Avian influenza is currently considered one of the major epidemiological and biological threats to global public health. Highly pathogenic strains such as H5N1 and H7N9 are of particular concern due to their zoonotic nature, high mortality rate, and pandemic potential. This article analyzes the virological characteristics, immunopathogenesis, and modern laboratory diagnostic methods of H5N1 and H7N9 viruses. The role of the segmented RNA genome of Influenza A virus, as well as hemagglutinin (HA) and neuraminidase (NA) proteins in viral virulence, is discussed. In addition, the mechanisms of innate and adaptive immune responses, cytokine storm development, and lung tissue damage are scientifically described. The diagnostic significance of RT-PCR, ELISA, serological, and virological methods is also reviewed. The findings indicate that early detection of H5N1 and H7N9 viruses, detailed investigation of immunopathological processes, and development of effective preventive measures remain among the priority areas of modern medicine.

Parranda grippi, H5N1, H7N9, Avian influenza, Influenza A virusi, immunopatogenez, zoonoz infeksiya, RT-PCR, ELISA, gemagglutinin, neyraminidaza, sitokin bo‘roni, virusologik diagnostika, immun javob, pandemik potensial.

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