viruses are closely related to bats.”
The possibility of the reemergence of the new SARS virus was contemplated during the 2003 outbreak.
“This is a zoologic virus these bat coronaviruses and they basically need to adapt to be able to infect humans and transmit human-to-human,” Mr. Plante said.
“I’ve seen no evidence this is a virus that came out of a lab. This appeared in an area where it was hypothesized to appear. Close contact with animals that have zoonotic virus and people like we’re seeing in these wet markets are prime places for these zoonoses to emerge into human populations.”
Zoonosis is a disease transmitted from animals to humans.