Abstract
Our understanding of the ecology and evolution of avian influenza (AIV) viruses in wild birds is primarily derived from studies in the Northern Hemisphere, particularly among waterfowl. However, significant gaps exist in our knowledge regarding Siberia, a vast region stretching from the Ural Mountains to the Kamchatka Peninsula. Notably, much of this territory remains uninhabited by migratory waterfowl during winter, when they migrate predominantly to Asian countries, and interact with substantial reservoirs of the virus in domestic birds. Utilizing over 500 complete genomes collected during a decade of monitoring, we analyzed the genetic patterns of AIVs across Siberia's breeding territories. Our findings reveal distinct geographical patterns and specific clades for both low-pathogenic and high-pathogenic H5Nx viruses. We traced the evolution of H5 viruses in Siberia, noting clade replacements—2.2, 2.3.2, 2.3.2.1C, and 2.3.4.4—that have led to outbreaks among wild and domestic birds in Russia, as well as marine mammals. A notable outbreak in seals occurred in the Sea of Okhotsk in 2023, highlighting concerns about interspecific transmission. For low-pathogenic strains, we identified genetically distinct groups specific to various Siberian regions. In the Far East, we observed concurrent circulation of classic Eurasian H6Nx viruses alongside Chinese endemic H6N6 viruses from domestic birds, with evidence of reassortment between these strains directly illustrating the interaction between wild and domestic reservoirs.
Our study underscores the necessity for ongoing surveillance to detect emerging variants of AIV and to facilitate prevention of outbreaks.
This work was supported by Russian Science Foundation (grant # 23-44-00026).
Our study underscores the necessity for ongoing surveillance to detect emerging variants of AIV and to facilitate prevention of outbreaks.
This work was supported by Russian Science Foundation (grant # 23-44-00026).
Co-Author(s)
Kirill Sharshov, Ivan Sobolev, Nikita Dubovitskiy, Anastasiya Derko, Arina Loginova, Tatiana Murashkina, Nikita Kasianov, Olga Kurskaya, Aleksandr Alekseev, Alexander Shestopalov
1 - Laboratory of molecular epidemiology and biodiversity of viruses, Institute of Virology, Federal Research Center of Fundamental and Translational Medicine, Novosibirsk, Russia; sharshov@yandex.ru
Abstract Category
Notable outbreaks, field and molecular epidemiology, and surveillance in wild birds