Bird flu virus could risk pandemic worse than Covid-19, France’s Institut Pasteur says
PARIS – The bird flu virus, which has been spreading among wild birds, poultry, and mammals, poses a significant threat of causing a pandemic more severe than Covid-19 if it mutates to transmit between humans, according to the head of France’s Institut Pasteur respiratory infections center. The highly pathogenic avian influenza, commonly known as bird flu, has already led to the culling of hundreds of millions of birds, disrupting food supplies and driving up prices, despite human infections remaining rare.
Dr. Marie-Anne Rameix-Welti, medical director at the Institut Pasteur’s respiratory infections center, expressed concern about the virus adapting to mammals, especially humans, and becoming capable of human-to-human transmission. She emphasized that such a virus would be a pandemic threat. While people have antibodies against common H1 and H3 seasonal flu, they lack immunity to the H5 bird flu affecting birds and mammals, similar to their lack of immunity to Covid-19. Unlike Covid-19, which primarily affects vulnerable individuals, flu viruses can also be deadly to healthy people, including children.
Dr. Rameix-Welti warned that a bird flu pandemic would likely be severe, potentially even more so than the pandemic experienced with Covid-19. She noted that while there have been cases of people infected by H5 bird flu viruses, including the H5N1 strain circulating among poultry and dairy cows in the US, these infections were often in close contact with infected animals. A recent development is the first-ever human case of H5N5 in the US state of Washington, where a man with underlying conditions died last week.
The World Health Organization (WHO) reported nearly 1,000 outbreaks of bird flu in humans between 2003 and 2025, primarily in Egypt, Indonesia, and Vietnam, with a 48% mortality rate. However, Dr. Gregorio Torres, head of the science department at the World Organisation for Animal Health, reassures that the risk of a human pandemic remains low. He advises that while preparedness is crucial, the current risk is still very low, and people can continue their daily activities without significant concern.
Despite the potential risks, Dr. Rameix-Welti acknowledges that the world is better prepared for a bird flu pandemic than it was before the Covid-19 pandemic. She highlights the availability of specific preventative measures, vaccine candidates, and stocks of antivirals that could be effective against avian influenza viruses.
