Objectives: To perform genetic analysis of influenza A and B viruses in Myanmar from 2005 to 2007 and to determine the prevalence of amantadine-resistant influenza A viruses. Methods: Phylogenies of the HA and NA genes were analyzed and mutations in M2 that confer resistance to amantadine were screened. Results: Influenza in Myanmar exhibited seasonality, which coincided during the rainy season from June to August. Out of 2,618 samples, 76 influenza A and 132 influenza B viruses were isolated. Phylogenetic analysis showed that in 2005, 11 A/H1N1 isolates formed one cluster with A/Solomon Islands/3/2006 and were amantadine-sensitive strains. One A/H3N2 isolate was amantadine-resistant harboring S31N mutation in M2 and possessing S193F and D225N substitutions in HA (clade N), similar to A/Wisconsin/67/2005. No viruses were isolated in 2006 due to sample storage failure. In 2007, all 64 A/H3N2 isolates were amantadine-resistant and similar to A/Brisbane/10/2007. For influenza B, 3 Yamagata-lineage and 17 Victoria-lineage isolates were detected in 2005 and 112 Victoria-lineage viruses were isolated in 2007. All Victoria-lineage isolates were reassortants possessing NA derived from the Yamagata lineage. Conclusion: Continuous surveillance in tropical countries is important for elucidating the seasonality of influenza and determining the molecular characteristics of circulating strains.
© 2009 S. Karger AG, Basel
- Amantadine-resistant influenza A viruses
- Human influenza A and B viruses, epidemiology
- Influenza A/H1N1 viruses
- Influenza A/H3N2 Isolates
- Influenza B viruses
- Influenza surveillance, Myanmar
- Sentinel influenza surveillance sites
- Victoria-lineage isolates
- Yamagata-lineage isolates
- Escuret V, Frobert E, Bouscambert-Duchamp M, et al: Detection of human influenza A (H1N1) and B strains with reduced sensitivity to neuraminidase inhibitors. J Clin Virol 2008;41:25–28.
- Suzuki H, Saito R, Masuda H, et al: Emergence of amantadine-resistant influenza A viruses: epidemiological study. J Infect Chemother 2003;9:195–200.
- Gachara G, Ngeranwa J, Magana JM, et al: Influenza virus strains in Nairobi, Kenya. J Clin Virol 2006;35:117–118.
- Hasegawa G, Kyaw Y, New HM, et al: Epidemiological study of influenza virus infections in Yangon, Myanmar. Trop Med Health 2006;34:3–6.
- Viboud C, Alonso WJ, Simonsen L: Influenza in tropical regions. PLoS Med 2006;3:468–471.
- Russell CA, Jones TC, Barr IG, et al: The global circulation of seasonal influenza A (H3N2) viruses. Science 2008;320:340–346.
- Li D, Saito R, Le MTQ, et al: Genetic analysis of influenza A/H3N2 and A/H1N1 viruses circulating in Vietnam from 2001 to 2006. J Clin Microbiol 2008;46:399–405.
- Bright RA, Medina MJ, Xu X, et al: Incidence of adamantane resistance among influenza A (H3N2) viruses isolated worldwide from 1994 to 2005: a cause for concern. Lancet 2005;366:1175–1181.
- Barr IG, Hurt AC, Iannello P, et al: Increased amantadine resistance in influenza A (H3) viruses in Australia and neighboring countries in 2005. Antiviral Res 2007;73:112–117.
- Saito R, Li D, Suzuki H: Amantadine-resistant influenza A (H3N2) virus in Japan, 2005–2006. N Engl J Med 2007;356:312–313.
- Bright RA, Shay DK, Shu B, et al: Adamantane resistance among influenza A viruses isolated early during the 2005–2006 influenza season in the United States. JAMA 2006;295:891–894.
- Hasegawa G, Kyaw Y, Li D, et al: Influenza virus infections in Yangon, Myanmar. J Clin Virol 2006;37:233–234.
- Center for Disease Control: Concepts and Procedures for Laboratory-Based Influenza Surveillance. Atlanta, US Department of Health, Public Health Service, 1982.
- Hoffmann E, Stech J, Guan Y, et al: Universal primer set for the full-length amplification of all influenza A viruses. Arch Virol 2001;146:2275–2289.
- Burland TG: DNASTAR’s Lasergene sequence analysis software. Methods Mol Biol 2000;132:71–91.
- Tamura K, Dudley J, Nei M, et al: MEGA4: Molecular Evolutionary Genetics Analysis (MEGA) software version 4.0. Mol Biol Evol 2007;24:1596–1599.
- Hay AJ, Wolstenholme AJ, Skehel JJ, et al: The molecular basis of the specific anti-influenza action of amantadine. EMBO J 1985;4:3021–3024.
- Schnell JR, Chou JJ: Structure and mechanism of the M2 proton channel of influenza A virus. Nature 2008;451:591–595.
- WHO: Recommended composition of influenza virus vaccines for use in the 2005–2006 influenza season. Wkly Epidemiol Rec 2005;80:65–76.
- WHO: Recommended composition of influenza virus vaccines for use in the 2007–2008 influenza season. Wkly Epidemiol Rec 2007;82:69–74.
- Rambaut A, Pybus OG, Nelson MI, et al: The genomic and epidemiological dynamics of human influenza A virus. Nature 2008;453:615–619.
- Shek LP, Lee BW: Epidemiology and seasonality of respiratory tract virus infections in the tropics. Paediatr Respir Rev 2003;4:105–111.
- Simmerman JM, Thawatsuoha P, Kingnate D, et al: Influenza in Thailand: a case study for middle income countries. Vaccine 2004;23:182–187.
- Nguyen HLK, Saito R, Ngiem HK, et al: Epidemiology of influenza in Hanoi, Vietnam, 2001–2003. J Infect 2007;55:58–63.
- Tsai HP, Kuo PH, Liu CC, et al: Respiratory viral infections among pediatric inpatients and outpatients in Taiwan from 1997 to 1999. J Clin Microbiol 2001;39:111–118.
- WHO: Summary of influenza activity, September 2004–August 2005. Wkly Epidemiol Rec 2005;80:353–360.
- WHO: Influenza in the world, September 2006–August 2007. Wkly Epidemiol Rec 2007;82:357–360.
- Saito R, Suzuki Y, Li D, et al: Increased incidence of adamantine-resistant influenza A(H1N1) and A(H3N2) viruses during the 2006–2007 influenza season in Japan. J Infect Dis 2008;197:630–632.
- Zaraket H, Dbaibo G, Salam O, et al: Influenza virus infections in Lebanese children in the 2007–2008 season. Jpn J Infect Dis 2009;62:137–138.
- Reyes F, Aziz S, Winchester B, et al: Influenza in Canada: 2007–2008 season update. Can Commun Dis Rep 2008;34:1–9.
- CDC: Influenza activity – United States and worldwide, 2007–2008 season. MMWR 2008;57:692–697.
- Barr IG, Deng YM, Iannello P, et al: Adamantane resistance in influenza A(H1) viruses increased in 2007 in South East Asia but decreased in Australia and some other countries. Antiviral Res 2008;80:200–205.
- WHO: Recommended composition of influenza virus vaccines for use in the 2008–2009 influenza season. Wkly Epidemiol Rec 2008;83:77–88.
- Saito R, Li D, Suzuki Y, et al: High prevalence of amantadine-resistance influenza A (H3N2) in six prefectures, Japan, in the 2005–2006 season. J Med Virol 2007;79:1569–1576.
- Hay AJ, Gregory V, Douglas AR, et al: The evolution of human influenza viruses. Phil Trans R Soc Lond B 2001;356:1861–1870.
- Berton MT, Naeve CW, Webster RG: Antigenic structure of the influenza B virus hemagglutinin: nucleotide sequence analysis of antigenic variants selected with monoclonal antibodies. J Virol 1984;52:919–927.
- Lin YP, Gregory V, Bennett H, et al: Genetic reassortment among recently circulating human influenza A and B viruses. Int Congr Ser 2004;1263:178–183.
- Shaw MW, Xu X, Li Y, et al: Reappearance and global spread of variants of influenza B/Victoria/2/87 lineage viruses in the 2000–2001 and 2001–2002 seasons. Virology 2002;303:1–8.
- Jian JW, Lai CT, Kuo CY, et al: Genetic analysis and evaluation of the reassortment of influenza B viruses isolated in Taiwan during the 2004–2006 and 2006–2007 epidemics. Virus Res 2008;131:243–249.
- Lin JH, Chiu SC, Shaw MW, et al: Characterization of the epidemic influenza B viruses isolated during 2004–2005 season in Taiwan. Virus Res 2007;124:204–211.
- Chen R, Holmes EC: The evolutionary dynamics of human influenza B virus. J Mol Evol 2008;66:655–663.
- Besselar TG, Botha L, McAnerney JM, et al: Antigenic and molecular analysis of influenza A (H3N2) virus strains isolated from a localized influenza outbreak in South Africa in 2003. J Med Virol 2004;73:71–78.
- Nakagawa N, Kubota R, Maeda A, et al: Heterogeneity of influenza B virus strains in one epidemic season differentiated by monoclonal antibodies and nucleotide sequences. J Clin Microbiol 2000;38:3467–3469.
Department of Public Health
Graduate School of Medical and Dental Sciences, Niigata University
1-757 Asahimachi-dori, Niigata 951-8510 (Japan)
Tel. +81 25 227 2129, Fax +81 25 227 0765, E-Mail email@example.com
Received: May 25, 2009
Accepted after revision: July 20, 2009
Published online: September 17, 2009
Number of Print Pages : 11
Number of Figures : 4, Number of Tables : 3, Number of References : 43
Intervirology (International Journal of Basic and Medical Virology)
Vol. 52, No. 6, Year 2009 (Cover Date: November 2009)
Journal Editor: Liebert U.G. (Leipzig)
ISSN: 0300-5526 (Print), eISSN: 1423-0100 (Online)
For additional information: http://www.karger.com/INT
Copyright / Drug Dosage / Disclaimer
Copyright: All rights reserved. No part of this publication may be translated into other languages, reproduced or utilized in any form or by any means, electronic or mechanical, including photocopying, recording, microcopying, or by any information storage and retrieval system, without permission in writing from the publisher or, in the case of photocopying, direct payment of a specified fee to the Copyright Clearance Center.
Drug Dosage: The authors and the publisher have exerted every effort to ensure that drug selection and dosage set forth in this text are in accord with current recommendations and practice at the time of publication. However, in view of ongoing research, changes in goverment regulations, and the constant flow of information relating to drug therapy and drug reactions, the reader is urged to check the package insert for each drug for any changes in indications and dosage and for added warnings and precautions. This is particularly important when the recommended agent is a new and/or infrequently employed drug.
Disclaimer: The statements, opinions and data contained in this publication are solely those of the individual authors and contributors and not of the publishers and the editor(s). The appearance of advertisements or/and product references in the publication is not a warranty, endorsement, or approval of the products or services advertised or of their effectiveness, quality or safety. The publisher and the editor(s) disclaim responsibility for any injury to persons or property resulting from any ideas, methods, instructions or products referred to in the content or advertisements.