With avian influenza A (H5N1) infecting more mammals than ever before — including U.S. dairy cattleopens in a new tab or window — infectious disease experts are paying close attention to whether current influenza antivirals would be effective should H5N1 adapt to humans.
All influenza viruses have extremely similar internal mechanisms for reproduction, William Schaffner, MD, of Vanderbilt University Medical Center in Nashville, Tennessee, and a spokesperson for the Infectious Diseases Society of America (IDSA), told MedPage Today. So if an antiviral works against one strain, it will also work on other strains, he said.
“Everything I’ve heard from the CDC and elsewhere … is that the antivirals that we have available today will work against H5N1. And that’s consistent with the effect of the antivirals against past avian influenza strains,” Schaffner said.
This includes neuraminidase inhibitors, such as oseltamivir (Tamiflu), zanamivir (Relenza), and peramivir (Rapivab), as well as the polymerase inhibitor baloxavir (Xofluza). While neuraminidase inhibitors interfere with the enzyme that allows a virus to cleave itself off an infected cell in order to spread, polymerase inhibitors interfere with replication at the level of messenger RNA.