A virus spreads among different species of monkeys. It triggers what is known as hemorrhagic fever and kills many animals. Researchers are examining the pathogen more closely and are emphatically warning of a possible further development.

A virus that can cause serious illness in monkeys is also able to enter human cells and multiply there. That’s what a research team from the University of Colorado found. This is the so-called Simian Hemorrhagic Fever Virus, or SHFV for short, which was found a few decades ago, mainly in rhesus monkeys and pasque monkeys in Africa. The pathogen, which belongs to the RNA viruses and is assigned to the so-called delta arteriviruses, can, like the Ebola pathogen, trigger a severe hemorrhagic fever in the animals and lead to death.

However, infections with SHF viruses have now been detected not only in the monkeys, but also in primates such as gorillas, chimpanzees and macaques in various primate stations. That was the reason for the research team led by Sara Sawyer and Cody Warren to examine the pathogen and its properties more closely. The researchers found that the mechanism by which SHFV penetrates cells is very similar to that of Ebola, Lassa and other pathogens that can also cause dangerous hemorrhagic fevers.

In cell tests in the laboratory, the SHF virus used a specific receptor as an intracellular docking site. This site, named the CD163 receptor, is found in cells of monkeys, apes and humans. According to the researchers, the CD163 receptor plays a key role in the spread of simian arteriviruses. It also allows the viruses to bind to the CD163 receptors in human cells, enter them, and make copies of themselves there relatively quickly. “This animal virus has figured out how to gain access to human cells, replicate there, and even evade some of the important immune mechanisms that are supposed to protect us from such an animal virus. This is quite rare,” Sawyer said in a statement from the university quoted.

In addition to the researchers’ finding that the SHF virus meets all the necessary requirements for infecting humans, there is another one: Like the HI virus and its precursor, monkey arteriviruses also appear to attack immune cells, deactivate important defense mechanisms and remain in the body over the long term to be able to “The similarities between this virus and the simian viruses that caused the HIV pandemic are profound,” explains Warren.

Although no infection with SHFV in humans is known to date, the research team does not rule out an infection. “We weren’t looking for it,” Warren said. Even if the researchers of the study do not want to spread fear at the moment, nor can they say with certainty how the pathogen under investigation could actually affect people, they urge caution.

They therefore suggest prioritizing further study of simian arteriviruses, developing blood antibody tests for them, and testing people in close contact with animals who carry these pathogens. This is the only way to act quickly when infections occur in humans. Because one thing is certain: in the future, more viruses will spread to humans and cause diseases. The Covid-19 pandemic is just the latest example of numerous animal-to-human spillover events, some of which have led to global catastrophes, Sawyer said. The results of the study were published in the specialist journal “Cell”.

(This article was first published on Tuesday, October 04, 2022.)