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• ‘A genuine wildlife emergency’: everything you need to know about the arrival of H5 bird flu in Australia | Environment | The Guardian

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A deadly strain of bird flu, known as H5 bird flu, has arrived on the Australian mainland.

The federal agriculture minister, Julie Collins, this weekend confirmed that a brown skua – that had been found sick in Western Australia – had died from the H5N1 virus. The skua is a wild migratory bird.

A second bird, a sick giant petrel found nearby, was also likely infected.

Australia’s run as the only continent free of the virus has now ended. H5 bird flu has killed millions of birds and thousands of marine mammals since it began spreading across the globe in 2021.

A Pitt-led study reveals the biology of why the disease looked so different when it made the leap to cows and offers a framework for spotting its next new guise more quickly.

Home / News / How Bird Flu Hid in Dairy Cattle

Photography by Rayni Shiring, University of Pittsburgh

When H5N1 bird flu first began infecting U.S. cattle in early 2024, diagnosis was elusive, because in cows, the disease looked completely different. Instead of affecting the lungs, as H5N1 does in other mammalian species, it caused severe infection in the cows’ udders, largely sparing the lungs.  

A study by University of Pittsburgh School of Public Health researchers published June 19 in Science Advances provides the first mechanistic explanation for this peculiar new guise for H5N1, which now affects more than 100 bird and mammal species globally. The study also establishes a new way to help scientists spot bird flu’s next surprise move more quickly, saving precious time in mounting public-health measures to stem the spread. 

The disease first appeared in dairy cattle along the Texas Panhandle as stubborn cases of severe, necrotizing mastitis, a painful inflammatory condition that damages tissues in the mammary glands.  

“Mastitis is a classic disease in milk-production animals, and veterinarians were dutifully looking to all the usual suspects for the source, like bacterial pathogens,” said senior author Suresh Kuchipudi, professor and chair, Department of Infectious Diseases and Microbiology, School of Public Health, at Pitt. “When the real culprit turned out to be bird flu, everyone in the field was caught completely by surprise. We hadn’t even remotely considered that cattle could be a host for H5N1.”  

In the weeks before the virus was identified, it moved from herd to herd, sickening the cattle—and contaminating their environments.  

“If a cow is infected, it sheds a lot of virus into the milk,” said Kuchipudi. “This raised concerns about occupational risk for farm workers. Also, there is a habit of feeding raw milk to domestic pets, like cats, and there have been instances of cats dying, which we studied previously.” He stressed that fortunately, pasteurization is effective at killing the virus, underlining the importance of avoiding raw milk. 

Kuchipudi has been studying influenza viruses for his entire career, with a particular focus on how receptor biology determines which species—and which tissues—can be infected. Typically, such studies involve staining cells for the presence of receptors that are known to work in a lock-and-key relationship with influenza, a subset of sugar-based molecules known as glycans.  

In initial studies by other groups, such experiments suggested that flu‑related glycan receptors were present in the noses, tracheas and lungs of cows. The fact that the animals were nonetheless not developing respiratory infections told the team there was more to the story.  

“Glycan biology is very complex,” said Kuchipudi. “We realized that, to understand what was really going on, we would need to use more innovative technologies and map out the finely detailed architecture that enables the virus to bind to cells.” Kuchipudi collaborated on the study with Harvard Medical School’s Lauren E. Pepi, an expert in the methodology for comprehensively cataloging the entirety of glycan structures, dubbed glycomics.   

Using a multimodal approach that combined binding experiments, staining methods and ultrahigh‑resolution imaging, the team revealed that not all glycan receptors were functioning the same in animals infected with bird flu. Only a particular subtype, known as N‑linked sialic acid receptors, could bind to H5N1. These receptors were virtually absent in cow airway tissue, but pervasive in udders, making them a “perfect breeding ground for the virus,” Kuchipudi said. 

The research provides a framework other scientists can use to potentially predict not just whether H5N1 can jump to new hosts, but also how.  

“We can preemptively screen different species and different tissues within them for susceptibility,” said Kuchipudi. “For example, would they exhibit respiratory symptoms? Would they show only mastitis, as in cows? Or would they show neurological disease, as our team has shown in cats? The lessons learned could potentially help prevent us from being caught by surprise again.”  

Other authors on the study were Surabhi Srinivas, Shubhada K. Chothe, Santhamani Ramasamy, Sougat Misra, Noel Chandan Nallipogu and Lindsey LaBella, all of Pitt; Yin-Ting Yeh, of The Pennsylvania State University; May Wang, of Harvard University; and Heidi L. Pecoraro and Brett T. Webb, of North Dakota State University. 

This research was supported by Pitt Public Health, and the U.S. Department of Agriculture’s National Institute of Food and Agriculture (FP00039373/AWD00010780). 

How Bird Flu Hid in Dairy Cattle – Health Sciences | University of Pittsburgh

By Reuters

June 19, 20261:11 AM PDTUpdated 13 hours ago

Australia, last continent without H5 bird flu, detects first suspected case | Reuters

SYDNEY, June 19 (Reuters) – Australia has detected its first suspected mainland case of H5N1 bird flu in a remote part of the country’s ​southwest, authorities said on Friday.

A migratory sea bird known as a brown ‌skua found in Western Australia’s Cape Le Grand National Park tested positive for avian influenza, and further testing is being conducted to confirm the strain, said state Agriculture Minister Jackie Jarvis.

Keep up with the latest medical breakthroughs and healthcare trends with the Reuters Health Rounds newsletter. Sign up here.

“We ​are taking the suspected case of H5 bird flu seriously,” Jarvis said. “If ​this is confirmed H5 bird incursion, there will be a rapid ⁠and coordinated national response.”

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The virulent strain of H5 bird flu has spread through ​wild bird and mammal populations since 2021, killing millions, infecting poultry and dairy farms ​and even some farmworkers.

Australia is the only continent without a confirmed mainland case of the deadly strain. H5 was confirmed on Heard Island, a sub-Antarctic Australian territory in late 2025.

The country has been ​preparing for the arrival of H5N1 bird flu by tightening biosecurity at farms, ​testing shore birds for disease, vaccinating vulnerable species and war-gaming response plans.

“While, if confirmed, this would ‌obviously ⁠be a very concerning development, Australia has spent the past few years preparing for this likelihood,” Environment Minister Murray Watt said in a statement.

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Results confirming whether the now-deceased brown skua had contracted H5 bird flu is expected on Saturday, Jarvis said.

She added that ​another sick bird, a ​giant petrol, was ⁠also found in the same area and is being tested for influenza.

Wayne Boardman, a wildlife veterinarian and associate professor at Adelaide ​University, said the virus could devastate Australia’s native wildlife.

“This strain ​of bird ⁠flu has caused huge die-offs of birds and sea mammals,” he said.

“My concerns are that if the H5N1 avian flu virus is confirmed, it will pose a huge ⁠risk ​to some of our more endangered shorebirds, some of ​our coastal raptors, and our precious, unique, endemic and endangered Australian sea lions, whose population is precarious.”

The whale sustained some injuries during the ordeal, but should recover.

Laura Baisas

Published Jun 16, 2026 10:55 AM EDT

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A team from the Center for Coastal Studies (CCS) untangled a young humpback whale (Megaptera novaeangliae) off the coast of Massachusetts. The whale was caught in fishing gear in the Stellwagen Bank National Marine Sanctuary east of Boston between Cape Ann and Cape Cod. Stellwagen Bank is a hotspot for humpbacks and other whales, who feed on the plentiful plankton and fish in the bank’s rich waters during the spring and summer.

The whale was freed by CCS’ Marine Animal Entanglement Response (MAER) team, who is trained to safely disentangle whales. CCS has freed over 200 large whales and other marine life from entanglements since 1984.

Recreational boaters in the area reported a relatively small whale struggling in the gear’s buoy line. Once the MAER team was on the scene, they found the humpback with ropes wrapped around the base of its tale. The ropes were essentially keeping the whale anchored in place and the whale spent most of its time at the surface.

The process was further complicated by the weather. With winds forecasted to significantly increase, the team had to work quickly and assess the animal’s conditions and attempt disentanglement. 

“Approaching from behind, the team used a hook-shaped knife at the end of a 30-foot pole to make a series of cuts to the wraps of rope at its tail, eventually freeing the whale,” CCS wrote in a statement. 

Once freed, the whale stayed fairly still at the surface, and the team remained with the humpback until it began to move again. The whale sustained some injuries due to the entanglement, but the team believes that it will recover. The CCS Humpback Whale Studies Program is working to identify the whale using their database. 

According to the CCS, this rescue is an example of what can happen when several organizations work together. The boaters reported the sighting to the United States Coast Guard, who then contacted the NOAA Fisheries and CCS hotlines. The Massachusetts Environmental Police also responded, as they were in the area when the call came in and stayed with the whale until the MAER rescue team arrived. TowBoatUS also overheard the report and offered to stand by and assist as needed

“It was really great that so many people and institutions helped out in this case. The whale has a much better prognosis due to that,” MAER Assistant Director Bob Lynch said in a statement.

A whale first responder from over 5,000 miles away also assisted. Maria Harvey from the Hawaiian Islands Humpback Whale National Marine Sanctuary happened to be working with the CCS team as part of an ongoing partnership. “It was an honor to help this whale and great to continue the collaboration between our teams,” Harvey added.

Over the past month, this particular whale has been spotted several times by whale watchers in the area. It has several deep but healing wounds from prior entanglements. The International Whaling Commission (IWC) estimates that over 300,000 whales and dolphins die every year due to bycatch and entanglement in fishing gear. 

According to CCS, their disentanglement work is supported in part by grants from the National Marine Fisheries Service (NMFS), the Massachusetts Division of Marine Fisheries (MA-DMF), the Massachusetts Environmental Trust, and private foundations and donors. All disentanglement activities are conducted under a federal permit authorized by NOAA.