Spread of highly pathogenic avian influenza in Kazakhstan: investigating the role of bird migration and threats to poultry farming

Abstract

Background and Aim. Highly pathogenic avian influenza (HPAI) remains a serious threat to industrial poultry farming and human health. The virus is highly variable and can be transmitted through the migratory flows of wild birds, which contribute to its widespread distribution. This study aimed to analyze the epidemiology of HPAI in Kazakhstan and assess the role of migratory birds therein.

Materials and Methods. The study assessed data on outbreaks of HPAI in Kazakhstan for the period 2005 to 2024. Information on migratory bird species in Kazakhstan territories and their migration routes was obtained by the “Institute of Zoology”. The research applied classical methods of epidemiological analysis, statistical modeling of epizootics, and data visualization using ArcGIS Pro software. Results. Over the past 20 years (2005 to 2024), outbreaks of HPAI have been periodically recorded in Kazakhstan, with cases of infection in both domestic and wild birds. The pathogens mainly comprised viruses of the H5N1, H5N8, and other H5 strains. Wild migratory birds played the main role in the emergence and spread of HPAI. The territory of Kazakhstan contained the convergence point of two of their most important migration routes: the Central Asian-Indian and West Asian-African routes. A total of 489 bird species has been registered in Kazakhstan, most of which are seasonal migrants flying through the country; accordingly, they have a significant impact on the epizootic process of HPAI.

Conclusion. Analysis of epizootiological data showed that the dates and locations of HPAI outbreaks directly correlated with the stages and routes of the seasonal migration of migratory birds. Predictive modeling of virus spread showed that the northern and western regions of the country, where most of the country’s poultry farms are located, were at the highest risk.