Cluster of oseltamivir-resistant 2009 pandemic influenza A (H1N1) virus infections on a hospital ward among immunocompromised patients--North Carolina, 2009.

Journal Article (Journal Article)

BACKGROUND: Oseltamivir resistance among 2009 pandemic influenza A (H1N1) viruses (pH1N1) is rare. We investigated a cluster of oseltamivir-resistant pH1N1 infections in a hospital ward. METHODS: We reviewed patient records and infection control measures and interviewed health care personnel (HCP) and visitors. Oseltamivir-resistant pH1N1 infections were found with real-time reverse-transcription polymerase chain reaction and pyrosequencing for the H275Y neuraminidase (NA) mutation. We compared hemagglutinin (HA) sequences from clinical samples from the outbreak with those of other surveillance viruses. RESULTS: During the period 6-11 October 2009, 4 immunocompromised patients within a hematology-oncology ward exhibited symptoms of pH1N1 infection. The likely index patient became febrile 8 days after completing a course of oseltamivir; isolation was instituted 9 days after symptom onset. Three other case patients developed symptoms 1, 3, and 5 days after the index patient. Three case patients were located in adjacent rooms. HA and NA sequences from case patients were identical. Twelve HCP and 6 visitors reported influenza symptoms during the study period. No other pH1N1 isolates from the hospital or from throughout the state carried the H275Y mutation. CONCLUSIONS: Geographic proximity, temporal clustering, presence of H275Y mutation, and viral sequence homology confirmed nosocomial transmission of oseltamivir-resistant pH1N1. Diagnostic vigilance and prompt isolation may prevent nosocomial transmission of influenza.

Full Text

Duke Authors

Cited Authors

  • Chen, LF; Dailey, NJM; Rao, AK; Fleischauer, AT; Greenwald, I; Deyde, VM; Moore, ZS; Anderson, DJ; Duffy, J; Gubareva, LV; Sexton, DJ; Fry, AM; Srinivasan, A; Wolfe, CR

Published Date

  • March 15, 2011

Published In

Volume / Issue

  • 203 / 6

Start / End Page

  • 838 - 846

PubMed ID

  • 21343149

Pubmed Central ID

  • PMC3307091

Electronic International Standard Serial Number (EISSN)

  • 1537-6613

Digital Object Identifier (DOI)

  • 10.1093/infdis/jiq124


  • eng

Conference Location

  • United States