Australia to Conduct Largest Wild-Bird Vaccination Experiment Ever Attempted
5,000 wild little penguins will be captured, microchipped, and vaccinated twice with an H5N2 bird-flu vaccine developed for chickens.
Australia is preparing to round up 5,000 wild little penguins, inject each of them twice with an avian-influenza vaccine, implant microchips, and release them back into the wild in what amounts to the largest wild-bird vaccination experiment ever attempted. In total, it will involve roughly 10,000 injections and 5,000 implanted microchips across a free-ranging wild population.
The vaccine being supplied for Australia’s protected bird program is a Zoetis H5N2 killed-virus vaccine developed for poultry, while the virus now circulating in Australian wildlife is H5N1. The product was developed for chickens, not wild penguins, and Australia has acknowledged that experience using these vaccines in non-poultry species is limited. Yet authorities are now scaling this intervention up to thousands of free-ranging animals.
The plan requires capturing the penguins, restraining them, injecting and microchipping them, releasing them, then finding and capturing them again several weeks later for a second dose. This is an unprecedented pharmaceutical intervention in a wild ecosystem.
The evolutionary consequences are especially concerning. These vaccines do not necessarily stop infection or viral replication, meaning H5N1 can continue circulating while encountering vaccine-induced immune pressure. Influenza mutates rapidly, and under those conditions variants better able to evade the vaccine response can gain a selective advantage and spread.
Continued circulation under vaccine pressure can also accelerate antigenic drift and favor vaccine-resistant strains, while co-infection with different influenza viruses creates opportunities for reassortment and novel variants. In wild penguins, these risks are even less predictable because there is little real-world experience with mass vaccination of free-ranging populations.
There is also a notable financial connection behind the supplier. Zoetis has received nearly $30 million in grants from the Bill & Melinda Gates Foundation, including funding involving poultry health, veterinary medicines, vaccines, and diagnostics. The Gates Foundation has also separately funded H5N1 avian-influenza vaccine development.
The scale of this should not be normalized. Five thousand wild penguins are being rounded up, double-vaccinated with a poultry-developed H5N2 influenza vaccine, permanently microchipped, and released back into an environment where H5N1 will continue circulating.
This is the largest wild-bird vaccination experiment ever attempted. It is a sweeping biological intervention with real evolutionary and ecological risks, and authorities are moving ahead despite limited species-specific evidence and no ability to know in advance what consequences they may be unleashing.
Epidemiologist and Foundation Administrator, McCullough Foundation
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Vaccinate Bill Gates first‼️
Remember the ostriich farm in Edgewater BC? Nothing is settled there a year after the diabolical slaughter of 300 ostriches! So disgusting!