A new survey of the world's leading scientists studying diseases in humans has found the next global pandemic, which could kill millions, could be an infection that humans have never been exposed to before.

       Dubbed Disease X, it is the terrifying pathogen expected to emerge at some time in the future once again, leaving the UK and other nations languishing in lockdown measures.

       The Mail Online reports a study by the Abbott Pandemic Defence Coalition found global deaths could be caused by a virus that is "highly transmissible" and for which there are "no tests, treatments or vaccines."

       The World Health Organisation (WHO) has compiled a list of a top 30 infectious threats that humanity already faces, but in a report from 200 scientists it was concluded "Disease X" could be a virus already known to science, but which suddenly changes and accelerates in danger level at an alarming rate.

       Covid-19, the virus which caused the recent worldwide pandemic, was an infection known to occur in animals studied by scientists at labs in Wuhan, China. But once the disease spread to humans, it took on a whole new level of danger with lethal results for millions.

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       Dr Ana Maria Henao-Restrepo, from the World Health Organisation (WHO), said Disease X was not here yet, but scientists were preparing for it in the future.

       During a WHO Q&A session, Dr Maria Henao-Restrepo added: "We are preparing for the future. So we are talking about a hypothetical disease and to give a name the scientists call it Disease X to prepare for the hypothetical virus or bacteria that in the future can cause large outbreaks or epidemics or pandemics.

       "There are many viruses and bacteria that can infect animals, including humans. For a few we already have vaccines, diagnostics and therapeutics.

       "We know what are the viruses that we need to be alert to, we know what are the bacteria we need to be alert to, but there are many thousands of them. So we need to have a simplified way to refer to them without knowing which one will cause the next pandemic. And we call it Pathogen X."

       In the UK, Professor Garrett Wallace Brown, chair of Global Health Policy at the University of Leeds, was part of the country's response to the Covid-19 pandemic.

       He told the Mail Online: "I know how under-prepared we were. Cabinet made big decisions that seemed politically expedient but were not scientifically sound. I don't think we've learned from that. If another pandemic comes along, we will probably do another set of knee-jerk responses such as lockdowns which may not be necessary."

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       Professor Adam Kucharski, co-director of the Centre for Epidemic Preparedness and Response at the London School of Hygiene and Tropical Medicine, said Britain could learn from other countries.

       He added: "Asian countries such as Japan used their infection-testing technology effectively so that they could identify people transmitting Covid, then track the virus's spread, institute local restrictions and ramp up vaccinations.

       "They had more freedom but fewer cases and morbidity than us."

       A spokeswoman for the Department of Health and Social Care told Good Health: "Together with the UK Health Security Agency, the Government is ensuring we’re prepared and ready to respond to any current and future health threats.

       "Since the Covid-19 pandemic, stockpiles of PPE for pandemic preparedness have been replenished and include some excess stock originally obtained for the pandemic response."