Genetic characterization of influenza virus circulating in Brazilian pigs during 2009 and 2010 reveals a high prevalence of the pandemic H1N1 subtype

Influenza and Other Respiratory Viruses

Daniela S. Rajão²  Adrienny T. R. Costa⁴  Bruno S. A. F. Brasil⁵  Helen L. Del Puerto³  Fernanda G. Oliveira²  Fabiana Alves²  Gissandra F. Braz²  Jenner K. P. Reis²  Roberto M. C. Guedes¹  Zélia I. P. Lobato² 

[1] Departamento de Clínica e Cirurgia Veterinárias, Escola de Veterinária, Universidade Federal de Minas Gerais, Belo Horizonte, Brazil;Departamento de Medicina Veterinária Preventiva, Escola de Veterinária, Universidade Federal de Minas Gerais, Belo Horizonte, Brazil;Departamento de Patologia Geral, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Belo Horizonte, Brazil;Instituto de Pesquisas Veterinárias Especializadas, IPEVE, Belo Horizonte, Brazil;Laboratório de Genética, Departamento de Zootecnia, Escola de Veterinária, Universidade Federal de Minas Gerais, Belo Horizonte, Brazil

关键词: Genetic characterization;    hemagglutinin;    influenza A virus;    pandemic;    swine;   

DOI  :  10.1111/irv.12072

来源: Wiley

【 摘 要 】

Abstract

Background

Influenza A viruses circulating in pigs in Brazil are still not characterized, and only limited data are available about swine influenza epidemiology in the country. Therefore, we characterized the hemagglutinin (HA) and neuraminidase (NA) genes of influenza viruses isolated from Brazilian pigs. We also evaluated one case of probable swine-to-human transmission.

Methods

Twenty influenza viruses isolated from pigs during 2009–2010 in five Brazilian states (Minas Gerais, Sao Paulo, Parana, Rio Grande do Sul, and Mato Grosso) were used. One human isolate, from a technician who became ill after visiting a swineherd going through a respiratory disease outbreak, was also used in the study. Phylogenetic analysis for the HA and NA genes and hemagglutinin amino acid sequence alignment were performed.

Results

All isolates clustered with pandemic H1N1 2009 (pH1N1) viruses and appeared to have a common ancestor. Genetic diversity was higher in the HA than in the NA gene, and the amino acid substitution S203T in one of HA's antigenic sites was found in most of the samples. The human isolate was more related to swine isolates from the same herd visited by the technician than to other human isolates, suggesting swine-to-human transmission.

Conclusion

Our results show that pH1N1 was disseminated and the predominant subtype in Brazilian pigs in 2009–2010.

【 授权许可】

Unknown   
© 2012 John Wiley & Sons Ltd