The World Health Organisation has insisted that all available evidence suggests coronavirus was not manufactured in a lab.

Takeshi Kasai, WHO Regional Director for the Western Pacific, said that while it has not been possible to identify the exact source, the disease likely came from animals.

The WHO has previously said that the genetic makeup of the virus is closely related to coronaviruses identified in bats - suggesting the disease originated in that animal before making the leap into humans.

Mr Kasai spoke out after President Trump said the US is looking into whether the virus leaked from a lab near Wuhan which was doing research on coronaviruses including the SARS virus, a close genetic relative of the current coronavirus.

The WHO has insisted that coronavirus likely originated in animals and was not man-made, amid persistent conspiracy theories that it leaked from a lab in Wuhan (pictured)

The WHO has previously said the new coronavirus is similar to viruses already identified in a common species of bat (pictured), making them a likely source

German Chancellor Angela Merkel has also called for 'more transparency' from China over the origin of the virus.

Meanwhile Veronika Skvortsova, Russia's former health minister, refused to rule out the possibility that the virus came from a lab and called for a 'very through study'.

WHO West Asia director Takeshi Kasai spoke out as world leaders called for an investigation into the virus's origins

It is thought that the new coronavirus first made the jump from animals to humans at the Huanan Seafood Market in Wuhan, which is where the earliest cluster of cases was detected.

However, China has so far failed to identify 'patient zero' - the first person to catch the infection.

Without knowing who patient zero is or how they were infected, it will be impossible to know the true source of the virus.

The WHO itself admits that the virus could have been carried to the Huanan Market by an already-infected human, who then spread it to others.

Investigations are currently ongoing into possible cases of coronavirus dating back to mid-November 2019, a month earlier than previously thought.

It came as rare footage emerged showing carrying out research at the Wuhan Institute of Virology - which has found itself at the centre of conspiracy theories around the virus's origin.

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A video released by Chinese state broadcaster CCTV in February shows virologists donning spacesuit-like protective gears as they work in the P4 lab at the Wuhan Institute of Virology

The lab is said to have three testing rooms, two animal storage rooms, one virus bank and one animal-dissection room. Twenty-four scientists can work there at the same time, CCTV said

A video released by Chinese state broadcaster CCTV in February provides a glimpse into the institute.

The £34million lab is affiliated to the Chinese Academy of Sciences. It was completed in 2015 and officially opened in 2018.

In the clip, one researcher, named Zhang Huajun, demonstrates how he and one colleague put on two layers of protective suits and pass five air-tight chambers before entering the core part of the lab.

The lab is said to have three testing rooms, two animal storage rooms, one virus bank and one animal-dissection room. Twenty-four scientists can work there at the same time.

Researcher Zhang said the building was designed in such a way that air can only flow into the lab from the outside, not the other way around, to prevent leaks.

Dr Yuan Zhiming, the deputy head of the Wuhan Institute of Virology, hit back at accusations that the virus leaked from his lab in an interview with state media over the weekend.

'There's no way this virus came from us,' Dr Yuan told CGTN, the English-language arm of CCTV. 'I know it's impossible.'

Dr Yuan Zhiming (pictured), the deputy head of the Wuhan Institute of Virology, told CGTN 'there's no way this virus came from us'. He also refuted claims that the virus was man-made

Dr Yuan said that a man-made coronavirus would be beyond human intelligence as he rejected claims that the virus was artificially engineered.

Wuhan virus lab researchers warned of SARS-like coronavirus outbreaks A lead virologist and her team at a Wuhan lab warned of the possibility of SARS-like coronavirus outbreaks in China 11 months before the novel coronavirus epidemic ravaged the city. The ominous prediction came from a study carried out by Shi Zhengli and her colleagues at the Wuhan Institute of Virology when they stressed the importance of conducting investigations of viruses from bats. Shi, nicknamed the 'Bat Woman', allegedly sequenced the genes of the new coronavirus in three days after the epidemic emerged, but was silenced by her boss. In the article from in January, 2019, Shi and her the team highlighted the likelihood of another coronavirus epidemic in China by analysing three large-scale outbreaks caused by Severe Acute Respiratory Syndrome (SARS), Middle East Respiratory Syndrome (MERS), and Swine Acute Diarrhea Syndrome (SADS) respectively. The article said that all three pathogens were coronaviruses and could be traced back to bats, and two of them had originated in China. The researchers urged: 'Thus, it is highly likely that future SARS- or MERS-like coronavirus outbreaks will originate from bats, and there is an increased probability that this will occur in China. 'Therefore, the investigation of bat coronaviruses becomes an urgent issue for the detection of early warning signs, which in turn minimizes the impact of such future outbreaks in China.' Advertisement

'Some scientists believe that to synthesise a virus requires extraordinary intelligence or workload, so I have never believed that we humans have the capabilities at this time to create such a virus,' he explained.

Dr Yuan attributed the theories to the fact that the institute and the P4 lab are in Wuhan, so 'people can't help but make associations which I think is understandable'.

But he criticised people who 'are deliberately trying to mislead people'. He blamed US senator Tom Cotton and the Washington Post for promoting such claims.

'They have no evidence or knowledge. This is entirely based on speculation,' he denounced.

'Part of the purpose is to confuse people, to interfere with our entire epidemic activities or our scientific activities.'

Although scientists believe that the virus jumped to humans from wild animals sold as food in a market about 10 miles from the lab, conspiracy theorists promote different assumptions.

Some people claim that the virus, formally known as SARS-CoV-2, could be a biological warfare weapon engineered there. Others suspect that it escaped from the lab.

Shi Zhengli, a deputy director at the institute, told the press in February that she 'guaranteed with her own life' that the outbreak was not related to the lab.

The institute also refuted reports which named Huang Yanling, a researcher at the Institute of Virology, as 'patient zero' – the first person to be infected.

'I can tell you for sure that none of our students, retirees or any of our staff has been infected,' Dr Yuan said.

American intelligence services have reportedly launched a full-scale investigation into the lab over claims that scientists there allowed the novel coronavirus to escape as part of a botched experiment, leading to a global pandemic.

Sources said American analysts will present their findings 'in the near term' to Trump, who will then huddle with aides to determine how to hold China accountable for the pandemic

China has denied speculation that the pathogen originated inside the Wuhan Institute of Virology lab, though US government agencies are now said to be piecing together a timeline of what authorities in Beijing knew to 'create an accurate picture of what happened'.

Sources told Fox News on Friday that American analysts will present their findings 'in the near term' to President Trump, who will then huddle with aides to determine how to hold China accountable for the pandemic.

The American intelligence sources told Fox News that analysts in Washington have ruled out the theory that the coronavirus was engineered by Chinese scientists as a bioweapon.

Experts note that the genome mapping of the virus indicates that there were no genetic alterations made to it.

Scientists believe that the virus jumped to humans from wild animals sold as food in a market about 10 miles from the lab, but conspiracy theorists are promoting different assumptions

US sources told Fox News they believe that 'patient zero' became infected with coronavirus as it was being studied inside the lab.

The infected person then is believed to have spread the virus throughout the city and onwards.

While the exact origin of the virus remains unknown, the broad scientific consensus holds that SARS-CoV-2 came from bats.

COVID-19, the disease caused by the new coronavirus, has killed more than 165,000 people and infected over 2.4 million worldwide since the pandemic began in Wuhan last December.

Why did China build a virus lab in Wuhan? A worker is seen inside the P4 laboratory at the Wuhan Institute of Virology in Wuhan on February 23, 2017 Chinese officials decided to build the Wuhan Institute of Virology after the country was ravaged by an outbreak of SARS in 2002 and 2003. SARS, another kind of coronavirus, killed 775 people and infected more than 8,000 globally in an epidemic that lasted about eight months. It took the Chinese 15 years to fully complete the project, which cost a total of 300million yuan (£34million). The French helped design the building. Its crown jewel is a four-storey lab with the highest biosafety level of P4. It's the most advanced laboratory of its type in China. Construction of the lab was finished in 2015 and it officially opened on January 5, 2018, after passing various safety inspections. Describing the significance of the P4 lab, China Youth Online billed it as the 'aircraft carrier of China's virology'. The state-run newspaper said it 'is capable of researching the deadliest pathogens'. One researcher, Zhou Peng, told state news agency Xinhua in 2018: 'We are proud to say that we are already at the forefront in the field of studying the immunity mechanism of bats, which carry viruses for a long time. 'Bats carry viruses but are not infected [by them]. [They] provide hope for mankind to study how to fight viruses.' Advertisement

How the man running World Health Organisation trashed by Trump as China-centric is a career politician who worked for a Communist junta and became WHO's first NON-doctor Director-General 'following intense lobbying from Beijing'

Tedros Adhanom Ghebreyesus, a little-known figure before the coronavirus pandemic, has risen to prominence as Director-General of the World Health Organisation which is spearheading global responses to the virus.

Dr Tedros - who has never practised as a medical doctor - is a career politician who was born in what is now Eritrea, began work under the Communist Derg junta, came to study in the UK, then rose to the top of Ethiopia's government first as Health Minister and then Foreign Minister before being elected to lead the WHO in 2017.

He is now facing heavy criticism over his handling of the pandemic, especially for praise he heaped on China's communist party for its response - hailing the regime's 'commitment to transparency' and saying the speed with which it detected the virus was 'beyond words'.

That has led to allegations - including by Donald Trump - that the WHO is 'China-centric', a position that the US President has promised to 'look into'.

Trump has said the US will suspend funding to the WHO until an investigation has been carried out, while suggesting that they withheld information on the virus.

Indeed, it is not the first time that Dr Tedros has been accused of cosying up to China. Shortly after his election victory in 2017, it was alleged that Chinese diplomats had been heavily involved in lobbying for him.

UN records also show that Chinese contributions to both Ethiopia's aid budget and the WHO have substantially increased during times when he was in top leadership positions.

The WHO and its Director-General Tedros Ghebreyesus (left, pictured meeting with Xi Jinping in January) has faced accusations that the organisation is 'China-centric' and has been too quick to praise the regime's coronavirus response

Shortly after his election to the WHO, a report in The Times said: 'Chinese diplomats had campaigned hard for the Ethiopian, using Beijing’s financial clout and opaque aid budget to build support for him among developing countries.'

Dr Tedros - who is married and has five children - was born in 1965 in Asmara, which was part of Ethiopia at the time but is now in Eritrea.

As a child he saw his younger brother die to an infection, which he believes was measles, which he later said spurred his determination to work on health and health policy.

He graduated from university in Ethiopia in 1986 with a degree in biology and went to work as a health official in the regime of Marxist dictator Mengistu Haile Mariam, while the country was ruled by the Derg military junta.

According to the BBC, Dr Tedros then joined the hard-left TPLF - which started life as a Communist party and played a major role in overthrowing Mariam in 1991. It later became part of the EPRDF, a coalition of left-wing parties that ruled Ethiopia until last year.

Around the same time as Mariam's ouster, Dr Tedros left Ethiopia and came to the UK where he studied at the London School of Hygiene & Tropical Medicine, graduating with Masters of Science in Immunology of Infectious Diseases in 1992.

He then went on to study at the University of Nottingham, where he received a PhD in community health in 2000.

After this, he returned to Ethiopia where he joined the health ministry and rose through the ranks from regional health minister all the way to national Minister for Heath - a position he took up in 2005.

Before ascending to the top ranks of the WHO, Dr Tedros studied in the UK and served Ethiopia's ruling left-wing coalition as health minister and then as foreign minister (pictured in the role in 2015)

During his tenure, which lasted until 2012, he was widely praised for opening thousands of health centres, employing tens of thousands of medics, bringing down rates of HIV/AIDS, measles and malaria, as well as bringing information technology and the internet into the heath system.

In November 2012 he was promoted to Foreign Minister, and was widely hailed for helping to negotiate a boost in UN funding for Ethiopia, including as part of the Addis Ababa Action Agenda.

Indeed, UN funding records show that around this time the country received millions in additional funding - including from China, which had previously given little or nothing to support the country.

In 2015 and 2016 China gave some $16million to Ethiopia in spending commitments and cash contributions, largely in support of food or refugee programmes.

In 2011, just before Dr Tedros took up the role, and in 2017, just after he left, China handed over another $44million in commitments and contributions.

Its total contributions outside of this period, dating back to the year 2000, were just $345,000.

In 2017, Dr Tedros left the Ethiopian government and entered the running for Director-General of the WHO as the tenure of Dr Margaret Chan, a Canadian-Chinese physician, was coming to an end.

The election was the first to take place under a system of polling all UN member states as part of a secret ballot. Previously, leaders were chosen by a closed-door vote of an executive committee.

Eventually the field was boiled down to two candidates - Dr Tedros and Briton Dr David Nabarro, a life-long physician who had helped lead UN responses to previous outbreaks including bird flu, the cholera outbreak in Haiti, and the Ebola outbreak in West Africa.

Dr Tedros (pictured with his family) was widely praised during his tenure as Ethiopia's health minister for helping to lower rates of measles, malaria, and HIV/AIDS as well as building thousands of health centres and hiring thousands of medics

Dr Tedros won the ballot by a reported 133 votes to 50, becoming the first African leader of the WHO and the first non-medic to hold the role. His victory came in part thanks to 50 out of 54 African states voting for him.

However, he quickly mired himself in controversy by recommending African dictator Robert Mugabe as a WHO Goodwill Ambassador, amid allegations he trying to repay favours granted during the election.

There were reports that the move was also intended to reward China, a long-time supporter of Mugabe, for using its influence to have him elected.

The Times added: 'China has praised the authoritarian development model of Ethiopia’s regime, which rules under emergency powers and has put down pro-democracy protests.'

During the 2017 election itself, several groups within Ethiopia opposed Dr Tedros's appointment due to his links with the TPLF and allegations that they stifled journalists and repressed minorities.

Dr Tedros was also accused of covering up three separate cholera outbreaks in 2006, 2008 and 2011 by mis-reporting it as 'watery diarrhea', allegations he dismissed as a 'smear campaign' by his British rival.

Following his election to the WHO, Dr Tedros vowed to reform the organisation by placing an emphasis on universal healthcare at its centre while also increasing funding.

Further UN funding records show that, during his tenure, assessed contributions to the WHO by China have also risen significantly - from roughly $23million in 2016 to $38million in 2019.

China has also committed to a further $57million in funding in 2020, though has yet to pay the balance.