title: Adamantane- and oseltamivir-resistant seasonal A (H1N1) and pandemic A (H1N1) 2009 influenza viruses in Guangdong, China, during 2008 and 2009.
abstract: Adamantane and oseltamivir resistance among influenza viruses is a major concern to public health officials. To determine the prevalence of antiviral-resistant influenza viruses in Guangdong, China, 244 seasonal A (H1N1) and 222 pandemic A (H1N1) 2009 viruses were screened for oseltamivir resistance by a fluorescence-based neuraminidase (NA) inhibition assay along with NA gene sequencing. Also, 147 seasonal A (H1N1) viruses were sequenced to detect adamantane resistance markers in M2. Adamantane-resistant seasonal A (H1N1) viruses clustering to clade 2C were dominant in 2008, followed by oseltamivir-resistant seasonal A (H1N1) viruses, clustering to clade 2B during January and May 2009. In June 2009, a lineage of double-resistant seasonal A (H1N1) viruses emerged, until it was replaced by the pandemic A (H1N1) 2009 viruses. The lineage most likely resulted from reassortment under the pressure of the overuse of adamantanes. As all viruses were resistant to at least one of the two types of antiviral agents, the need for close monitoring of the prevalence of antiviral resistance is stressed.
authors: Guangdong Center for Disease Control and Prevention, Guangzhou, Guangdong, People’s Republic of China.
authors: Jie
authors: J
authors: Zhou
authors: Lirong
authors: L
authors: Zou
authors: Xin
authors: X
authors: Zhang
authors: Jiazheng
authors: J
authors: Liao
authors: Hanzhong
authors: H
authors: Ni
authors: Nianmei
authors: N
authors: Hou
authors: Yajing
authors: Y
authors: Wang
authors: Hui
authors: H
authors: Li
authors: Jie
authors: J
authors: Wu
authors: Marcel
authors: M
authors: Jonges
authors: Adam
authors: A
authors: Meijer
authors: Marion
authors: M
authors: Koopmans
authors: Changwen
authors: C
authors: Ke
references: J Virol. 2008 Jan;82(2):596-601
references: 17942553
references: Antimicrob Agents Chemother. 2006 Jul;50(7):2395-402
references: 16801417
references: Emerg Infect Dis. 2010 Jan;16(1):155-6
references: 20031069
references: J Clin Virol. 2010 Jan;47(1):23-8
references: 19962344
references: JAMA. 2006 Feb 22;295(8):891-4
references: 16456087
references: Virology. 2009 Jun 5;388(2):270-8
references: 19394063
references: Antiviral Res. 2010 Jul;87(1):16-21
references: 20385168
references: Emerg Infect Dis. 2009 Jun;15(6):966-8
references: 19523305
references: Lancet. 2005 Oct 1;366(9492):1175-81
references: 16198766
references: Antimicrob Agents Chemother. 2008 Sep;52(9):3284-92
references: 18625765
references: J Infect Dis. 2011 Jan 1;203(1):13-7
references: 21148491
references: J Infect Dis. 2007 Jul 15;196(2):249-57
references: 17570112
references: Mol Biol Evol. 2007 Aug;24(8):1596-9
references: 17488738
references: Antiviral Res. 2009 Apr;82(1):34-41
references: 19428593
references: J Infect Dis. 2001 Feb 15;183(4):523-31
references: 11170976
references: Euro Surveill. 2009 Feb 05;14(5):
references: 19215715
references: Science. 2008 Apr 18;320(5874):340-6
references: 18420927
references: Anal Biochem. 1979 Apr 15;94(2):287-96
references: 464297
references: Emerg Infect Dis. 2009 Dec;15(12):1970-2
references: 19961677
references: J Clin Virol. 2009 Nov;46(3):298-9
references: 19736041
references: Emerg Infect Dis. 2009 Apr;15(4):552-60
references: 19331731
references: Euro Surveill. 2008 Jan 31;13(5):
references: 18445375
references: Emerg Infect Dis. 2010 Jun;16(6):926-35
references: 20507742
references: Vaccine. 1999 Jul 30;17 Suppl 1:S3-10
references: 10471173
references: J Clin Microbiol. 2010 Apr;48(4):1085-92
references: 20129961
references: N Engl J Med. 2009 Mar 5;360(10):953-6
references: 19258250