Dozens of uncommon animals together with tigers, lions and cheetahs are dying as chook flu infiltrates zoos, with doubtlessly “grave implications” for endangered species, researchers have warned.
As a rising variety of zoos report animal deaths, scientists are involved that contaminated wild birds touchdown in enclosures could possibly be spreading it amongst captive animals. In the US, a cheetah, mountain lion, Indian goose and kookaburra have been among the many animals that died in Wildlife World Zoo close to Phoenix, in accordance with local media reports final week. San Francisco Zoo briefly closed its aviaries after a wild red-shouldered hawk was discovered lifeless on its grounds, and later examined optimistic for extremely pathogenic avian influenza (HPAIV). A uncommon red-breasted goose died at Woodland Park Zoo in Seattle, inflicting aviaries to shut and penguin feeding for guests to be suspended in November. These circumstances follow the deaths of 47 tigers, three lions, and a panther in zoos throughout south Vietnam over the summer season.
“Given the possibly deadly penalties of an HPAIV an infection in birds and in some mammals, equivalent to large cats, these infections might have grave implications for endangered animal species refuged in zoos,” stated Dr Connor Bamford, a virologist from Queen’s University Belfast.
Researchers say circumstances have in all probability emerged in zoos due to contaminated wild birds flying out and in of enclosures, and this tends to occur extra in the course of the migration season. Various US states, together with Louisiana, Missouri and Kansas, have reported a rise in chook flu circumstances, particularly in geese and waterfowl. There has been a “sharp bounce” of circumstances in Iowa, in accordance with state authorities, after “almost a yr” with no detections of the virus.
“We want to think about the best way to handle this case, both by way of enhancing zoo biosecurity or by vaccinating zoo animals. This occasion provides us one other wake-up name to the significance of HPAIV and its impacts on animals, and folks,” stated Bamford.
Researchers have warned for decades that this variant of chook flu might kill primates, rodents, pigs and rabbits, with studies of Bengal tigers and clouded leopards additionally being killed.
Infections in zoos weren’t sudden, stated virologist Dr Ed Hutchinson from Glasgow University. Visitors to zoos within the UK in recent times might have observed chook enclosures being briefly closed off or netted when the dangers of an infection by the H5N1 chook flu variant from wild birds have been identified to be excessive, he stated. “When zoos take care of animals from endangered species, taking measures to cut back the danger these animals face from H5N1, equivalent to limiting entry of untamed birds to enclosures, is especially vital.”
Zoos are normally residence to excessive densities of animals, and have various approaches to biosecurity, well being and welfare, and alternatives to be visited by wildlife. These components have an effect on their vulnerability, in accordance with Prof Rowland Kao, an epidemiologist on the University of Edinburgh. “There isn’t essentially one factor and one can not level to a selected zoo and say ‘they did this flawed’ – however these variable components, the numerous pathways this virus appears to be taking and the low viruses doses that may doubtlessly begin outbreaks, means that it’ll pop up in all types of locations,” he stated.
Bird flu viruses could be handed amongst all kinds of animals. In 2020, a variant unfold internationally, lastly reaching the Antarctic in late 2023, inflicting tens of millions of untamed animals to die throughout Eurasia, Africa, North America and South America on its route. In the US, it absolutely adapted to cattle, growing the danger of human infections.
The unfold continues in dairy farms, particularly in California – the US’s top-producing dairy state – the place nearly half of the state’s 1,300 farms have now been affected, and two farm workers examined optimistic this month. Two indoor cats are suspected to have died in Los Angeles after ingesting contaminated uncooked milk.
Prof Ian Brown, a virologist from the Pirbright Institute in Surrey, stated: “There is at all times a threat however zoos ought to take further hygiene precautions for such species – I do know some zoos have confined flamingos to their home throughout threat durations for unfold of virus.”
In some areas, such because the UK and the EU, licensed chook flu vaccines can be utilized on captive zoo animals. In the US this isn’t allowed.
