HEALTH officials have raised the pandemic risk of bird flu from three to four on a six-tier scale after the virus jumped from cows to humans.
The UK Health Security Agency (UKHSA) says “there is high uncertainty regarding the trajectory of the outbreak and there is no apparent reduction in transmission in response to the biosecurity measures that have been introduced to date.”
To make sure the country is prepared for a possible outbreak of the highly pathogenic H5N1 in humans, officials monitor its spread and assess its risk.
This move comes after four dairy workers in the US tested positive for the bug in a scary advancement that saw the virus jump from birds to cows, spread between them and end up in humans.
To become pandemic, a virus needs to be able to infect humans easily and spread among them.
So far, there is no evidence that bird flu can be transmitted between people.
However, experts fear the sheer scale of the spread could give the virus more opportunities to mutate, which could accidentally enable H5N1 to better spread between mammals – and potentially humans.
“The recent outbreak in US dairy cattle demonstrates that influenza A(H5N1),” Dr Susan Hopkins, the UKHSA chief medical advisor, said.
“While the current risk to the UK population from influenza A(H5N1) virus remains very low, an outbreak of this kind can increase the opportunities the virus has to evolve to spread between people at some point in the future.
“This is because the virus may adapt directly during transmission between mammals or may reassort with other flu viruses in humans or other mammals.”
Bird flu’s new level four risk means the disease has experienced ‘sustained multiple multispecies outbreaks’ and ‘increasing human zoonotic cases or limited person to person exposure’, according to the report published earlier this month.
To reach level five, the virus would have to cause ‘human outbreaks (larger or without identified zoonotic links)’ meaning it spreads between humans.
For level six. the UK would have to see ‘sustained’ transmission between humans.
Dr Susan said the UKHSA would “continue to monitor the situation closely.
“UKHSA has established preparations in place for detections of human cases of avian flu and stands ready to initiate an appropriate public health response should it be needed.”
In government guidance issued in May, Brits were advised to stay at least two meters away from wild birds because of bird flu fears.
People should avoid all contact with wild birds, which includes pigeons, swans, and seagulls, UKHSA said.
Some countries are discussing deploying vaccines or are working to secure supplies.
In November, health officials told the Sun the UK was drawing up plans to stockpile vaccines in case of a bird flu pandemic in humans.
In May, the World Health Organisation (WHO) initiated a review of available influenza vaccines and confirmed that they would work against the H5N1 virus circulating in cattle.
“Although the current public health risk is low, WHO is operating in a constant state of readiness for a potential influenza pandemic,” said Maria Van Kerkhove, who heads epidemic and pandemic preparedness and prevention at the WHO.
By health reporter, Isabel Shaw
BIRD flu is running rampant in wildlife around the world and is now spreading in cows.
This increase in transmission has given the virus lots of opportunities to mutate – a process where a pathogen changes and can become more dangerous.
Scientists fear it’s only a matter of time before one of these mutations makes it better at spreading among mammals – and potentially humans.
Some experts believe the virus could already be spreading among some animal species.
So far, there is no evidence that H5N1 can spread between humans.
But in the hundreds of cases where humans have been infected through contact with animals over the past 20 years, the mortality rate is high.
From 2003 to July 2024, 904 cases and 463 deaths caused by H5N1 have been reported worldwide from 23 countries, according to the World Health Organisation.
This puts the case fatality rate at 51 per cent.
Leading scientists have already warned an influenza is the pathogen most likely to trigger a new pandemic in the near future.
The prospect of a flu pandemic is alarming.
Although scientists have pointed out that vaccines against many strains, including H5N1, have already been developed, others are still in the pipeline
This month, US scientists announced a universal jab that protects against every form of flu – including bird flu- could be available within five years,
In June, the European Commission bought around 700,000 doses of a flu vaccine manufactured by CSL Seqirus, in the UK, with the option to buy another 40million.
The vaccine protects against H5 strains of influenza A.
Meanwhile, Finland has already begun vaccinating people against avian influenza, focusing on high-risk workers at fur and poultry farms.
In the US, scientists at pharmaceutical giant Moderna are developing an mRNA vaccine against bird flu.
