[Development of polymerase chain reaction-based test systems for influenza A virus isolation and typing]

Influenza viruses are spread worldwide and cause the disease in birds and mammals, including human beings. Moreover, birds are the natural reservoir of influenza A viruses. Early detection of newly emerging influenza viruses requires permanent monitoring. Traditional viral shedding methods using cell cultures and chicken embryos are time-consuming and laborious analysis when a large number of samples are examined. The paper describes the use of polymerase chain reaction-based test systems to detect influenza A virus and to differentiate its two subtypes: H5 and H7. The developed test systems were evaluated on 19 reference influenza A virus strains. Thereafter, more than 1500 samples from wild and domestic birds, collected in the Russian Federation in 2004-2006, were studied. The data of these test systems were compared with the techniques of viral shedding in the cell cultures and chicken embryos.