Mutant Pandemic (H1N1) 2009 Virus, CME Activity | CDC EID

EID Journal Home > Volume 17, Number 4–April 2011

Volume 17, Number 4–April 2011
MEDSCAPE CME ACTIVITY
H275Y Mutant Pandemic (H1N1) 2009 Virus in Immunocompromised Patients
Medscape, LLC is pleased to provide online continuing medical education (CME) for this journal article, allowing clinicians the opportunity to earn CME credit.

This activity has been planned and implemented in accordance with the Essential Areas and policies of the Accreditation Council for Continuing Medical Education through the joint sponsorship of Medscape, LLC and Emerging Infectious Diseases. Medscape, LLC is accredited by the ACCME to provide continuing medical education for physicians.

Medscape, LLC designates this Journal-based CME activity for a maximum of 1 AMA PRA Category 1 Credit(s)TM. Physicians should claim only the credit commensurate with the extent of their participation in the activity.

All other clinicians completing this activity will be issued a certificate of participation. To participate in this journal CME activity: (1) review the learning objectives and author disclosures; (2) study the education content; (3) take the post-test and/or complete the evaluation at www.medscape.org/journal/eid; (4) view/print certificate.

Release date: March 23, 2011; Expiration date: March 23, 2012

Learning Objectives

Upon completion of this activity, participants will be able to:

•Distinguish clinical characteristics associated with treatment-resistant pandemic (H1N1) 2009
•Analyze outcomes of patients infected with treatment-resistant pandemic (H1N1) 2009
•Identify the rate of H275Y mutation development among patients with pandemic (H1N1) 2009 infection in the current study
•Evaluate the virology of treatment-resistant pandemic (H1N1) 2009

Medscape CME Editor
Karen L. Foster, Technical Writer/Editor, Emerging Infectious Diseases. Disclosure: Karen L. Foster has disclosed no relevant financial relationships.

Medscape CME Author
Charles P. Vega, MD, Associate Professor; Residency Director, Department of Family Medicine, University of California, Irvine. Disclosure: Charles P. Vega, MD, has disclosed no relevant financial relationships.

Authors

Disclosures: Christian Renaud, MD, MSc; Alexandre A. Boudreault; Jane Kuypers, PhD; Kathryn H. Lofy, MD; and Lawrence Corey, MD, have disclosed no relevant financial relationships. Michael J. Boeckh, MD, has disclosed the following relevant financial relationships: received grants for clinical research from Adamas, GlaxoSmithKline, and Roche; served as an advisor or consultant for Baxter HealthCare Pharmaceuticals and Roche/Genentech, Inc. Janet A. Englund, MD, has disclosed the following relevant financial relationships: received grants for clinical research from Adamas, ADMA, Chimerix, MedImmune Inc., and Novartis Pharmaceuticals Corporation; served as an advisor to US Attorney General, District of Alaska.
Mutant Pandemic (H1N1) 2009 Virus, CME Activity | CDC EID




EID Journal Home > Volume 17, Number 4–April 2011

Volume 17, Number 4–April 2011
Research
H275Y Mutant Pandemic (H1N1) 2009 Virus in Immunocompromised Patients

Christian Renaud, Alexandre A. Boudreault, Jane Kuypers, Kathryn H. Lofy, Lawrence Corey, Michael J. Boeckh, and Janet A. Englund

Author affiliations: Fred Hutchinson Cancer Research Center, Seattle, Washington, USA (C. Renaud, A.A. Boudreault, L. Corey, M.J. Boeckh, J.A. Englund); Seattle Children's Hospital, Seattle (C. Renaud, J.A. Englund); University of Washington, Seattle (J. Kuypers, L. Corey, M.J. Boeckh, J.A. Englund); and Washington State Department of Health, Shoreline, Washington, USA (K.H. Lofy)

Suggested citation for this article

Abstract
Most oseltamivir-resistant pandemic (H1N1) 2009 viruses have been isolated from immunocompromised patients. To describe the clinical features, treatment, outcomes, and virologic data associated with infection from pandemic (H1N1) 2009 virus with H275Y mutation in immunocompromised patients, we retrospectively identified 49 hematology–oncology patients infected with pandemic (H1N1) 2009 virus. Samples from 33 of those patients were tested for H275Y genotype by allele-specific real-time PCR. Of the 8 patients in whom H275Y mutations was identified, 1 had severe pneumonia; 3 had mild pneumonia with prolonged virus shedding; and 4 had upper respiratory tract infection, of whom 3 had prolonged virus shedding. All patients had received oseltamivir before the H275Y mutation was detected; 1 had received antiviral prophylaxis. Three patients excreted resistant virus for >60 days. Emergence of oseltamivir resistance is frequent in immunocompromised patients infected with pandemic (H1N1) 2009 virus and can be associated with a wide range of clinical disease and viral kinetics.

The development of antiviral drug resistance in influenza viruses affects patient care. Concerns for worldwide spread of resistant virus are growing (1). Approximately 300 patients with oseltamivir-resistant pandemic (H1N1) 2009 virus have been reported to the World Health Organization, with the complexity of treatment and consequences of infection well described (2–5). Millions of oseltamivir doses have been stockpiled worldwide, representing one of the major interventions to contain and mitigate the impact of influenza and potentially offer treatment to large numbers of patients (6,7). The efficacy and cost of pharmacologic interventions to contain oseltamivir-resistant virus are of major concern.

Most resistant pandemic (H1N1) 2009 viruses have been detected in immunocompromised patients who received neuraminidase inhibitors, and all but 1 had the H275Y neuraminidase mutation (2). This mutation had already been observed before the pandemic (H1N1) 2009 outbreak, for example, it was detected worldwide in healthy patients who had not received antiviral drugs and were infected with seasonal (H1N1) virus during the 2008–09 influenza season (8). Efforts are under way to characterize and detect the H275Y mutation, but data on clinical impact and viral fitness (i.e., replicative capacity in vitro and in vivo that can further be correlated with transmissibility and virulence) associated with this mutation are still needed. We describe in detail the clinical features, treatment, outcomes, and virologic data associated with infection caused by pandemic (H1N1) 2009 virus with H275Y mutation in immunocompromised patients.

full-text:
Mutant Pandemic (H1N1) 2009 Virus | CDC EID

Suggested Citation for this Article
Renaud C, Boudreault AA, Kuypers J, Lofy KH, Corey L, Boeckh MJ, et al. H275Y mutant pandemic (H1N1) 2009 virus in immunocompromised patients. Emerg Infect Dis [serial on the Internet]. 2011 Apr [date cited].
http://www.cdc.gov/EID/content/17/4/653.htm

DOI: 10.3201/eid1704.101429


Comments to the Authors
Please use the form below to submit correspondence to the authors or contact them at the following address:

Janet A. Englund, Children's Hospital and Regional Medical Center, 4800 Sand Point Way NE #8G-1, Seattle, WA 98105 USA; email: janet.englund@seattlechildrens.org