CDC slightly increases risk bird flu could cause a pandemic in latest assessment
The Centers for Disease Control and Prevention issued a new risk assessment of the H5N1 bird flu virus circulating in dairy cows on Friday, increasing slightly its estimate of the chance it poses of triggering a pandemic.
The new assessment, developed using the CDC’s influenza risk assessment tool or IRAT, gauged the risk the virus might someday cause a pandemic at 5.79, up from a previous score of 5.12 from an assessment of a related virus conducted in April 2023. Both numbers are within what the CDC tool terms a “moderate” risk of 4.0 to 7.9. Some swine influenza viruses and the H7N9 bird flu virus have scored higher than this version of H5N1 using the IRAT process.
