Second strain of coronavirus causing pigs to vomit in China ‘could spread to humans’
Humans could catch another coronavirus strain that has been causing pigs to have severe diarrhoea and vomiting in China.
Swine acute diarrhoea syndrome coronavirus – known as SADS-CoV – is thought to have come from bats and has been threatening the livestock industry since 2016.
A widespread outbreak of the virus, which poses greatest risk to piglets, could have a devastating effect on economies that rely on pork production and sales.
In 2019, America was the world’s third largest producer of pork and a spread of SADS-CoV would be the biggest to hit the industry since 2012’s swine flu.
Researchers from North Carolina have now shown that SADS-CoV can infect and replicate itself within the human airway, liver and intestinal cells.
SADS-CoV belongs to the same family of viruses as SARS-CoV-2 – the agent behind the COVID-19 pandemic.
SADS-CoV which has so far only spread between pigs, is an “alphacoronavirus” compared to SARS-CoV-2 which is a “betacoronavirus”.
Paper author and epidemiologist Ralph Baric of the University of North Carolina at Chapel Hill said: “Many investigators focus on the emergent potential of the betacoronaviruses like SARS and MERS.
“Actually the alphacoronaviruses may prove equally prominent – if not greater – concerns to human health, given their potential to rapidly jump between species.’
The researchers also explained that SADS-CoV is distinct from two common cold alphacoronaviruses in humans, HCoV-229E and HCoV-NL63.
In their study, Professor Baric and colleagues investigated the risk of so-called ‘spillover’ — that SADS-CoV could jump from pigs and infect human population, reports MailOnline.
To do this, they infected various types of synthetic cell with the swine coronavirus and monitored how the virus replicated and spread.
The researchers found that a wide range of mammalian cells — including primary human lung and intestinal cells — are susceptible to SADS-CoV infection.
The team discovered that unlike SARS-CoV-2, swine coronavirus is capable of replicating faster in intestinal cells, rather than in the lungs.
So as far as SADS-CoV is concerned, humans do not have the cross-protective herd immunity that can prevent us from contracting coronaviruses from animal populations.
Paper author and public health expert Caitlin Edwards, also of the University of North Carolina, said: “SADS-CoV is derived from bat coronaviruses called HKU2, which is a heterogenous group of viruses with a worldwide distribution.
“It is impossible to predict if this virus, or a closely related HKU2 bat strain, could emerge and infect human populations.
“However, the broad host range of SADS-CoV, coupled with an ability to replicate in primary human lung and enteric cells, demonstrates potential risk for future emergence events in human and animal populations.”
Courtesy of dailystar.co.uk