Another monkey virus in Cell could spread to humans

According to a new study published online in the journal Cell on Sept.
30 at the University of Colorado Boulder, an unknown family of viruses already circulating in wild African primates known to cause deadly Ebola-like symptoms in some monkeys is "preparing to spill" to humans
.
While the arteritis virus has been considered a serious threat to macaques, no human infections have been reported
to date.
It's uncertain what effects
the virus would have on humans if it crossed species.
But the authors have compared it to HIV (which originated in the African monkey SIV), calling for vigilance: They say that by now observing the arteritis virus in animals and humans, it is possible for the global health community to avoid another pandemic
.

"This animal virus already knows how to enter human cells, multiply itself, and escape some important immune mechanisms that we thought would protect us from animal viruses
.
" This is very rare," said
Sara L.
Sawyer, senior author and professor of molecular, cell and developmental biology at the University of Colorado Boulder.
"We should pay attention to
this.
"

There are thousands of unique viruses circulating in animals around the world, most of which do not cause any symptoms
.
In recent decades, more and more viruses have infected humans, wreaking havoc on naïve immune systems that have no experience defending up: including Middle East Respiratory Syndrome (MERS) in 2012, severe acute respiratory syndrome coronavirus (SARS-CoV) in 2003, and SARS-CoV-2 (the virus that causes COVID-19)
in 2020.

For 15 years, Sawyer's lab has been using laboratory technology and tissue samples from wildlife around the globe to explore which animal viruses may be susceptible to transmission to humans
.

In the latest study, she and Cody Warren, then a postdoctoral fellow at the University of California's Institute for Frontiers in Biology, focused their attention on the arteritis virus, which is common in pigs and horses but understudied
in non-human primates.
They specifically studied the monkey hemorrhagic fever virus (SHFV), a virus that causes a deadly disease similar to the Ebola virus, which caused deadly outbreaks
in captive macaque populations as early as the 1960s.

The study showed that a molecule or receptor called CD163 plays a key role in the biology of the monkey arteritis virus, enabling the virus to invade and cause infection
of target cells.
Through a series of laboratory experiments, the researchers were surprised to find that the virus is also very good at attaching to the human version of CD163, entering human cells and quickly replicating itself
.

Like the human immunodeficiency virus (HIV) and its precursor, the monkey immunodeficiency virus (SIV), the monkey arteritis virus appears to attack immune cells, invading key defense mechanisms and occupying them
in the body for long periods of time.

Warren, now an assistant professor at Ohio State University's College of Veterinary Medicine, said: "There are deep similarities
between this virus and the ape virus that causes the HIV epidemic.
" The authors stress that another pandemic will not happen right away and that the public need not panic
.
But they do recommend that the global health community prioritize further research into monkey arteritis viruses, develop blood antibody tests for them, and consider monitoring
people in close contact with animal carriers.
Many African monkeys already carry a high viral load of multiple arteritis viruses and are usually asymptomatic, and some species often interact with humans and are known to bite and scratch people
.

"Just because we haven't diagnosed a human arteritis virus infection doesn't mean no one has been in contact with it
.
We haven't looked for it
yet.
"After all, in the 1970s, no one had heard of HIV
.
And now researchers know that HIV may have originated in SIVs, which infected non-human primates in Africa, and was likely transmitted to humans
sometime in the early 20th century.
In the 1980s, when it began killing young men in the United States, there were no serological tests and no treatment
.

Sawyer said there is no guarantee that these monkey arteritis viruses will be transmitted to humans
.
But one thing is certain: more viruses can spread to humans and cause disease
.
"COVID is just the latest in a long string of spillover events from animals to humans, some of which have erupted into global disasters
.
Our hope is that by raising awareness of the virus we should be aware of, we can get ahead of that, so that if human infections start to happen, we can act
quickly.
”

Cody J.
Warren, Shuiqing Yu, Douglas K.
Peters, Arturo Barbachano-Guerrero, Qing Yang, Bridget L.
Burris, Gabriella Worwa, I-Chueh Huang, Gregory K.
Wilkerson, Tony L.
Goldberg, Jens H.
Kuhn, Sara L.
Sawyer.
Primate hemorrhagic fever-causing arteriviruses are poised for spillover to humans.
Cell, 2022