Researchers at The Pirbright Institute have discovered that current global strategies to control bird flu are failing, with evidence of sustained transmission between mammals raising concerns about potential spillovers to humans.
Research conducted by The Pirbright Institute on sustained mammal-to-mammal bird flu transmission in diverse species reveals that current global control strategies are failing.
Writing in the scientific journal Nature, researchers analyzed whether outbreaks in European fur farms, South American marine mammals, and United States dairy cattle raise questions about whether humans are next. Led by zoonotic influenza specialist Dr. Thomas Peacock, the scientists evaluated how recent changes in the ecology and molecular evolution of H5N1 in wild and domestic birds increase opportunities for spillover to mammals.
The New Evolutionary Threats
They also weighed various evolutionary pathways that could turn the global H5N1 influenza panzootic into a human pandemic virus.
“Influenza A viruses (IAV) have caused more documented global pandemics in human history than any other pathogen. Historically, swine are considered optimal intermediary hosts that help avian influenza viruses adapt to mammals before jumping to humans,” said Dr. Peacock, who investigates the drivers of the current H5N1 avian influenza panzootic. “However, the altered ecology of H5N1 has opened the door to new evolutionary pathways.”
Control Challenges and Surveillance Shortcomings
The review highlights potential gaps in control mechanisms, including a reluctance to engage with modern vaccine and surveillance technologies and a dearth of data collection around the transmission of H5N1 between cows and to humans on US dairy farms.
While previous generations of US cattle producers had eradicated foot-and-mouth disease by rapidly sharing epidemiological data, the authors say months of missing data is leaving researchers, veterinarians, and policymakers in the dark.
“H5N1 is a reportable disease in poultry, but not mammals, in the US. The US Department of Agriculture requires H5N1 testing only in lactating cattle prior to interstate movement,” said Dr. Peacock.
Current practices for H5N1 testing in wildlife focus on carcasses, not monitoring animals whilst alive, the paper notes, providing opportunities for variants of H5N1 to spread silently undetected.
Silent Spread and Evolutionary Mechanisms
“What keeps scientists up at night is the possibility of unseen chains of transmission silently spreading through farm worker barracks, swine barns, or developing countries, evolving under the radar because testing criteria are narrow, government authorities are feared, or resources are thin.”
An evolutionary process of “genomic reassortment” in viruses with segmented genomes is driving the global panzootic outbreak. When two or more viruses co-infect a single host, they can swap entire segments during genome replication to create novel hybrids.
The reassortment between H5N8 and low pathogenicity avian influenza (LPAI) viruses that generated the panzootic H5N1 virus in the Americas is believed to have occurred in Europe or central Asia around 2020, infecting South American marine mammals and US dairy cattle.
Turning Point for HPAI in the West
The researchers say the prospect of H5N1 becoming continually present in Europe and the Americas is a turning point for High Pathogenicity Avian Influenza (HPAI).
“New control strategies are needed, including vaccination. Influenza vaccines are licensed for poultry that reduce disease burden, but do not prevent infection and have varying degrees of success.”
Stocks of H5 vaccine that are antigenically related to circulating viruses are available and could be produced at scale using mRNA platforms if H5N1 begins spreading in humans, the authors note.
Assessing the Potential Impact of an H5N1 Pandemic
“The severity of a future H5N1 pandemic remains unclear. Recent human infections with H5N1 have a substantially lower case fatality rate compared to prior H5N1 outbreak in Asia, where half of people with reported infections died. The lack of severity in US cases may be due to infection through the eye, rather than through viral pneumonia in the lung.”
Older people appear to have partial immunity to H5N1 due to childhood exposure, whereas younger people born since the 1968 H3N2 pandemic may be more susceptible to severe disease in a H5N1 pandemic.
Reference: “The global H5N1 influenza panzootic in mammals” by Thomas Peacock, Louise Moncla, Gytis Dudas, David VanInsberghe, Ksenia Sukhova, James O. Lloyd-Smith, Michael Worobey, Anice C. Lowen and Martha I. Nelson, 24 September 2024, Nature.
DOI: 10.1038/s41586-024-08054-z
Dr. Peacock’s work is funded by UKRI Biotechnology and Biological Sciences Research Council (BBSRC) via the Pirbright Institute’s Strategic Programme Grants (ISPGs) and the UK Medical Research Council / Department for Environment, Food and Rural Affairs FluTrailMap One Health consortium, and the BBSRC/DEFRA ‘FluTrailMap’ consortium.
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5 Comments
Of course “current global strategies to control bird flu are failing”. They have always failed. I believe the idea of such global control started within my lifetime, and is literally optimistic science-fiction. Humanity having true control over pandemics would be a significant step in evolution, but it remains beyond our capability for now.
The alarmism is absurd and unwelcome. However, this article by the Pirbright Institute impressively cites “a reluctance to engage with modern vaccine and surveillance technologies…(and) government authorities are feared”. That’s a remarkable admission after the past four years, of modern vaccines, surveillance technologies, and government authorities, all dystopian strategies leaving a pandemic unabated amidst mass hysteria. So, stop raising this particular alarm.
Of course the global strategies will fail. The average western-nation oik is such a dumb bunny that she/he/it will believe any crapulous theory put about by the internet that the deep-state is coming to get them and will refuse to wear a surgical mask in public, will adamantly refuse the historical proof that vaccines confer any anti-viral benefits and will continue to cough and sneeze in public without protecting others from their sprays of virus-added snot.
The WHO did a great job of stamping smallpox world-wide and even when being bombed and shot at in Gaza by fanatics of the Jewish faith has manged to prevent a major polio epidemic in that most-bombed city.
All that will enhance spread of bird-flu is the average crass selfishness and stupidity of Homo sapiens, his mobile phone and the internet.
Surgical mask only stops bacteria and bigger microbes, not viruses. Viruses are too small for the surgical mask fabric to contain. That’s why they were ineffective in this viral pandemic. Maybe you were referring to those FFP masks, but they aren’t normally worn by surgeons. And they’re expensive, so don’t count on them too much for the next pandemic.
Success of “historical” vaccines says nothing about the effectiveness of the newly developed vaccines for new diseases, so your argument is invalid. Polio and COVID are two entirely different beasts. Polio is a bacterial infection and anti-bacterial vaccines are known to be effective. COVID is a viral infection and anti-viral vaccines are still to this day ineffective against viral infections.
They haven’t even developed a successful vaccine for the common flu, one of the best known viral diseases, and you think they will develop it for a completely new disease? And rush it to production before the long term side-effects are known and expect that nothing bad will come out of that?
I would have said you were thouroughly brainwashed by the media, but since you’re still able to correctly point out that the Israelis are the fanatics, there’s some hope for you yet.
Oh yawn. Viruses ride on particles of snot, sneezed or coughed. A properly fitted surgical mask or even an N95 mask will stop those particles of snot. As granny said,’ Coughs and sneezes spread diseases, catch them in you handkerchiefzes’. Got the idea? And of course if that N95 mask limits the range of outgoing virus-laden missiles of snot it could also limit the intake of someone else’s virus-laden missile of snot. Hence the reduce the spread of virus-laden missiles of snot and the rate of cross-infection diminishes. An interesting and most peculiar notion for the average human to consider.
Poliomyelitis. According to Dr Google, ‘Polio (poliomyelitis) is a disease caused by poliovirus. It causes mild or no symptoms in most people, but in some people it can cause paralysis or death. There are three variations of poliovirus, called wild poliovirus type 1, 2 and 3 (WPV1, WPV2 and WPV3).’
I have never heard of a virus being called a bacterium, but in these days of shape-changing across the internet, ‘most anythung’ is possible.
As for anti-viral vaccines, their efficacy is controlled by the rate of mutation of the virus in question. Flu virus do seem to work adequatey (nothing is perfect) as long as one gets one’s yearly vaccination .
A few tyopographic errors. You may work out which ones are correct.