Since May, plenty of poultry farms around Australia have experienced outbreaks. Avian influenza, or bird flu. The outbreak has been devastating for affected poultry farms, requiring large-scale culls, and has had devastating effects on the country. Egg supply.
Poultry farm outbreaks have been linked to bird flu strains that originate from H7 (comparable to H7N3 and H7N8). But the strain of best concern straight away is a distinct strain – H5N1.
This strain is spreading rapidly throughout the world, and may cause More serious illness and death in poultry, birds and mammals.
Experts are warning H5N1 may reach Australia soon. And while bird flu shouldn’t be currently spreading between humans, that would change in the long run.
So where are we with the bird flu vaccine?
More about bird flu
H5N1 emerged first. South China in 1996.
Strains like H5N1 are further divided into differing types called clades. Since emerging in 2020, clade 2.3.4.4b has spread all over the world, causing experts to fret. Recently, it’s spreading not only in wild birds and chickens, but in addition in dairy cows, especially United States.
While H5N1 has not yet been detected in birds or other wildlife in Australia, because it is spreading in other regions, There are concerns We have the chance Check it out here soon. CSIRO experts warned this week that there’s a risk of H5N1 being imported. More this year in comparison with previous years.
Fortunately, cases in humans remain rare. Five human affairs H5N1 clade 2.3.4.4b has been reported within the US since 2022, all of which had close contact with dairy cows or chickens, and About ten others anywhere else on the earth.
There was a single imported human case of H5N1. In Australia In a baby who had returned from abroad earlier this 12 months, but of a distinct class.
The biggest challenge with influenza viruses is that they will change quite easily. It is probably going that a few of these changes may give the virus the flexibility to be transmitted from individual to individual more easily. This may lead to widespread transmission, or a pandemic, all over the world.
We have already got some vaccines.
Given that H5N1 viruses have been around for some time, we actually have already got some. Vaccines Designed to guard against this strain of bird flu within the event of continued transmission to humans. The US approved one from Sanofi Pasteur. Back in 2007the European Union approved one. GSK in 2008And Australia In the identical 12 months one was approved from CSL Limited.
Older H5N1 vaccines were traditional egg-based vaccines, which work by inactivating the virus by growing it in fertilized chicken eggs, then injecting it into the muscle to coach our immune system to reply.
more recently, CSL Securis Made a Cell-based H5N1 vaccine. The shot is predicated on technology already used to make their seasonal flu vaccine, where the virus is grown in cultured mammalian cells (as a substitute of eggs). Developing a vaccine that doesn’t require chicken eggs to provide is prudent within the context of bird flu, which can limit egg availability.
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While the danger in humans is less. World Health Organization advises that humans don’t have to be vaccinated against bird flu at this stage.
That said, Finland plans to roll out CSL Seqirus shots to those people immediately. Most at risk (People are routinely exposed to animals that could be infected), it became the primary country to vaccinate against H5N1.
While research has suggested. Current vaccines Induces an immune response that may provide sufficient protection against currently circulating strains, vaccines based on older versions of H5N1, or vaccines developed more recently, is probably not a great match for future bird flu strains. .
What about mRNA vaccines?
mRNA vaccine technology is now well established for COVID, while an mRNA vaccine Against the RSV (respiratory syncytial virus) was recently approved within the United States.
mRNA (messenger RNA) vaccines work primarily by instructing our immune system to make proteins, often bits found on the surface of viruses. Our immune system then recognizes and responds to those proteins to guard us once we encounter the virus.
The technology also offers promise for bird flu vaccines. Moderna began clinical trials in 2023 and recently for mRNA vaccines against each H5 and H7 strains. Secure funding to proceed late-stage development. Other corporations including GSK And Pfizer Also working on an mRNA vaccine against H5N1.
![A man is vaccinated.](https://images.theconversation.com/files/607181/original/file-20240716-17-4gihqz.jpg?ixlib=rb-4.1.0&q=45&auto=format&w=754&fit=clip)
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An advantage of this technology is that if the virus is significantly altered from the circulating version at a given time, the mRNA vaccine Can be adapted These changes Quite quickly.
Other methods are also being investigated, including a “universal” flu vaccine that may protect against every kind of flu. But it’s unlikely to be available soon.
Being primarily an avian virus, one other strategy is to vaccinate the birds themselves. In some countries where bird flu is persistently present in birds, comparable to Egypt and China, vaccinate especially poultry It has become normal for a while.
What next?
With the increasing global spread of H5N1 and the increasing variety of infected species, there are concerns in regards to the potential of this strain to cause a pandemic.
If we do see an outbreak of bird flu, fortunately we’re probably in a greater position than before Answer. Not only have we learned quite a bit lately from the response to other infectious diseases, particularly COVID, but technology and the flexibility to Make a vaccine fast It has come a good distance.
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