An international coalition of leading virologists has warned that the United States must intensify its response to the year-long H5N1 bird flu outbreak to avert a potential pandemic, according to a report by the Financial Times. The Global Virus Network, comprising scientists from over 40 countries, sounded the alarm on Tuesday, citing the rising threat posed by the virus’s spread across all 50 US states.
In an article published in The Lancet Regional Health-Americas, the experts emphasized the historically high human mortality rate associated with H5N1 and urged global governments to bolster surveillance, enforce stricter biosecurity measures, and prepare for possible human-to-human transmission.
“Currently, the risk for humans not handling infected animals is low, because the viruses are not able to transmit between people,” said Professor Marion Koopmans of the Netherlands’ Erasmus Medical Centre, a co-author of the paper. “But that can change abruptly if the virus picks up mutations, which can happen if it continues to circulate in mammals.”
Since March 2024, the H5N1 virus has devastated US agriculture, infecting over 1,000 dairy herds and decimating tens of millions of poultry birds. At least 70 human cases have been confirmed, including one fatality in Louisiana, according to the Centers for Disease Control and Prevention (CDC).
The Financial Times reports that both the Biden and Trump administrations have faced criticism for insufficient action to contain the outbreak. Scientists warn that continued circulation of the virus heightens the risk of genetic mixing with other animal or human influenza viruses, potentially creating a highly transmissible strain. In a worrying development, the UK recently reported the first known case of H5N1 infection in a sheep.
The virologists stressed the need for rapid sharing of US genomic sequencing data and metadata, warning that current findings show “ongoing mutations” and infections among mammals, including sea lions and mink. If genetic material from the virus mixes with swine or human flu strains, it could significantly raise the pandemic threat.
Compounding concerns is what scientists describe as political interference. The Trump administration has been accused of curbing communication by public health agencies like the CDC and restricting research in fields including vaccines and climate science. The Global Virus Network condemned these moves, stating, “We deplore restrictions placed on CDC and other public health communications consequent to the current US political climate. This hampers the effectiveness of full implementation of protective public health measures.”
The scientists also criticized the patchy rollout of bird flu testing, highlighting that inconsistent milk testing across states undermines national surveillance efforts. The ongoing outbreak has had economic consequences as well, with egg prices in the US hitting all-time highs due to the impact on poultry production.
