Bird flu cases have spread to almost every region of the world (Picture: Getty)
Disease X has been hitting the headlines in recent weeks as scientists, governments – and conspiracy theorists – prepare for the next pandemic.
However, one scientist warns that another pandemic is already here.
The disease, known as H5N1, emerged in domestic geese in China in 1997. In the following years it was largely confined to southeast Asia, but quickly spread from birds to humans in the region, killing between 40 and 50% of those infected.
Since 2020 however, the disease has spread like wildfire, not just geographically, reaching from the Arctic to the Antarctic and every continent except Oceania, but affecting dozens of non-avian species.
‘When people ask me what I think the next pandemic will be, I often say that we are in the midst of one – it’s just afflicting a great many species more than ours,’ said Dr Diana Bell, professor of conservation biology at the University of East Anglia.
Bird flu is affecting both wild and domestic birds (Picture: Getty)
‘I am referring to the highly pathogenic strain of avian influenza H5N1, otherwise known as bird flu, which has killed millions of birds and unknown numbers of mammals, particularly during the past three years.’
Referencing a study published this month, Dr Bell noted that, since 2020, 26 countries have reported at least 48 mammal species that have died from the virus.
In January, a polar bear in Alaska became the first of its species known to have died as a result of the disease.
Bird flu: Key numbers
882 Cases of bird flu in humans between January 1 and December 21, 2023 across 23 countries
461 Fatalities during the same time
48 The number of different mammal species from which individuals have died from the virus since 2020, including polar bears, dolphins and seals
500,000,000 The number of domestic bird that have died or been killed as a result of the recent outbreak
75% The percentage of UK great skuas killed after becoming infected
Other animals to have caught the virus include brown bears, black bears, lynx and mountain lions.
‘Not even the ocean is safe,’ said Dr Bell, writing for The Conversation. ‘Since 2020, 13 species of aquatic mammal have succumbed, including American sea lions, porpoises and dolphins, often dying in their thousands in South America.’
In March 2023, the first two dolphins to die of bird flu in UK waters were discovered at separate locations in Devon and Pembrokshire. They have not been the last.
Dolphins and other marine mammals have been infected (Picture: Getty/Image Source)
Other UK mammals struck down by the disease include seals, otters and foxes.
But the disease hasn’t just spread to wild animals. Another mammal, humans, have also caught the virus.
Between January 1 and December 21 last year, there were 882 reported cases of bird flu in humans across 23 countries – of which 461, or 52%, were fatal.
‘Of these fatal cases, more than half were in Vietnam, China, Cambodia and Laos,’ said Dr Bell.
A gannet in County Louth, Ireland killed by bird flu (Picture: Getty)
‘Poultry-to-human infections were first recorded in Cambodia in December 2003. Intermittent cases were reported until 2014, followed by a gap until 2023, yielding 41 deaths from 64 cases. The subtype of H5N1 virus responsible has been detected in poultry in Cambodia since 2014.
‘In the early 2000s, the H5N1 virus circulating had a high human mortality rate, so it is worrying that we are now starting to see people dying after contact with poultry again.’
Although the origins of Covid-19 have not been confirmed, one leading theory is a ‘zoonotic spillover’ event, as has happened with bird flu – when a virus passes from an infected animal to a person. The virus has not yet been transmitted from person to person, keeping the spread relatively limited, but bird flu is still considered by the World Health Organisation to be a major pandemic threat.
Most cases in humans occur from close contact with domestic poultry (Picture: Getty)
‘Scientists haven’t managed to completely sequence the virus in all affected species,’ said Dr Bell.
‘Research and continuous surveillance could tell us how adaptable it ultimately becomes, and whether it can jump to even more species. We know it can already infect humans – one or more genetic mutations may make it more infectious.’
Right now though, the biggest threat is to the world’s bird populations.
Research into the virus is continuing (Picture: Getty/Science Photo Libra)
‘The UK alone has lost more than 75% of its great skuas and seen a 25% decline in northern gannets,’ said Dr Bell. ‘Recent declines in sandwich terns and common terns were also largely driven by the virus.’
More than half a billion domestic birds have died or been culled around the world as a result of the virus.
Millions more wild birds have been affected, including those already endangered, such as the African penguin and California condor. After 21 condors died, authorities began testing out a bird flu vaccine on the iconic birds.
But a global vaccination programme is not realistic to combat this contagious and deadly disease.
Dr Diana Bell argues the world must change how it farms birds to help combat the disease (Picture: Getty)
As it continues to spread, Dr Bell argued the best step we can take is to change our attitude to farming.
‘How can we stem this tsunami of H5N1 and other avian influenzas?’ she said. ‘Completely overhaul poultry production on a global scale. Make farms self-sufficient in rearing eggs and chicks instead of exporting them internationally. The trend towards megafarms containing over a million birds must be stopped in its tracks.
‘To prevent the worst outcomes for this virus, we must revisit its primary source – the incubator of intensive poultry farms.’