A mutated bird flu virus capable of spreading between humans could trigger a pandemic more severe than COVID-19, a leading French virologist has warned. This stark assessment comes as the highly pathogenic avian influenza continues to devastate bird populations globally and shows increasing signs of infecting mammals.
Why a Bird Flu Pandemic Would Be Severe
Dr. Marie-Anne Rameix-Welti, the medical director of the respiratory infections centre at France's renowned Institut Pasteur, explained the core concern to Reuters. The fear is that the virus will adapt to mammals and then to humans, gaining the ability for sustained human-to-human transmission. Unlike COVID-19, which predominantly affected vulnerable populations, influenza viruses have a historical track record of causing severe illness and death in healthy individuals, including children.
Compounding the threat is a critical lack of pre-existing immunity in the human population. "People have antibodies against common H1 and H3 seasonal flu, but none against the H5 bird flu affecting birds and mammals, like they had none against COVID-19," Dr. Rameix-Welti stated. This means our immune systems would be largely unprepared for an H5-type virus.
Current Risk and Historical Context
While the potential consequences are grave, international health authorities currently assess the immediate risk of a human pandemic as low. Gregorio Torres, head of the Science Department at the World Organisation for Animal Health, urged a balanced perspective. "We need to be prepared to respond early enough. But for the time being, you can happily walk in the forest, eat chicken and eggs and enjoy your life. The pandemic risk is a possibility. But in terms of probability, it’s still very low," he told Reuters.
Human infections with H5 bird flu viruses, including the H5N1 strain currently circulating in U.S. poultry and dairy cows, have occurred. However, these cases have typically been in people with close contact to infected animals. The World Health Organization (WHO) reports that between 2003 and 2025, there have been nearly 1,000 human outbreaks, primarily in Egypt, Indonesia, and Vietnam, with a concerning fatality rate of 48%.
In a recent development, a man in the U.S. state of Washington with underlying health conditions died after contracting a first-ever human case of H5N5.
The World Is Better Prepared Now
Despite the alarming warnings, there is a silver lining. Dr. Rameix-Welti emphasized that the world is in a much stronger position to respond than it was before the COVID-19 pandemic. "The positive point with flu, compared to COVID, is we have specific preventative measures in place. We have vaccine candidates ready and know how to manufacture a vaccine quickly," she said.
Furthermore, global health systems have stockpiles of specific antiviral drugs that are expected to be effective against avian influenza viruses. The Institut Pasteur, which was among the first European labs to develop and share COVID-19 detection tests globally, represents the kind of established scientific infrastructure that could be rapidly mobilized.
The key takeaway is a call for vigilant monitoring and preparedness, rather than panic. While the probability of a bird flu pandemic remains low for now, its potential severity makes robust surveillance and rapid response planning an international priority.
