Impact of antigenic and genetic drift on the serologic surveillance of H5N2 avian influenza viruses

نویسندگان

  • Magdalena Escorcia
  • Karol Carrillo-Sánchez
  • Santiago March-Mifsut
  • Joaquin Chapa
  • Eduardo Lucio
  • Gerardo M Nava
چکیده

BACKGROUND Serologic surveillance of Avian Influenza (AI) viruses is carried out by the hemagglutination inhibition (HI) test using reference reagents. This method is recommended by animal health organizations as a standard test to detect antigenic differences (subtypes) between circulating influenza virus, vaccine- and/or reference- strains. However, significant discrepancies between reference antisera and field isolates have been observed during serosurveillance of influenza A viruses in pig and poultry farms. The objective of this study was to examine the effects of influenza virus genetic and antigenic drift on serologic testing using standard HI assays and reference reagents. Low pathogenic AI H5N2 viruses isolated in Mexico between 1994 and 2008 were used for phylogenetic analysis of AI hemagglutinin genes and for serologic testing using antisera produced with year-specific AI virus isolates. RESULTS Phylogenetic analysis revealed significant divergence between early LPAI H5N2 viruses (1994 - 1998) and more recent virus field isolates (2002 - 2008). Results of the HI test were markedly influenced by the selection of the AI H5N2 virus (year of isolation) used as reference antigen for the assay. These analyses indicate that LPAI H5N2 viruses in Mexico are constantly undergoing genetic drift and that serosurveillance of AI viruses is significantly influenced by the antigen or antisera used for the HI test. CONCLUSIONS Reference viral antigens and/or antisera need to be replaced constantly during surveillance of AI viruses to keep pace with the AI antigenic drift. This strategy should improve the estimation of antigenic differences between circulating AI viruses and the selection of suitable vaccine strains.

برای دانلود رایگان متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید

ثبت نام

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

منابع مشابه

Antigenic drift in H5N1 avian influenza virus in poultry is driven by mutations in major antigenic sites of the hemagglutinin molecule analogous to those for human influenza virus.

H5N1 highly pathogenic avian influenza virus has been endemic in poultry in Egypt since 2008, notwithstanding the implementation of mass vaccination and culling of infected birds. Extensive circulation of the virus has resulted in a progressive genetic evolution and an antigenic drift. In poultry, the occurrence of antigenic drift in avian influenza viruses is less well documented and the mecha...

متن کامل

Molecular Surveillance of Avian Influenza in Bird Parks of Tehran, Iran

BACKGROUND: Avian influenza (AI) viruses have been isolated from a wide diversity of free-living avian species representing several orders. Since 1998, H9N2 AI outbreaks have been one of the major problems in Iranian poultry industry. In 2006, H5N1 was reported in swans in the north of Iran first , but until now there has been no official report from commercial flocks in Iran. OBJECTIVES: The...

متن کامل

Development and Evaluation of Real-Time RT-PCR Test for Quantitative and Qualitative Recognition of Current H9N2 Subtype Avian Influenza Viruses in Iran

Avian influenza H9N2 subtype viruses have had a great impact on Iranian industrial poultry production economy since introduction in the country. To approach Rapid and precise identification of this viruses as control measures in poultry industry, a real time probe base assay was developed to directly detect a specific influenza virus of H9N2 subtype -instead of general detection of Influenza A ...

متن کامل

Effect of passive immunization on immunogenicity and protective efficacy of vaccination against a Mexican low‐pathogenic avian H5N2 influenza virus

BACKGROUND Despite the use of vaccines, low-pathogenic (LP) H5N2 influenza viruses have continued to circulate and evolve in chickens in Mexico since 1993, giving rise to multiple genetic variants. Antigenic drift is partially responsible for the failure to control H5N2 influenza by vaccination; the contribution of maternal antibodies to this problem has received less attention. METHODS We in...

متن کامل

Characterization of Highly Pathogenic Avian Influenza Virus A(H5N6), Japan, November 2016

Highly pathogenic avian influenza viruses (HPAIVs) A(H5N6) were concurrently introduced into several distant regions of Japan in November 2016. These viruses were classified into the genetic clade 2.3.4.4c and were genetically closely related to H5N6 HPAIVs recently isolated in South Korea and China. In addition, these HPAIVs showed further antigenic drift.

متن کامل

ذخیره در منابع من


  با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید

عنوان ژورنال:

دوره 6  شماره 

صفحات  -

تاریخ انتشار 2010