A dolphin in Florida has died after being infected with bird flu (H5N1) according to a new study published just days after the World Health Organization declared avian influenza a global zoonotic pandemic.
A new study published in April 2024 reveals that, in 2022, a dolphin died from bird flu in the United States. It marks the first cetacean ever recorded to be infected with highly pathogenic avian influenza in North America. Scientists who authored the study now fear the spread of bird flu in cetaceans “could be catastrophic.”
Scientists were notified of a bottlenose dolphin in distress in March 2022, who unfortunately died by the time rescuers arrived. A necropsy found bird flu, H5N1, was in the dolphin’s brain and lungs, having mutated to become 18 times more resistant to current drug treatments. According to the necropsy, the majority of the virus was found in the dolphin’s brain, the tissue that covers the brain, and the spinal cord.
Before the dolphin passed away, a local bird die-off linked to bird flu occurred, though the flu causing local bird outbreaks didn’t have the same genetics as the one that killed the dolphin. At this time, scientists don’t know where this particular strain of bird flu came from.
This specific mutation has notably killed sea lions in Peru and Chile and both harbor and gray seals in New England and Canada, and other iconic species have since died from bird flu as the virus spread around the globe. A polar bear who died in Alaska in October 2023 from bird flu was also the first confirmed case of H5N1 in the species anywhere in the world. A king penguin was also found dead of suspected bird flu and elephant seals have been dying en masse in the Antarctic from the disease.
Liz Cabrera Holtz, Campaign Manager for World Animal Protection US, stated:
“Animals are the first to pay the price when politicians refuse to hold animal agriculture corporations responsible. But the death of this dolphin from the avian flu underscores that it’s not just farmed animals who suffer. Factory farming puts all of us at risk of the next pandemic. We have to change our food system now.”
Bird flu has been wreaking havoc on wild and farmed animals since 2020 and was first detected in North America in 2021. Since then, the World Organization for Animal Health (WOAH) noted that approximately 485 bird species and 37 mammal species have been infected with avian influenza. Most recently, 33 dairy herds in the United States have been infected with avian influenza, though experts believe that it could be much more widespread than originally thought. The World Health Organization—which recognizes the links between animals and human pandemics—recently declared avian influenza a global zoonotic pandemic.
Like animals on factory farms, captive wild animals are often more susceptible to infections due to the constant stress in captivity. Wildlife farms, whether breeding animals to be killed or to be sold for a lifetime in captivity, can be a major cause of zoonotic disease outbreak.
Now that we know dolphins in the wild can contract highly pathogenic avian influenza, it’s clear that captive dolphins are at risk of contracting the virus—among other diseases that can be transmitted to other animals or humans.
While the dolphin infected with avian flu was in the wild, captive dolphins forced to interact with people pose a risk to human health, while members of the public can transmit diseases to the cetaceans through this contact.
In fact, researchers from the University of California, Davis (UC Davis) highlighted the potential risks that humans are exposed to due to close contact with marine mammals. Respiratory diseases were reported in nearly a fifth of marine mammal workers, including diseases such as tuberculosis, leptospirosis, brucellosis, and a skin rash or reaction. Similarly to workers in factory farms, workers in the captive animal entertainment industry are in a high-risk group for infection and are considered an “occupational hazard.”
Diseases from marine mammals are difficult to treat and diagnose, with some of the transmissible diseases being life-threatening. Dolphinariums and marine mammal entertainment venues, like SeaWorld and Miami Seaquarium, that allow direct contact interactions (such as swim or “trainer for a day” experiences) with dolphins are putting the public at risk for disease transmission.
However, dolphins are also susceptible to diseases transmissible by humans—in both captivity and the wild. In 2013, human measles was responsible for the die-off of bottlenose dolphins along the East Coast, with 333 dead or sickly dolphins washing up along the shore. This mass die-off was over nine times the historical average. Bottlenose dolphins can catch the disease through direct contact with infected dolphins or respiratory particles (from the air they breathe).
In 2020, researchers noted that 15 marine species, including whales, dolphins, seals, and sea otters, were susceptible to COVID-19. In areas where wastewater is discharged, cetaceans could contract the virus through their eyes, blowholes, or the insides of their mouths depending on the amount of exposure, but marine mammal scientist Naomi Rose told Mongabay News (at the time) that captive cetaceans were at higher risk of contracting COVID-19 through close contact with infected caretakers or the public.
Rose stated:
“[D]iseases may start jumping from wildlife to humans and vice versa in the future, more and more. We need to be aware of this possibility and mitigate the risk — rather than continue on as we have, assuming animal diseases aren’t our problem and vice versa.”
While there have been no confirmed cases of COVID-19 in cetaceans, both belugas and dolphins have been infected with related gamma coronaviruses in the past.
Whether it’s bird flu or COVID-19, the way we interact with animals needs to change if we want to safeguard animals and public health. Zoonotic diseases cause an estimated two million human deaths annually and of the zoonotic diseases found in human populations between 1940 and 2004, 72% came from wildlife origin, according to World Animal Protection’s Bred for Profit report.
COVID-19 was responsible for the slaughter of more than 14 million mink on Danish fur farms due to fears of a mutated virus. Bird flu alone has killed over 80 million birds on factory farms in the United States and over 500,000 seabirds have died from the virus.
The spread of H5N1 avian influenza, which has hit Europe and the Americas hard since 2021, has been described as “the largest-ever” continuous outbreak of the disease.
Because bird flu is so infectious, it spreads rapidly throughout bird populations and the conditions on factory farms create a perfect breeding ground for viruses to evolve and spread rapidly. Factory farms also increase the likelihood that a single outbreak can quickly result in the suffering and death of tens of millions of individual, sentient chickens, ducks, turkeys, and geese raised for food products.
Transmissible through saliva, mucous, or feces, wild birds can easily be infected if they’re around factory farms where birds have been exposed to the disease—especially if the wild birds are scavengers who consume the bodies of birds who have died before reaching the slaughterhouse. This leads to migratory birds being infected and then spreading the disease to wild and farmed animals throughout the globe as they travel.
Could bird flu become the next human pandemic? If we don’t change the way we interact with all animals and end wildlife farming and factory farming, it might be. At this time, the virus is not human-to-human transmissible, but is highly contagious among mammals and has infected two people who were in close contact with infected farmed animals.
The FDA, USDA, CDC, and the Biden Administration are currently monitoring the situation, though experts are warning that the government is making the “same mistakes with bird flu” as was done with the COVID-19 pandemic.
In order to prevent the next global pandemic and better protect animals, humans, and our planet, World Animal Protection is calling for an end to wildlife exploitation and factory farming globally.
Please take action today by urgently sending a letter to your federal legislators urging them to co-sponsor the Farm System Reform Act (FSRA), which would ban factory farming in the United States.