A Covid-like virus found lurking in bats in southern China is one of five viruses that can infect humans.
The virus, known as BtSY2, is closely related to SARS-CoV-2, the virus that causes Covid, and is “at particularly high risk of emergence”.
It is one of five “viruses of concern” found in bats in China’s Yunnan province that are “likely to be pathogenic to humans and livestock,” scientists said.
The team warns of a potential new “zoonotic disease,” a disease caused by a pathogen that is transmitted to humans from other animals.
A Covid-like virus found lurking in bats in southern China is one of five viruses that can infect humans. Evidence already suggests that SARS-CoV-2 originated in horseshoe crabs (pictured)
What is a zoonotic disease?
Zoonotic diseases can be transmitted from one species to another.
Infectious agents, called pathogens of these diseases, can survive across species boundaries.
They range in potency, and one species is often less dangerous than another.
To be successful, they rely on long-term and direct contact with a variety of animals.
A common example is strains of influenza adapted to survive in humans in a variety of different host animals.
The study was led by researchers from Zhongshan University in Shenzhen, the Yunnan Institute for Endemic Disease Control, and the University of Sydney.
It is detailed in a new, as-yet-unpeer-reviewed study published as a preprint paper. Bio Rxiv server.
“We identified five viral species that are likely to be pathogenic to humans or livestock, including a novel recombinant SARS-like coronavirus that is closely related to both SARS-CoV-2 and 50 SARS-CoV. identified,” the team said in their paper.
“Our study highlights the common occurrence of bat virus interspecific transmission and co-infection and its impact on virus emergence.”
For this study, researchers collected rectal samples from 149 individual bats representing 15 species in six counties or cities in Yunnan, China.
RNA – the nucleic acid present in living cells – was extracted and sequenced individually for each bat.
Worryingly, researchers noted the high frequency of multiple viruses infecting one bat at a time.
According to Professor Jonathan Ball, a virologist at the University of Nottingham, this could lead to existing viruses swapping parts of their genetic code. This is a process known as recombination and forms new pathogens.
“An important lesson is that individual bats can harbor a wide variety of virus species, and sometimes host them simultaneously,” said Ball, who was not involved in the study. Told. Telegraph.
Overview of the samples analyzed in this study. (A) Locations in Yunnan, China, where bat samples were collected. Pie charts show the composition of bat species sampled at each location, with the total area of the pie chart proportional to the number of individuals captured. Colors indicate different bat species (B)
A bat virus known as BtSY2 is closely related to SARS-CoV-2, the virus that causes Covid (depicted artistically). The team does not speculate about the origin of SARS-CoV-2, which is related to the SARS-CoV-1 virus that caused the 2002-2004 SARS outbreak.
“Such co-infections, especially with related viruses, such as coronaviruses, give the viruses the opportunity to exchange important pieces of genetic information, naturally giving rise to new subspecies,” he said.
BtSY2 also has a SARS-CoV-2-like receptor-binding domain that is an important part of the spike protein used to latch onto cells in human cells.
BtSY2 also has a ‘receptor binding domain’ (a key part of the spike protein used to latch onto cells in human cells), which is similar to SARS-CoV-2 and allows the virus to survive in humans. This suggests that it is possible to infect
‘BtSY2 may be available [the] human ACE2 receptor for cell entry,” the team added.
ACE2 is a receptor on the surface of human cells that binds to SARS-CoV-2 and allows SARS-CoV-2 entry and infection.
Yunnan province in southwestern China has already been identified as a hotspot for bat species and bat-borne viruses.
A number of pathogenic viruses have been detected there, including close relatives of SARS-CoV-2 such as the bat viruses RaTG1313 and RpYN0614.
The team does not speculate about the origin of SARS-CoV-2, which is related to the SARS-CoV-1 virus that caused the 2002-2004 SARS outbreak.
Evidence has already suggested that SARS-CoV-2 originated in horseshoe crabs, but the virus may have been transmitted to humans via pangolins.
SARS-CoV-2 likely originated in bat species, but may have reached humans via intermediate species such as pangolins, scaly mammals often confused with reptiles (picture). ).
Similarly, bats are believed to have caused the deadly Ebola virus outbreak in West Africa from 2013 to 2016.
Yunnan, an area identified by the new study, is home to pangolins, which are consumed as food in China and used in traditional medicine.
According to a 2021 study in the journal Comprehensive Environmental Sciencethe virus may have jumped from bats to Sunda pangolins and masked palm citizens in Yunnan province.
They were then captured and transported over 1,200 miles to a wildlife market in Wuhan, where the first Covid outbreak occurred.
SARS was first identified in China in 2002
Severe acute respiratory syndrome is caused by the SARS coronavirus known as SARS CoV.
Coronaviruses commonly infect both humans and animals.
There have been two outbreaks of highly contagious and potentially life-threatening pneumonia.
Both occurred between 2002 and 2004. Since 2004, no known cases of SARS have been reported anywhere in the world.
The World Health Organization (WHO) continues to monitor unusual disease activity in countries around the world.
where did it originate?
in China in 2002. It is believed that a strain of the coronavirus, normally found only in small mammals, mutated and became capable of infecting humans.
The SARS infection spread rapidly from China to other Asian countries. There have also been small numbers of cases in several other countries, including four in the UK, and a large outbreak in Toronto, Canada.
The SARS pandemic was finally brought under control in July 2003 following a policy of isolating suspected infected persons and screening all passengers traveling by air from infected countries for signs of infection. He was taken.
During the period of infection, there were 8,098 reported cases of SARS and 775 deaths. This means that one of her 10 infected with the virus has died.
People over the age of 65 are particularly at risk, with more than half of the people who died from infection in this age group.
In 2004, there was another small SARS outbreak associated with a medical laboratory in China.
It was thought to be the result of someone having direct contact with a sample of the SARS virus, rather than animal-to-human or human-to-human transmission.
how does it spread?
Small droplets of saliva airborne when an infected person coughs or sneezes. If someone else inhales the droplets, they can become infected.
SARS can also be spread indirectly when an infected person touches surfaces such as door handles with unwashed hands.
People who touch the same surfaces can also become infected. The virus can also be spread through the faeces of an infected person.
For example, if you don’t wash your hands properly after going to the bathroom, you can pass the infection on to others.
Symptoms of SARS
SARS usually has flu-like symptoms that begin 2 to 7 days after infection. In some cases, the time between exposure to the virus and the onset of symptoms (the incubation period) can be up to 10 days.
Symptoms of SARS include:
- high fever (fever)
- Exhaustion (fatigue)
- muscle pain
- loss of appetite
After these symptoms, the infection begins to affect the lungs and airways (respiratory system), causing additional symptoms such as:
- dry cough
- difficulty breathing
- Increased lack of oxygen in the blood, which can be fatal in the most severe cases
Treatment of SARS
There is currently no cure for SARS, but research is underway to find a vaccine.
Persons suspected of having SARS should be hospitalized immediately and quarantined under close observation.
Treatment is primarily supportive and may include the following:
- Assisting breathing with a ventilator that supplies oxygen
- antibiotics to treat bacteria that cause pneumonia
- antiviral drug
- high-dose steroids to reduce swelling in the lungs
There is not much scientific evidence that these treatments work. The antiviral drug ribavirin is known to be ineffective in treating SARS.