Vaccine and Infectious Disease Division

Detecting drug-resistant H1N1 influenza

Strains of influenza that are resistant to standard anti-flu drugs have been a major problem in some flu seasons, especially among immunocompromised populations.  While resistant strains of the novel H1N1 influenza are rare to date, there have been reports of H1N1 cases resistant to oseltamivir (sold under the brand name Tamiflu in the U.S.).  In the clinical setting, rapid and inexpensive methods are needed to accurately diagnose oseltamivir-resistant strains of H1N1, in order to provide the proper care for these patients.  To date, all resistant strains isolated carry the same single mutation, H275Y in the neuraminidase gene. 

VIDD postdoctoral fellow Dr. Christian Renaud, along with staff scientist Dr. Jane Kuypers and co-director Dr. Larry Corey, have developed a type of PCR technique to quickly identify strains of H1N1 carrying this mutation.  Their method, developed in the Molecular Diagnostic Laboratory, is now available for clinical testing on specimens positive for novel H1N1 influenza.  Tracking resistance and mutant viruses will be part of routine care for immunocompromised patients.

Renaud C, Kuypers J, Corey L.  Diagnostic accuracy of an allele-specific reverse transcriptase-PCR assay targeting the H275Y oseltamivir resistant mutation in 2009 pandemic influenza A/H1N1 virus.  J Clin Virol. 2010 Sep;49(1):21-5.