Failure to Detect Oseltamivir Resistance by Rolling Circle Amplification and Sequencing Following Use in an Influenza A (H3N2) Outbreak at an Aged Care Facility
Alexander Rosewell1,2, Bin Wang3, Nitin K Saksena3, C Raina MacIntyre1, Richard Lindley4, Clayton Chiu1, Carol Shineberg1, Elizabeth Clarke1, Ken McPhie5, V Mala Ratnamohan5, Robert Booy1, Dominic E Dwyer5,*
- Corresponding Author:
- Dr. Dominic E Dwyer BSc (Med), MB BS, MD,
FRACP, FRCPA, Centre for Infectious Diseases and Microbiology Laboratory Services,
ICPMR, Westmead Hospital, Westmead, NSW,
Phone : +612 9845 6255,
Fax : +612 9633 5314,
E-mail : [email protected]
Received Date: October 15, 2009; Accepted Date: November 04, 2009; Published Date: November 05, 2009
Citation: Rosewell A, Wang B, Saksena NK, MacIntyre CR, Lindley R, et al. (2009) Failure to Detect Oseltamivir Resistance by Rolling Circle Amplification and Sequencing Following Use in an Influenza A (H3N2) Outbreak at an Aged Care Facility. J Antivir Antiretrovir 1: 056-061. doi:
Copyright: © 2009 Rosewell A, et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
Background: The recent worldwide emergence of increasing oseltamivir resistance to influenza A H1N1 may have important implications for influenza prevention and control. Objectives: To assess oseltamivir use, the emergence of resistance and the outcome of an influenza A H3N2 outbreak. Patients/Methods: Following identification of an influenza outbreak through active surveillance, the investigators offered treatment and prophylaxis with oseltamivir to both Aged Care Facility (ACF) residents and staff. The investigators conducted genotypic sensitivity testing using sequencing and rolling circle amplfication for known oseltamivir resistance mutations. Results: An influenza A H3N2 outbreak affecting an ACF with 90 residents and 79 staff was identified 6 days after the initial case. Oseltamivir prophylaxis was commenced on day 7. The overall attack rate was 10%, with 13 of 92 residents and 4 of 79 staff infected.There was no evidence of the development of genotypic resistance, even at low levels, to oseltamivir in patients tested whilst on treatment or prophylaxis. Conclusions: There was no clinical or genotypic evidence of oseltamivir resistance, an important observation in the context of recent reported antiviral resistance in other influenza A subtypes.