Even after it develops resistance to antiviral medication Tamiflu (oseltamivir), H7N9 — an avian strain of influenza A that emerged in China last spring — can still generate prolonged, severe infections and poor clinical outcomes, according to open-access results from researchers at the Icahn School of Medicine at Mount Sinai.
While it is not uncommon for influenza viruses to develop genetic mutations that increase their resistance to anti-flu drugs, that mutation typically weakens the virus’ ability to replicate and to spread from one person to another, according to researchers.
“Our study underscores the need to develop a bigger arsenal of antiviral drugs and vaccines, which will allow us to outsmart the influenza virus,” said said lead investigator Nicole Bouvier, MD, Assistant Professor of Medicine, Infectious Diseases at the Icahn School of Medicine at Mount Sinai. “Researchers at Mount Sinai are actively engaged in identifying new targets for drug therapy and are working to develop a universal vaccine that will prevent multiple strains of influenza.”
During the Chinese outbreak, researchers identified differences in the behavior of H7N9 and other avian influenza strains that can infect humans, Investigators found that a drug-resistant H7N9 virus retained its ability to replicate in human respiratory cells and was comparable to a non-resistant form of the virus in producing severe illness in animal models.
They also discovered that, although H7N9 appears to have a limited ability to spread readily from human to human, transmissibility in animal models was comparable between drug-susceptible and drug-resistant strains.