Architects of Britain’s Covid lockdowns are modelling how many Brits could die in a bird flu outbreak amid growing fears that the virus may soon jump to humans.
UK Health Security Agency (UKHSA) officials are now developing ‘scenarios of early human transmission’ to ‘facilitate preparedness’.
Only one Brit has caught the killer illness since the unprecedented bird flu outbreak began sweeping the world in October 2021.
Yet fears of another pandemic are quickly notching up.
Cases of the H5N1 strain have already jumped from birds to mammals.
It has sparked huge concern among top virologists that the deadly pathogen is now one step closer to spreading in humans — a hurdle which has so far stopped it from triggering a pandemic.
Among those working on the models is Professor Neil Ferguson, an epidemiologist whose chilling projections of the Covid outbreak led the UK Government to impose the first lockdown.
It comes as a dozen people in Cambodia are suspected of being infected with H5N1 in the same province where an 11-year-old girl died on Wednesday — raising fears the virus may even be spreading from human to human.
This picture released by Cambodia’s Communicable Disease Control Department (CDCD) on February 23, 2023, shows villagers posing with posters about H5N1 virus threats, in Prey Veng province – where a girl died from the virus this week and 12 more are suspected to have been infected
Among those working on the models is Professor Neil Ferguson (pictured), an epidemiologist whose modelling of the Covid outbreak led the UK Government to impose the first lockdown
The Khmer Times – a local newspaper – reported that the suspected patients have all been tested for the virus and are waiting on lab confirmation, four of whom are symptomatic.
Dr Arturo Casadevall, an immunologist at Johns Hopkins, reacted to the suspected outbreak in Cambodia. He wrote on Twitter: ‘Key information is whether the 12 infected people obtained it from a bird source or from human-to-human transmission, which would be very worrisome.’
Dr Eric Feigl-Ding, an epidemiologist and Chief of COVID Task Force at the New England Complex Systems Institute, tweeted: ‘Hope this wasn’t human to human, but I’m now getting to be worried,’
H5N1 was first detected in chickens in Scotland in 1959, and again in China and Hong Kong in 1996. It first was detected in humans in 1997.
Human-to-human transmission of H5N1 is incredibly rare, but not impossible. In 1997, officials confirmed 18 H5N1 cases in Hong Kong, some of which were acquired through human-to-human transmission. The outbreak stayed relatively small, though. And did not spiral into a massive issue at either the local or global level.
This recent outbreak has caused particular concern. More than 15million domesticated birds, and countless wild animals, have been struck down by the virus.
There is nothing to be done that can prevent the spread among wild birds, but officials are working to keep domesticated populations away from them. In the UK, all farmed chickens are now required to stay indoors.
Among those working on the models is Professor Neil Ferguson, an epidemiologist whose modelling of the Covid outbreak led the UK Government to impose the first lockdown.
The above map shows locations where there is a growing risk of a zoonotic virus outbreak. Dr Jennifer Nuzzo, a public health expert at Brown University in Rhode Island, warned that Texas was also a potential epicenter
Pictured: A National Trust ranger clears deceased birds from Staple Island in July 2022
The UKHSA graph shows the number of bird flu cases, by region in England, confirmed among kept and wild birds between October 2022 and February 2023
A young girl in Cambodia has died from the H5N1 bird flu. She was infected with the virus last week. She is the nation’s first case since 2014 (file photo)
The above map shows bird flu cases detected in poultry facilities (left) and in wild birds (right) in 2022 and 2023. The WHO has warned the world to prepare for a potential bird flu pandemic saying the virus could jump to humans
Before the cases in Cambodia, only one case of H5N1 in humans had been detected this year. Cases in humans have been rare in recent years
In an update today, the UKHSA confirmed that its Avian Influenza Technical Group – which includes Professor Ferguson and around two dozen other experts – calculated how an outbreak could sweep the UK.
Under a ‘mild scenario’, the scientists estimated that one in 400 people who caught bird flu would die due to the virus.
This infection fatality rate (IFR) of 0.25 per cent is similar to Covid’s in mid-2021 and the 2009 bird flu outbreak.
But under a ‘more severe scenario’, the virus would be fatal among one in 40 people who became infected (an IFR of 2.5 per cent).
However, the World Health Organization warns that of the 868 human H5N1 cases reported to it over the last two decades, 456 – just over half – have been fatal.
Bird flu outbreak: Everything you need to know
What is it?
Avian flu is an infectious type of influenza that spreads among birds.
In rare cases, it can be transmitted to humans through close contact with a dead or alive infected bird.
This includes touching infected birds, their droppings or bedding. People can also catch bird flu if they kill or prepare infected poultry for eating.
Wild birds are carriers, especially through migration.
As they cluster together to breed, the virus spreads rapidly and is then carried to other parts of the globe.
New strains tend to appear first in Asia, from where more than 60 species of shore birds, waders and waterfowl head off to Alaska to breed and mix with migratory birds from the US. Others go west and infect European species.
What strain is currently spreading?
So far the new virus has been detected in some 80million birds and poultry globally since September 2021 — double the previous record the year before.
Not only is the virus spreading at speed, it is also killing at an unprecedented level, leading some experts to say this is the deadliest variant so far.
Millions of chickens and turkeys in the UK have been culled or put into lockdown, affecting the availability of Christmas turkey and free-range eggs.
Can it infect people?
Yes, but only 860 human cases have been reported to the World Health Organization since 2003.
The risk to people has been deemed ‘low’.
But people are strongly urged not to touch sick or dead birds because the virus is lethal, killing 56 per cent of people it does manage to infect.
The Avian Influenza Technical Group noted that while other H5N1 outbreaks have had ‘much higher fatality estimates’, these did not involve sustained human-to-human transmission, so are not ‘directly comparable’.
Unlike the Covid pandemic, the scientists said that a bird flu outbreak could be more deadly among the young, rather than the elderly – as was seen in the 1918 flu pandemic.
Professor Ferguson has admitted he became ‘something of a marmite figure’ and that he ‘made mistakes’ and ‘oversimplified things’ during the pandemic.
Modelling from the epidemiologist and his colleagues at Imperial College London in March 2020 predicted the NHS would be overwhelmed within weeks and a terrible death toll would arise if nothing was done to stop the spread of the disease.
Professor Ferguson has said while it had been challenging for most Western governments to act in a timely manner, the science throughout the crisis ‘had basically been right’.
In light of the modelling, the UKHSA said it would continue to investigate how it could detect cases if there was an outbreak among people.
This could see Covid-style lateral flow tests rolled out to test Brits for bird flu, it said.
The UKHSA said it is investigating whether the swabs, which provided results in as little as 15 minutes during the Covid pandemic, would detect the circulating deadly H5N1 strain.
It is also probing whether a blood test could be developed that detects antibodies against the virus.
Genetic mutations in positive samples are also being monitored for any signal that the virus is mutating to become a bigger risk to people.
It will ‘remain vigilant’ over whether the ‘constantly’ evolving virus, which kills over half of those it infects, has gained mutations that may better allow it spread among people.
The UKHSA also noted that the ‘very high levels’ of transmission in wild birds presents a ‘constant risk’.
The agency noted that there is ‘no evidence so far that the virus is getting better at infecting humans or other mammals’ and data suggests H5N1 ‘does not pass easily to people’.
But it warned there is an ‘increased chance’ of people coming into contact with the virus due to the sky-high rates among birds.
It urged Brits to avoid contact with sick or dead wild birds in parks and waterways and wash their hands after feeding wild birds, to reduce the risk of exposure to bird flu.
Dr Meera Chand, incident director for avian influenza at the UKHSA, said: ‘The latest evidence suggests that the avian influenza viruses we’re seeing circulating in birds do not currently spread easily to people.
‘However, viruses constantly evolve, and we remain vigilant for any evidence of changing risk to the population, as well as working with partners to address gaps in the scientific evidence.’
The weekly update also revealed that 2,310 Brits have been monitored by UKHSA officials between October 1 2022 and February 14 after being exposed to bird flu.
Imperial College London published a paper in March 2020 on the potential impact of coronavirus. It weighed up options on how a lockdown could reduce demand on hospitals
The UKHSA graph shows the number of cases of the H5N1 bird flu strain detected among mammals, such as foxes and otters, between October 2021 and January 2023 in England (light blue), Scotland (dark blue) and Wales (green)
The graph, from the UKHSA, displays cases of H5N1 among mammals worldwide between January 2020 and February 2023
The UKHSA graphic shows the number of people exposed to bird flu between October 2022 and February 2023, by region in England
But samples taken from those who developed any cold or flu-like symptoms in the three weeks after coming into contact with the virus revealed none had become infected.
The UK’s avian flu outbreak began in October 2021, after health chiefs spotted the virus was still spreading among birds after the spring and summer months – when they usually decline.
Health chiefs have warned that the winter migration of wild birds is likely to further hike avian flu transmission in the coming months. This is because migrating birds can infect local kept and wild birds, driving up cases.
As well as record cases in birds, the virus has also been spotted in other animals, such as foxes, otters and seals in the UK, mink in Spain and sea lions in Peru.
This sparked concern that the virus may be spreading between the mammals, which would indicate it had picked up a troublesome mutation that could, in theory, make it easier for humans to become infected.
Nearly 300 confirmed cases of H5N1 have been detected among birds in England since the current outbreak began in October 2021. However, the true toll is thought to be much higher. The map shows the areas where cases have been detected and where 3km (blue dots) and 10km (yellow dots) protection zones have been imposed — meaning enhanced infection control measures are in place among those who have birds
Pictured: A dead bird in Queens Park in Heywood, Rochdale, amid the bird flu outbreak
Alan Gosling (pictured), a retired engineer in Devon, caught the virus after his ducks, some of which lived inside his home, became infected. No one else caught the virus
Further testing is still required to determine if mammals are transmitting the virus, however.
But there has only been one case of a British person becoming infected since the current outbreak began.
Alan Gosling, a retired engineer in Devon, caught the virus in early 2022 after his ducks, some of which lived inside his home, became infected.
Cambodian Health Minister Mam Bunheng warned that bird flu poses an exceptionally high risk to children who may be feeding or collecting eggs from domesticated poultry, playing with the birds or cleaning their cages.
The virus can spread to humans when a person has an open wound exposed to an infected bird. Usually, infections occur when a person is pecked or clawed by a bird. Transmission can also occur from a dead bird to a human.
World Health Organization (WHO) Director-General Tedros Adhanom Ghebreyesus said the agency still deems the risk of bird flu to humans as low. ‘But we cannot assume that will remain the case, and we must prepare for any change in the status quo,’ he said earlier this month.
He advised people not to touch dead or sick wild animals and for countries to strengthen their surveillance of settings where people and animals interact.
Cambodia had 56 human cases of H5N1 from 2003 through 2014, and 37 of them were fatal, according to the World Health Organization.
Each person had samples were taken for analysis for a lab in Phnom Penh, the nation’s capital, around 40 miles west of the rural province of Prey Veng, where the suspected cases were detected.
It is unclear whether this group of people had any interaction with the 11-year-old girl, or if they come from the same part of the province. It is also unclear whether they had interactions with any birds that could be carrying the virus.
More than 1.1million people live in Prey Veng, it is the third most populous province in the country, and known to be densely populated.
Prey Veng is also were the girl who eventually died lived. She became ill on February 16 and was sent to be treated at a hospital in the capital
She was diagnosed last Wednesday after suffering a fever up to 39C (102F) with coughing and throat pain. She died shortly after her diagnosis, the Health Ministry said in a statement Wednesday night.
There are no treatments designed specifically for humans infected with bird flu, let alone H5N1. Those who fall ill are treated with regular antiviral drugs such as Zanamivir and Peramivir.
In case of an outbreak, the US does have a stockpile of vaccines designed to prevent infection from H5N1.
It is sold under the name Audenz and was approved in 2021 by the Food and Drug Administration for people six months and older. It is a two-dose vaccine.
Health officials have taken samples from a dead wild bird at a conservation area near the Prey Veng girl’s home, the ministry said in another statement Thursday. It said teams in the area would also warn residents about touching dead and sick birds.
Experts warn that the virus is adapting in ways that allow it to cause outbreaks in other mammals – increasing the risk it could spread among people.
In October, an outbreak of the bird flu ravaged a population of 52,000 mink at a farm in Spain.
Some of the critters were initially infected by eating meat from birds that died while infected.
There were also signs of mink-to-mink spread of the flu, which is unusual for a mammal population and signals a change to the virus.
In Peru, 716 sea lions were found to have died from the bird flu in recent weeks. Local officials worry that the virus has also spread between the animals – which are also mammals.
The world is suffering what has been described as the worst bird flu outbreak ever recorded, with over 58million birds in the US alone having been culled or killed by the virus over the past year.
Unlike usual spikes in bird flu that last months, this outbreak sustained itself through the summer of 2022 and is spread almost entirely by wild birds
For the US poultry industry the battle has been deadliest in history. The outbreak has ramped up pressure on the industry to protect its flocks and forced them to kill millions of birds to avoid the deadly spread.
To protect their domesticated birds, farmers around the country have installed extra protections from wild flocks, including installing vibrating mechanisms in containers holding chicken feed to avoid worker contamination.
The disease is so contagious that wind can carry bird droppings to a barn vent causing the virus to circulate inside.
It can also be spread to commercial flocks by workers stepping on wild-bird feces outside of a barn and spreading it inside with each step.
Some farms have installed motion-detecting alarms, known as ‘sound cannons’, as well as bright laser systems to shoo away wild birds without harming them.
The recent spread of the virus has lead to rampant inflation of both chicken and egg prices in the US and across the world.
Federal officials also fear that the spring migration of birds could also reignite spread of the deadly virus.
A Cambodian man carries dead chickens at a market in Phnom Penh – the capital and most populous city of Cambodia
It comes as experts express greater fears of the threat of zoonotic diseases spreading in America. Last week, experts at Harvard University, in Cambridge, Massachusetts, and New York University, warned about the risks of zoonotic transmission.
In an editorial, they accuse the US of being too obsessed with external threats such as bioterrorism and lab leaks while failing to keep a close eye on the risks in its own backyard.
They called for an overhaul of regulatory agencies, including the US Department of Agriculture.
Experts have already warned that the next zoonotic outbreak could occur in China — because of its wet food markets — and Rwanda and Brazil — where urbanization and expanding agriculture are bringing people into contact with wild animals they would previously have been separated from.
But they also warn that Texas — one of the world’s leading producers of meat — could also be a hotbed for new dangerous viruses.
In the piece, they urged: ‘What is needed is not simply for agencies to do their jobs better or to paper over the gaps, but a fundamental restructuring of the way that human-animal interfaces are governed.
‘A One Health approach, which NBS-22 claims as its guiding principle, would take the health of other living things not merely as the occasional means or obstacles to human health, but as continuous with it.
‘The first step in implementing such an approach would be to create a high-level process for integrating the broken mosaic of multiple agencies, with their unclear and sometimes competing mandates, into an effective, comprehensive regime.’
Figures show 10billion animals were killed for meat in the US in 2022, the highest number on record and up 204million in 2021.
The country is also a leading importer of live animals — which could harbor diseases — bringing in about 200million annually according to estimates.
There is also a large wild game market which raises about 40million animals annually.
Scientists warned that infections could jump from animals to humans at any stage in the meat supply chain — from the rearing facility right through to slaughter and where it is consumed.
They warn there is a higher risk with live imported animals because these come into the US with no health and safety checks on arrival, meaning they could bring new diseases into the country.
There is also a higher risk with game animals, because these are not sanitized or regulated before being eaten.
Evidence is mounting that the US is already facing a growing number of animal-to-human infections.
The country recorded more animal-to-human infections in the second half of the 20th century than any other country globally, the scientists said.