Prolonged excretion of amantadine-resistant influenza a virus quasi species after cessation of antiviral therapy in an immunocompromised patient.
Phenotypic and molecular studies were conducted to characterize multiple influenza A isolates recovered from an immunocompromised patient who died of viral and fungal pneumonitis. The recovery of amantadine-resistant isolates was correlated with the detection of 2 drug-resistant M2 variants (codons 27 and 31) in combination with a wild-type virus. The mutant viruses persisted within the viral population in variable proportions >1 month after cessation of antiviral therapy. These results confirm animal studies reported elsewhere regarding the genetic stability of influenza M2 mutants and their potential for transmission in humans.
Boivin
Guy
G
Research Center in Infectious Diseases, Centre Hospitalier de l'Université Laval, Sainte-Foy, Quebec, Canada. Guy.Boivin@crchul.ulaval.ca
Goyette
Nathalie
N
Bernatchez
Harold
H
D000547:Amantadine / Q000494:pharmacology* / Q000627:therapeutic use; D000998:Antiviral Agents / Q000494:pharmacology* / Q000627:therapeutic use; D004352:Drug Resistance, Microbial / Q000235:genetics*; D005838:Genotype; D006801:Humans; D016867:Immunocompromised Host; D009980:Influenza A virus / Q000187:drug effects / Q000235:genetics*; D008297:Male; D008875:Middle Aged; D009154:Mutation; D010641:Phenotype; D016133:Polymerase Chain Reaction
D000998:Antiviral Agents; D000547:Amantadine