Assessment of the Susceptibility of Laboratory Animals to Cowpox Virus for the Selection of an Experimental Model

Cowpox virus, belonging to the genus Orthopoxvirus, is widely used as a model for studying orthopoxvirus infections. Despite the availability of data on the susceptibility of different animal species, its assessment under standardized experimental conditions remains limited.

The aim of this study was to assess the susceptibility of laboratory animals to cowpox virus and to substantiate the selection of an optimal experimental model.

The epizootic strain “COWPOX-CAM” of cowpox virus was used in this study. White mice, guinea pigs, and rabbits were employed as experimental models and infected via the intradermal route. Clinical observations were performed, and the course of the infectious process and the development of pathological changes were evaluated.

In guinea pigs, the infection was mild and not associated with mortality. In white mice, the clinical manifestations of infection were mild and were not accompanied by the development of characteristic skin lesions. In rabbits, a pronounced clinical course was observed, including both local and systemic manifestations of infection.

The results obtained indicate that rabbits demonstrate the highest susceptibility to cowpox virus and can be considered the most appropriate experimental model for studying the pathogenesis of infection and evaluating the efficacy of vaccines and therapeutic agents.

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