UK health chiefs have issued a stark warning about 24 deadly viruses that could trigger the next ‘Disease X’ – a term often used to describe the culprit behind the next pandemic. 

The UK Health Security Agency (UKHSA) has narrowed the deadliest diseases down to four pathogens currently circulating – including a measles-like virus that could be ‘considerably more dangerous than Covid’.

A leading scientist has warned the list includes viruses that may be ‘impossible to control by even the strictest lockdown’.

Such is the concern that the Government announced the launch of a reference document that will be constantly updated, to keep scientists and researchers up to date with the latest threats. 

One alarming pathogen is that of the Picornaviridae family, which triggers polio-like diseases. 

An example is a virus called acute flaccid myelitis (AFM), a rare condition which causes muscle weakness and paralysis.

A 15-year-old boy from Rochdale was left paralysed in January after contracting AFM, the BBC reported. 

Health chiefs have also warned that viruses of the Paramyxoviridae family may also have pandemic potential. 

UK Health Security Agency (UKHSA) data shows there were 1,603 suspected measles cases in England and Wales in 2023. The figure is more than twice as high as the 735 logged in 2022 and an almost five-fold rise compared to the 360 cases reported in 2021

These include measles, mumps and some respiratory tract infections, as well as the Nipah virus – which can spread from bats or pigs to humans – and causes brain swelling and death. 

Large measles outbreaks have already been reported around the world as vaccination rates decline.    

Last year, 2,911 measles cases were confirmed in England – the highest number recorded since 2012. 

Complications of the deadly illness, which mostly affects children, can include pneumonia, eye inflammation and vision loss as well as brain inflammation, leading to seizures, hearing loss and brain damage.

Other viruses that are ‘on watch’ by officials include coronaviruses such as Covid-19 and MERS, which has so far killed more than 900 – mostly in the Middle East.

Also, alarming is the threat of bird flu – part of the Orthomyxoviridae family of pathogens. 

The virus, which jumps between species, has already been detected in one British farmer who is known to have had contact with infected birds.

Meanwhile, the disease claimed its first human victim in the US in January, killing a 65-year-old with underlying health conditions who was exposed to wild birds.

Bird flu was detected in a sheep in northern England yesterday – the first known case of its kind in the world.

2018: Congolese officials and the World Health Organization officials wear protective suits as they participate in a training against the Ebola virus near the town of Beni in North Kivu province of the Democratic Republic of Congo 

Mark Woolhouse, professor of infectious diseases at the University of Edinburgh, told The Mirror that scientists are most concerned about a measles-type virus.

‘A novel measles-like virus would pose a threat far worse than Covid,’ he said. 

‘Such a virus would have a much higher R number than the original variants of Covid – making it impossible to control by even the strictest lockdown.’

An R number describes the number of people that one infected person will pass on a virus to, on average.

‘This is the kind of pandemic that public health agencies around the world are most concerned about,’ he added.

Measles cases have been shown to wipe the memory of our immune systems, meaning a large outbreak could see a national rise in other infections. 

A 2019 Harvard Medical School study showed measles wiped out up to 75 per cent of antibodies protecting against the viruses or bacteria that a child was previously immune to.

In late January, a patient in the Midlands was diagnosed with H5N1 after ‘close and prolonged contact with a large number of infected birds’

Professor Isabel Oliver, Chief Scientific Officer for UKHSA, said the virus list is a tool to highlight how research can be targeted to increase UK preparedness against health threats.

‘We are using the tool as part of our conversations with the scientific community, to help ensure that investment is focused to where it can have the biggest impact.

‘We hope this will help to speed up vaccine and diagnostics development where it is most needed, to ensure we are fully prepared in our fight against potentially deadly pathogens.’

In September 2019, the now-defunct Public Health England also reported that increasing antibiotic resistance of bacteria could also turn into a potential Disease X.