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Almost 23 million dead chickens and turkeys: truck in front of an egg farm in the USA
Photo: Scott Olson/Getty Images
In the United States, visitors to zoos may not see birds right now -- though a few penguins waddle around behind glass in their enclosures.
The reason: Zoos across North America are keeping their birds safe from bird flu and trying to keep them indoors away from people and wildlife.
The highly contagious and potentially deadly bird flu is currently rampant in the United States.
No outbreaks in zoos have yet been reported, but wild birds have been found dead that have been found to have avian influenza.
A wild duck that died on the grounds of the Blank Park Zoo in Des Moines, Iowa last month has tested positive, the zoo spokesman said.
Almost 23 million chickens and turkeys have already been killed in the United States to stem the spread of the virus.
Recently, egg prices in the country have skyrocketed.
According to the Department of Agriculture, a range of $2.82 to $2.85 (around €2.60) was recently due for a dozen eggs on the reference market in the Midwest of the country.
The cost was 50 percent higher than in February and just below the record high of over $3 in 2015, when the worst bird flu in the country's history raged.
Back then, 50 million animals had to be killed.
It would be particularly dramatic for the zoos if valuable birds had to be culled.
"That would be extremely devastating," said Maria Franke, director of animal welfare at the Toronto Zoo.
She points out that many employees have developed a close relationship with the animals.
Covered outdoor enclosures are currently being checked in the zoo and nets intended to keep wild birds away.
Birds shed the virus, mostly the H5N1 strain, through their feces and nasal discharge.
According to experts, the virus can be spread through contaminated equipment, clothes, boots.
Research has shown that small birds that invade zoo exhibits or buildings can also spread the flu, and that mice can even carry the virus indoors.
So far no cases of bird flu in humans
In the United States, too, when cases of bird flu are found in poultry, all animals in a flock or farm must be killed.
However, the US Department of Agriculture has indicated that zoos may be able to avoid this by isolating infected birds.
As a result, one of the precautions zoos are taking is to keep birds in smaller groups so that if infected, only a few would be affected.
However, the final decision to kill animals is made by the authorities and state veterinarians.
The authorities stress that avian flu does not compromise the safety of meat or eggs, nor pose a significant risk to human health if the products are well cooked.
Infected birds must not be used for food production anyway.
According to the Centers for Disease Control and Prevention, no human cases of bird flu have been reported in the United States.
Bird flu is also rampant in German zoos.
The virus was detected in the Karlsruhe Zoo in early February.
Two Hawaiian geese and a pelican were the first victims.
The zoo had to close.
The virus was detected in around 90 animals in the following days.
The director spoke of an unprecedented extent in a German zoo.
According to the Friedrich Loeffler Institute (FLI), Europe experienced the worst wave of avian influenza to date from autumn 2020 to April 2021.
The bird flu subtype H5N1 dominates.
As with the corona virus, the spread usually decreases in summer due to high temperatures and then increases again in autumn.
Since mid-October 2021, hundreds of infected wild birds from at least twelve federal states and over 50 outbreaks in poultry and kept birds have been reported in Germany.
The bird flu, also known as avian influenza, is an influenza A infection, the virus is divided into different subtypes.
H5N8 occurs in wild birds and occasionally on poultry farms.
People were also infected for the first time last year.
Seven workers at a Russian poultry farm fell ill and suffered from mild symptoms.
However, transmission occurs only rarely and only with close contact.
In addition, no human-to-human transmission is known.
So far only infections with the bird flu virus H5N1 in humans were known.
The virus first emerged in major Southeast Asia and spread to many parts of the world in 2004.
Not only wild and farmed poultry were infected, time and again people too.
Most had previously had close contact with the animals.
According to the Robert Koch Institute, according to previous experience, the virus only seems to be transmitted from animals to humans in close contact with sick or dead birds and their products or excretions.
joe/AP/dpa