Workers near a dead seal lying on the shore of the Caspian sea in the Russian republic of Dagestan on May 5, 2021. It is also why there had never been any large-scale cases of mammal-to-mammal transmission. This forced adaptation to replicating in the lungs is why only poultry workers, who breathe in contaminated faecal dust, are typically infected. In order to infect humans, said William Schaffner, a professor of medicine at Vanderbilt University’s Division of Infectious Diseases, the virus has to attach to receptors in the lungs - receptors it lacks the ability to readily bond with. In birds, said Sawatzki, H5N1 is primarily a gastrointestinal infection that spreads through faeces. With the rise in outbreaks among poultry and wild birds, the increase in mammalian infections is not surprising, Kaitlin Sawatzki, a molecular virologist and animal surveillance coordinator with Tufts University, told Al Jazeera, describing the cases of spillover to mammals as individual incidents. In 2022, the clan made its move to Central and South America, as well. By the end of 2021, the 2.3.4.4b clade was not only behind the vast majority of new cases in Europe, Asia, and the Middle East - but had also jumped to Canada and the US. Then, in 2021, a front-running clade, or family, of H5N1 variants executed a mafia-esque takeover. In all, the virus has killed 457 people in the last 20 years. All the way through 2020, the number of host species and populations expanded exponentially. Between 20, 468 human cases, primarily among poultry workers, resulted in 282 deaths. This enabled the virus to spread further around Asia, Europe and the Middle East. The dense quarters and high populations favoured the emergence of more virulent strains, which jumped to wild bird populations in 2005. Speaking to Al Jazeera, Isabella Monne, a researcher with Italy’s Istituto Zooprofilattico Sperimentale delle Venezie who recently studied the mink outbreak in Galicia, noted that in 1996, H5N1 emerged in Chinese poultry production. But to truly understand H5N1 and contextualise its recent proliferation, one has to rewind to the late 1990s in China. The strain typically of concern is H5N1, each letter-number pair classifying the types of bonding proteins the virus has on the surface. A woman steps on lime, set up by health workers who created a sanitation perimeter near chicken farms, as she walks home amid a health alert due to a bird flu outbreak in Sacaba, Bolivia, Tuesday, Janu The mafia takes overĪvian influenza is actually a catch-all term for several strains of flu. But the fast-proliferating avian influenza infection is becoming a contender virus that could drive the next pandemic, one with a mortality rate that, if it spreads among humans, could make COVID-19 seem mild in comparison. The short answer: For the moment, the risk of consistent bird flu transmissions to - and between - humans is low, according to scientists. With the virus driving poultry shortages, killing droves of wild birds, and increasingly spilling over to mammals, the situation begs an overarching question: Could avian influenza evolve from an ecological disaster to a full-blown pandemic? But past human cases of H5N1 avian influenza have had a 53 percent mortality, according to the WHO. There have only been five human bird flu cases in the last year. But sequencing revealed something more sinister: a mutation that had enabled the first-ever large-scale case of direct mammal-to-mammal transmission of bird flu. Coming soon after another outbreak on the coast near Coruña, which left 27 seabirds sick or dead, avian influenza became a suspect. There, week by week, the mortality rate in a mink farm of 50,000 animals rose.
#Could there be a second lockdown movie
The story of these outbreaks is playing out like the opening shots of a pandemic movie - with the scene-stealer from last October in Galicia, Spain. Then in January, the World Health Organization (WHO) reported avian influenza in a young girl in Ecuador, the first such case ever in Latin America. In the United States, the list of wild mammals either killed by or culled over avian influenza outbreaks is growing: grizzly bears in Nebraska and Montana, a red fox in Montana, six skunks and raccoons in Oregon, a Kodiak bear in Alaska and more.
The rampant virus has jumped from Europe and Asia to North America - spreading shortly afterwards to bird populations in South and Central America.Īnd it is no longer restricted to birds.
It is a bloody trail: Avian flu has killed 15 million domestic birds and led to the culling of an unprecedented 193 million more since October 2021.
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