Post by Nadica (She/Her) on Jun 14, 2024 8:31:27 GMT
Drug-resistant "dual mutant" flu strains now being tracked in U.S., CDC says - CBS News - Published June 12, 2024
At least two human cases of the new so-called "dual mutant" strains of H1N1 influenza have been detected in U.S. patients, the Centers for Disease Control and Prevention said Wednesday, with genetic changes that could cut the effectiveness of the main flu antiviral that hospitals rely on.
An analysis of the new H1N1 flu viruses with these two concerning mutations – which scientists call I223V and S247N, describing changes to key surface proteins of the virus – was published this week in the agency's Emerging Infectious Diseases journal.
It follows a report by scientists from Hong Kong who first tested the mutations. Their lab experiments, published in March, found the two mutations appeared to raise H1N1's resistance to the flu treatment oseltamivir, commonly sold under the brand Tamiflu by drugmaker Roche.
It is unclear how much the mutations could cut the real-world effectiveness of oseltamivir. The laboratory tests found the mutated viruses were up to 16 times less sensitive to the antiviral, a smaller dropoff than in some previous worrying mutations.
"These mutated viruses retained sensitivity to other anti-influenza medications, including a newer one, baloxavir marboxil. There are no immediate implications to change decisions for clinical care," a CDC spokesperson said in an emailed statement. The spokesperson said that flu vaccination can still offer protection against viruses with these mutations.
Keywords: Influenza, H1N1, Mutation,
At least two human cases of the new so-called "dual mutant" strains of H1N1 influenza have been detected in U.S. patients, the Centers for Disease Control and Prevention said Wednesday, with genetic changes that could cut the effectiveness of the main flu antiviral that hospitals rely on.
An analysis of the new H1N1 flu viruses with these two concerning mutations – which scientists call I223V and S247N, describing changes to key surface proteins of the virus – was published this week in the agency's Emerging Infectious Diseases journal.
It follows a report by scientists from Hong Kong who first tested the mutations. Their lab experiments, published in March, found the two mutations appeared to raise H1N1's resistance to the flu treatment oseltamivir, commonly sold under the brand Tamiflu by drugmaker Roche.
It is unclear how much the mutations could cut the real-world effectiveness of oseltamivir. The laboratory tests found the mutated viruses were up to 16 times less sensitive to the antiviral, a smaller dropoff than in some previous worrying mutations.
"These mutated viruses retained sensitivity to other anti-influenza medications, including a newer one, baloxavir marboxil. There are no immediate implications to change decisions for clinical care," a CDC spokesperson said in an emailed statement. The spokesperson said that flu vaccination can still offer protection against viruses with these mutations.
Keywords: Influenza, H1N1, Mutation,