We describe the first confirmed person-to-person transmission of oseltamivir-resistant pandemic influenza A(H1N1) 2009 virus that occurred in a hematology unit in the United Kingdom. Eleven cases of (H1N1) 2009 virus infection were identified, of which, ten were related as shown by sequence analysis of the hemagglutinin and neuraminidase genes. H275Y analysis demonstrated that 8 of 10 case patients had oseltamivir-resistant virus, with 4 of 8 case patients infected by direct transmission of resistant virus. Zanamivir should be considered as first-line therapy for influenza in patients with lymphopenic hematological conditions and uptake of influenza vaccination encouraged to further reduce the number of susceptible individuals.
Bibliographical noteFunding Information:
M.G. has received funding from the Wellcome Trust for a Project ‘‘Development of an influenza virus sequencing pipeline’’ (October 2006 to November 2009). A.L. has received funding from Roche given for an influenza virus shedding study in oseltamivir-treated patients in collaboration with Leicester Royal Infirmary.