First outbreak of highly pathogenic H5N9 that were reported in US ducks

In the United States, bird flu has never been found in the United States in poultry on a California farm.

The virus, known as highly pathogenic H5N9, is a kind of influenza that is also referred to as “bird flu”. This is not the same type of bird flu that has already spread to dairy cow and poultry farms in the USA, which leads to at least several dozen infections in humans. This virus is called H5N1.

What is H5N9? How does it differ from H5N1 and should we also make ourselves concerned about it?

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What is H5N9?

H5N9 is a highly pathogenic virus of bird flu (or bird flu) that bears some structural similarities to H5N1.

“Low pathogenic” H5N9 viruses were previously detected in birds in the United States and elsewhere in the world, which dates back to the 1960s. However, these infections are usually associated with less severe symptoms than “high -distance” tribes. This is the first time that high -distance H5N9 has been observed in the USA, and these fatal tribes are also quite unusual worldwide.

How did H5N9 be created?

New subtypes and influenza tribes can appear if viruses absorb random genetic mutations when they multiply, and when several viruses exchange genetic information with each other. This latter process is known as genetic reforms and usually occurs when an organism is infected with at least two different viruses.

Some experts suspect that H5N9 among the ducks in California due to the genetic reforms between circulating H5N1 viruses and other flu viruses that contain the N9 protein may have occurred. (“H5” and “N9” are two proteins that can be found on the surface of the virus and the bird flu give their names.)

H5N1 was also found in the birds on the farm, so that, according to a report by the World Organization for Animal Health (WOAH), this could be plausible, which monitors the outbreaks of animals in animals worldwide.

Such a redesign can lead to “unpredictable new viruses”, Angela Rasmussen, a virologist at the University of Saskatchewan in Canada, wrote about X.

She added that ducks could be great taverns so that genetic reforms can take place because, unlike chickens, they do not become very sick from many bird flu viruses. While an infected chicken would die quickly, ducks can survive and the disease can continue to spread to new hosts.

What happens on the farm on which H5N9 was discovered?

In the report of January 24, the Woah announced that H5N9 had been identified on a duck farm in Merced County, California. The current outbreak, which was confirmed according to the report on January 13, is closely monitored by civil servants.

“The USDA Animal and Plant Health Inspection Service (Aphis), in connection with the officials of animal health and the wild animal of animal administrations, conducts epidemiological studies comprehensive and improved the surveillance to the events HPAI (highly pathogenic bird influenza)” “The report.

In order to prevent further spread of the infection, all almost 119,000 birds have now been selected on the farm. These bird flu viruses are referred to as “highly pathogen”, since they are extremely fatal for certain poultry – like chickens, and the equipment of a exposed herd is usually considered the best way in which additional herds can get sick.

Why is bird flu affected?

Scientists have recently increasingly expressed that bird flu could mutate into a form that spreads easily in humans and triggers a pandemic. This happened in historical pandemics such as the “Spanish flu” in 1918 and the “Asian flu” in 1957.

People can infect bird fluenza when the virus gets into the eyes, nose or mouth or if it is inhaled in the air in the form of droplets. However, not all bird flu viruses are equipped to infect people efficiently and then spread between them. If the viruses have more chances to spread to new animals, they have a higher probability of recovering this ability and harm.

H5N1 has expanded to new countries in recent years, including the USA, it has infected wild wild birds and poultry and has also jumped into different mammals, including cattle and domestic cats. H5N1 has infected more than 900 people worldwide since its discovery, and at least 67 people were infected in the United States in the United States. In December 2024, a woman in Louisiana was the first person in the United States who died as a result of an H5N1 infection.

How does H5N9 differ from H5N1?

Vogel -Influenzaviren occur in various subtypes, which are designated according to subtle variations in the structure of two key proteins on the surface of the virus: hemagglutinin (h) and neuraminidase (n). H5N9 and H5N1 have the same hemagglutinin protein, but another neuraminidase protein.

The specific combination of H and N protein of a virus determines a number of important features, e.g.

In addition to the difference in their neuraminidase proteins, H5N9 differs in different ways from H5N1.

For example, H5N1 infections are more common in humans and are considered the deadliest of all highly pathogenic bird fluenza tribes in humans and chickens.

Is H5N9 a risk for humans?

So far, little is known about whether H5N9 could spread to humans and possibly cause a pandemic.

On its website, the Centers for Disease Control and Prevention (CDC) currently says that the risk of public health of the H5 bird flu is “low”, but the agency “carefully observes the situation and works with states to use people with animal exposure monitor.

From January 18, there was no evidence that the H5 bird flu spread from one person to another in the United States

“The combination H5N9 is not new and other versions, as well as H5N5,” Florian Krammer, professor of Vaccinology at the Icahn School of Medicine on Mount Sinai in New York, told CBS News. “Just because this has now been determined does not necessarily mean trouble,” he emphasized.

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