Scientists from the University of North Carolina at Chapel Hill (USA) have demonstrated in laboratory tests that the SADS-CoV coronavirus strain discovered in China, which causes acute diarrhea syndrome in pigs, can be dangerous for humans. SADS-CoV was first transmitted from bats to a herd of pigs in 2016 and has since spread throughout the country.
SADS-CoV has the potential to spread between animals and humans, according to a study published in the journal Proceedings of the National Academy of Sciences (PNAS). So far, scientists have tested the assumption only in laboratories. No specific human cases of SADS-CoV infection are known to date, however, according to a professor in the Department of Epidemiology at UNC-Chapel Hill Gillings School of Global Public Health Ralph Barrikov"Alpha coronaviruses could prove to be just as significant, if not more serious, to human health, given their ability to rapidly transition between species."
What is known about the SADS-CoV coronavirus?
SADS-CoV is classified as an alpha coronavirus, in contrast to the beta coronavirus SARS-CoV-2, which causes COVID-19 in humans. The virus was first discovered in 2004 in bats. The first clinical signs of SADS-CoV-associated viral disease in pigs were observed at the end of December 2016.
According to scientists, this genus of single-stranded RNA viruses can infect both humans and other mammals. In pigs, it causes severe diarrhea and vomiting. The infection spreads quickly in the intestines, unlike SARS-CoV-2, which primarily infects lung cells. In animals, the virus is found in the mucous membrane of the gastrointestinal tract, as well as in the parenchymal organs (liver, spleen, endocrine and exocrine glands).
In the external environment, the virus quickly loses its virulence (the ability to cause disease or death of the body). At t 50-60 ° C, it loses pathogenicity within one hour, at t 80-100 ° C - within 5 minutes, and at t 28 ° C it remains virulent for up to 3 years.
The virus is resistant to antibiotics. American experts have tested the effect on SADS-CoV of the drug remdesivir, which is now used in the treatment of COVID-19. Researchers believe that an antiviral drug could potentially help with this infection. Preliminary results have shown that remdesivir has persistent activity against SADS-CoV, but additional tests in cell and animal cultures are needed to confirm these results.
Why is SADS-CoV dangerous for humans?
Viruses of three genera of coronavirus are dangerous for humans: alpha coronavirus, beta coronavirus and torovirus. The most dangerous coronaviruses belong to the beta coronavirus genus. After testing several types of human cells and infecting them with a synthetic form of "porcine" coronavirus, scientists have found that a fairly wide range of human cells are vulnerable to infection. According to the researchers, the virus is able to spread its genetic material in the cells of the human liver, intestines and respiratory tract.
Scientists hope that cross-protective herd immunity will prevent humans from contracting this virus, since animals are infected in the first place. However, as the study showed, a stable immunity to this type of disease in humans has not yet been developed.