Ancestor of Covid virus was lurking in animals for MILLIONS of years before it m

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The ancestor of the coronavirus could have been lurking in animals for millions of years before it jumped to humans, a virologist has claimed.

The coronavirus, known scientifically as SARS-CoV-2, became able to infect humans when it mutated while inside an animal and then jumped across species.

This happened for the first time last year in China and the virus – which turned out to be both fast-spreading and deadly to humans – has since infected at least 110million people and killed 2.4million.

Dr Emilia Skirmuntt, an evolutionary virologist at the University of Oxford, is studying viruses that affect bats and said it was likely they carried a version of the virus for a long time.

Scientists believe that bats passed the virus to another species which then gave it to humans, but Dr Skirmuntt suggested it could have skipped over the intermediary.

What 'species zero' was, she told MailOnline, was still unclear. And scientists would probably never pinpoint the exact moment the virus spread from animals to people.

Experts had suggested pangolins could have transmitted the virus to humans, but Dr Skirmuntt said this was unlikely because it appeared to make them sick, too, meaning they wouldn't be efficient 'reservoirs' to incubate the virus.

The origin of the pandemic is still hazy and China has been accused of covering up the true extent of the outbreak and of failing to hand over key data to a World Health Organization team last month.


Dr Skirmuntt told MailOnline: 'The virus needed to mutate to be able to jump to humans.

'The ancestor of this coronavirus was an animal species which were reservoirs for millions of years and then there was some mutations which made it more efficient with infecting other species and humans. That’s how we got SARS-CoV-2.'

She disputed the theory that pangolins might have been the intermediate species between bats and humans.

Bats are known to incubate viruses that are relatively harmless to them but can be dangerous to people or other animals, such as the Nipah virus.

'With pangolins we have seen similar coronaviruses,' she said.

'The problem is the coronaviruses we have seen in them, made them sick and that shouldn’t happen with reservoir species.

'The long term co-evolution makes the pathogen show more symptoms upon infection.

'Only one protein of coronavirus seen in pangolins is more than 90 per cent similar to SARS-CoV-2, and it should be a bigger proportion to really say that is the intermediate species.'


Dr Skirmuntt added: 'It might have been also just a bat which jumped from bat to human. It’s very hard to say with no samples available from all of these animals.'

She said when other coronaviruses — different to the one that causes Covid — have infected humans previously, they had arrived via an intermediate species.

Scientists suspect the same route was traveled by SARS-CoV-2 but it is hard to be sure because the beginning of the pandemic is poorly documented.

World Health Organization microbiologist Dominic Dwyer, who was part of the investigative team sent to China, said authorities in the country had refused to hand over data from early cases in the pandemic.

The WHO asked for details on the first 174 cases detected in Wuhan in early December 2019, half of which were connected to the seafood market, but were only handed a summary.

'That's why we've persisted to ask for that,' Professor Dwyer said. 'Why that doesn't happen, I couldn't comment.

'Whether it's political or time or it's difficult... But whether there are any other reasons why the data isn't available, I don't know. One would only speculate.'

And the importance of animals in the spread of disease continues to be investigated, with a study published in the journal Nature Communications this week suggesting that the next pandemic could come from hedgehogs.

UK researchers used machine learning to predict associations between 411 strains of coronavirus and 876 potential mammal host species.

Their model 'implicated' the common hedgehog, the European rabbit and the domestic cat as possible hosts for new coronaviruses.

It also highlighted the lesser Asiatic yellow bat as a possible source, which is already known to host coronaviruses that are common in East Asia.

The University of Liverpool team said in their paper: 'Our results demonstrate the large under-appreciation of the potential scale of novel coronavirus generation in wild and domesticated animal.

'These hosts represent new targets for surveillance of novel human pathogenic coronaviruses.'

They said the emergence of new strains is an 'immediate threat to public health'.

There may be more than 30 times more host species for coronaviruses than currently known, they say, which could all potentially harbour new strains of Covid-19.

In addition, they estimate that there are over 40 times more mammal species with four or more coronavirus strains than has previously been observed.

Some mammals identified in the study as potential hosts for new coronavirus strains – like horseshoe bats, palm civets and pangolins – have already been linked to either SARS-CoV-1, which caused the 2003 SARS outbreak, or SARS-CoV-2, which causes Covid-19.  

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