A virus similar to COVID (SARS-CoV-2) and recently discovered in Russian bats has been shown to be immune to current vaccines and can spread to humans. virus, named Khosta-2, It is capable of infecting human cells and is resistant to both monoclonal antibodies and serum from people who have been vaccinated against the coronavirus.
This discovery has been made by a team of researchers from the Allen School of Global Health at the University of Washington (USA). The virus belongs to the subcategory of coronavirus similar to SARS-CoV-2 and presents “Disturbing Features”According to the new study published in the journal ‘PLOS Pathogens,’ according to the study.
“Our research further demonstrates that sarbecoviruses circulating in wildlife outside Asia – in places such as western Russia, where Khosta-2 virus was found – also Threatening global health and vaccination campaigns against SARS-CoV-2,” says Michael Letko, a virologist at WSU and the study’s corresponding author.
Khosta-1 and Khosta-2 viruses were discovered in Russian bats in late 2020
a universal vaccine
Letko explains that the discovery of Khosta-2 sheds light The need to develop universal vaccines Those that protect against sarbecoviruses in general, not just the known types of SARS-CoV-2.
“Right now, there are groups trying to come up with a vaccine that not only protects against the next version of SARS-2, but also Protect against sarbecoviruses in general Remember Letko. Unfortunately, many of our current vaccines are designed for specific viruses that we know infect human cells or that pose the greatest risk of infecting us. But this is a constantly changing list. We need to enhance the design of these vaccines to protect against all sarbecoviruses.”
Although hundreds of sarbecoviruses have been discovered in recent years, most are not capable of infecting human cells, mostly in Asian bats. Khosta-1 and Khosta-2 viruses were discovered in Russian bats in late 2020And initially it seemed that they did not pose a threat to humans.
“Genetically, these strange Russian viruses were similar to others discovered in other parts of the world, but since they didn’t resemble SARS-CoV-2, no one thought they were really much to be excited about. for anything,” Letko said. study more We were very surprised to learn that they can infect human cells. This changes our understanding of these viruses a bit, where they come from and which areas are of concern.”
can infect human cells
Letko teamed up with a pair of WSU professors, viral ecologist Stephanie Seifert and viral immunologist Bonnie Gunn, to study the two newly discovered viruses. They determined that Khosta-1 posed a low risk to humans, but Khosta-2 showed some worrying features.
The team found that, like SARS-CoV-2, Khosta-2 can use their spike proteins to infect cells by binding to receptor proteins, called angiotensin converting enzyme 2 (ACE2), which is found in all human cells. They then set out to determine whether existing vaccines protect against the new virus.
Vaccinated against COVID-19 using serum from human population, The team found that Khosta-2 was not neutralized by existing vaccines. They also tested the serum of people infected with the Omicron type, but the antibodies were also ineffective.
Fortunately, Letko explains that the new virus lacks some of the genes thought to be involved in pathogenesis in humans. Even then, There is a risk that Khosta-2 will be reinfected with other viruses such as SARS-CoV-2.
“When we see that SARS-2 has the potential to spread from humans to wildlife, and then other viruses like Khosta-2 are waiting in animals with these properties that we don’t really want them to have, it sets in. is scenario one where you keep rolling the dice until they combine to form a potentially risky virus,” Letko says.