Rare influenza A (H3N2) variants with reduced sensitivity to antiviral drugs

DOI: 10.3201/eid1603.091321
Suggested citation for this article: Dapat C, Suzuki Y, Saito R, Kyaw Y, Myint YY, Lin N, et al. Rare influenza A (H3N2) variants with reduced sensitivity to antiviral drugs. Emerg Infect Dis. 2010 Mar; [Epub ahead of print]

Rare Influenza A (H3N2) Variants with Reduced Sensitivity to Antiviral Drugs
Clyde Dapat,1 Yasushi Suzuki,1 Reiko Saito, Yadanar Kyaw, Yi Yi Myint, Nay Lin, Htun Naing Oo, Khin Yi Oo, Ne Win, Makoto Naito, Go Hasegawa, Isolde C. Dapat, Hassan Zaraket, Tatiana Baranovich, Makoto Nishikawa, Takehiko Saito, and Hiroshi Suzuki
Author affiliations: Niigata University, Niigata, Japan (C. Dapat, Y. Suzuki, R. Saito, M. Naito, G. Hasegawa, I.C. Dapat, H. Zaraket, T. Baranovich, H. Suzuki); National Institute of Animal Health, Tsukuba City, Japan (T. Saito); Niigata Prefectural Institute of Public Health and Environmental Sciences, Niigata (M. Nishikawa); Sanpya Hospital, Yangon, Myanmar (Y. Kyaw); National Health Laboratory, Yangon (K.Y. Oo, N. Win); and Central Myanmar Department of Medical Research, Nay Pyi Taw, Myanmar (Y.Y. Myint, N. Lin, H.N. Oo)

1These authors contributed equally to this article.
In 2007 and 2008 in Myanmar, we detected influenza viruses A (H3N2) that exhibited reduced sensitivity to both zanamivir and amantadine. These rare and naturally occurring viruses harbored a novel Q136K mutation in neuraminidase and S31N mutation in M2.

Adamantanes and neuraminidase inhibitors (NAI) are the 2 classes of drugs indicated for preventing or treating influenza virus infection. In 2005, the high prevalence of influenza viruses A (H3N2) with S31N mutation in M2 limited the effectiveness of amantadine (1,2). In 2008, the emergence of subtype H1N1 with H274Y mutation in neuraminidase (NA) raised concerns about the use of oseltamivir (3,4). On the other hand, the incidence of zanamivir-resistant viruses was low (5). In 1998, 1 case of zanamivir-resistant influenza B virus, which was isolated from an immunocompromised child who underwent prolonged zanamivir treatment, was reported (6). In 2008, subtype H3N2 with D151A/V mutations in NA demonstrated reduced zanamivir sensitivity...

abrir aquí para acceder al documento CDC EID completo, pdf de 8 páginas:
http://www.cdc.gov/eid/content/16/3/pdfs/09-1321.pdf