Bird flu is caused by one of many Influenza (flu) viruses that can infect birds. The Influenza virus generally differ in three species (Influenza A, Influenza B and Inflenza C), according to the antigenicity of the nucleoprotein (the protein directly protects the nucleic acid). Of these, only the species Influenza A affects birds. Influenza A viruses are distinguished by their hemagglutinins (up to 16 subtypes) and neuraminidase (up to 9 subtypes), with possible recombinations between a hemagglutinin neuraminidase other, so can become many different subtypes. Generation of different subtypes is possible, quite easily, because the genome of these viruses is segmented into 8 fragments, so that upon entering a cell two different subtypes, can recombine interchanged coding segments of hemagglutinin and neuraminidase and generated a subtype.
Sometimes becomes synonymous "bird flu" virus "highly pathogenic" but it is not. A bird flu virus is any subtype of Influenza A virus that affects birds. However, a virus "highly pathogenic" is an Influenza A virus that affects birds but can provoke generalized infections with respiratory involvement not only, but also other organs. This is due to its hemagglutinin, which is the spicule viral surface with which the virus makes contact with cell receptors must be activated. The activation of Influenza virus is by standard an enzyme produced by the clear cells of the mucosa of the respiratory tract, but not by enzymes found in other locations. However, the hemagglutinins of Influenza viruses "highly pathogenic", can be activated by serine proteases enzymes produced by many cells of other organs, therefore the virus causes an infection organic mass.
The first virus that concerned in this regard was the Influenza A H5N1 virus (1997, Hong Kong, PRC), which not only caused high mortality in birds, but also did in people infected with this virus.
Since then, there have been reported occasionally other viruses Influenza A, which also cause infection in birds have caused human infections, such as: H6N1, H7N1, H7N2, H9N2, H10N7, and two subtypes, whose infection is associated with high mortality in persons: H7N9 (March, 2013) and H7N7, H5N1 addition to the previously cited.
Tests in IVAMI:
- Molecular detection of each of the species of Influenza (A, B or C) virus, and any subtypes by genomic amplification by RT-PCR of the corresponding genes, and the typing by nucleic acid sequencing.
- Subtype specific antibody detection by hemagglutination inhibition tests.
- Virus isolation in cell cultures.
- Isolation by inoculation into chicken embryo.
Type of samples required
Preservation and shipment of sample:
- Refrigerated (preferred) for less than 2 days.
- Frozen: over 2 days.
Delivery time results
Cost of RT-PCR test: