Scientists say the H5 avian influenza strain poses a catastrophic global risk if it mutates to spread between humans — but stress that the current probability remains low.
A leading French research institute is warning that the world could face a pandemic more severe than Covid-19 if a highly pathogenic avian influenza virus gains the ability to spread efficiently between people. The alert comes as global health systems remain stretched from years of crisis, and as climate change, wildlife migration, and industrial farming increase opportunities for viral spillover.
Dr. Marie-Anne Rameix-Welti, medical director of the Center for Respiratory Infections at the Pasteur Institute in Paris, said her team is closely monitoring H5 avian flu strains circulating in wild birds, poultry, and mammals. “If a virus adapts to mammals — especially humans — and becomes capable of human-to-human transmission, that virus would be a pandemic virus,” she said.
The Pasteur Institute played a central role in the early Covid-19 response, creating one of the first diagnostic tests and sharing the protocol with the World Health Organization. Its latest warning arrives amid a wave of disruptive bird flu outbreaks that have led to the culling of hundreds of millions of poultry worldwide, distorting food supply chains and pushing up global prices.
While human infections remain rare, the dangers are significant. People typically have antibodies against common seasonal flu strains such as H1 and H3 — but not against H5 viruses, which infect birds and some mammals. Unlike Covid-19, which disproportionately affects vulnerable groups, the flu virus “can harm healthy people, including children,” Rameix-Welti noted.
The concerns follow several recent human cases linked to close contact with infected animals, including H5N1 in U.S. dairy cattle and the first H5N5 human case reported in Washington state this month, in which the patient — who had underlying health conditions — died. From 2003 to 2025, nearly 1,000 human cases of H5 infections have been reported globally, almost half of them fatal.
Even so, global health authorities urge caution, not panic. Dr. Gregorio Torres, chief scientist at the World Organization for Animal Health, said the probability of the virus evolving into a human-transmissible pandemic strain is “still very low.” He added: “You can still walk in the woods, eat chicken and eggs, and enjoy life.”
Researchers emphasize that the world is better positioned than it was in early 2020. Unlike Covid-19, vaccine candidates against H5 viruses already exist, manufacturing processes are well established, and antiviral stockpiles are available.
Still, the Pasteur Institute’s warning underscores a broader reality: as zoonotic risks rise, so must global preparedness. Whether the world can translate hard-won lessons from Covid-19 into faster, more coordinated action may determine how it confronts the next potential pandemic threat.
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Source: Vietnam Insider