Introduction. This article presents the results of isolation of camel smallpox virus (Poxviridae: Orthopoxvirus: Camelpox virus, CMLPV) and study of its reproductive properties on sensitive biological systems.Material and methods. The epizootic strain M-96 of the virus as well as its attenuated variants KM-40 and KM-70 obtained by sequential passivation were used in the study. Isolation of the pathogen from suspension of biopsy specimens was performed on cell culture and in embryonated chicken eggs (ECEs). All experiments were performed with the number of replications ensuring obtaining reliable results.Results. The CMLPV was isolated from the crusts and pox papules of the skin taken from sick camels (Camelus bactrianus) during an outbreak in various districts of the Mangistau region at the end of 2019. The signs of pathogen reproduction on chorio-allantoic membrane (CAM) were observed from 3 passages. The obtained virus caused formation of pathological changes on the CAM in the form of elevated dot or solid white formations separated from the surrounding tissue, with hemorrhagic foci in the center. The reproductive properties of the isolate on sensitive biological systems were determined in comparison with the epizootic CMLPV strain M-96, isolated earlier in the territory of Kazakhstan during the outbreak 23–24 years ago, as well as its attenuated variants. The isolated virus was given the conventional name M-2020.Discussion. When studied in two sensitive cultivation systems (cell culture and ECEs), strain M-96 and its attenuated variants KM-40, KM-70, which were used in the experiments as a control, demonstrated high infectious activity with titer 4.75-6.75 lg TCID50/cm3, while for the examined isolate M-2020 of CMLPV had the significantly lower values (3.00-4.75 lg TCID50/cm3, p 0,05).

This study continues earlier work aimed at identifying potential natural reservoirs of camelpox virus (CMLV) during interepizootic periods. In 2023–2024, field expeditions in western Kazakhstan led to the collection and analysis of biological samples from camels, rodents and hematophagous insects. Despite the absence of clinical symptoms, PCR-positive results were obtained from camel blood samples. These samples underwent molecular genetic analysis, including viral DNA detection and whole-genome sequencing. Using next-generation sequencing, the complete genome of the Camelpox virus/Beineu/2023 isolate (202.273 bp) was obtained and deposited in the NCBI database (accession number PV920573.1). The isolate showed >98% genetic similarity to the previously described Kazakhstan strain M-96, indicating long-term local circulation of a genetically stable variant. Phylogenetic analysis confirmed the isolate’s evolutionary conservatism and close relationship with other CMLV strains. The findings suggest that camels serve as a natural reservoir, enabling viral persistence and potential reactivation under stress-related conditions. The observed geographic clustering underscores the need for region-specific molecular surveillance to ensure timely detection of new variants and prevent cross-border spread.

The paper presents the results of determining the optimal immunising dose of inactivated vaccine against camelpox from the strain "KM - 40", obtained from the Republican Depository of especially dangerous pathogens of the Research Institute of Biological Safety Problems. The results of studies showed that intramuscular administration of inactivated vaccine against camelpox on camel rats formed antibodies to camelpox virus, the titre of which depended on the dose of the preparation. At 14 days after vaccination no antibodies were detected in the blood serum of camels immunised with the vaccine in the volumes of 2.0 and 3.0 ml, whereas in animals immunised in the volume of 5.0 ml the antibody titre was 1:2 and 1:4 in the neutralisation reaction and diffusion precipitation reaction, respectively. For use in the field, we recommend the use of 5.0 ml vaccine. If all the requirements specified in the regulations on vaccine production and control are met, this dose of the vaccine preparation ensures the formation of intense immunity against camelpox.

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.

This study continues earlier work aimed at identifying potential natural reservoirs of camelpox virus (CMLV) during interepizootic periods. In 2023-2024, field expeditions in western Kazakhstan led to the collection and analysis of biological samples from camels, rodents and hematophagous insects. Despite the absence of clinical symptoms, PCR-positive results were obtained from camel blood samples. These samples underwent molecular genetic analysis, including viral DNA detection and whole-genome sequenc-ing. Using next-generation sequencing, the complete genome of the Camelpox vi-rus/Beineu/2023 isolate (202.273 bp) was obtained and deposited in the NCBI database (accession number PV920573.1). The isolate showed >98% genetic similarity to the previ-ously described Kazakhstan strain M-96, indicating long-term local circulation of a genet-ically stable variant. Phylogenetic analysis confirmed the isolate’s evolutionary conserva-tism and close relationship with other CMLV strains. The findings suggest that camels serve as a natural reservoir, enabling viral persistence and potential reactivation under stress-related conditions. The observed geographic clustering underscores the need for re-gion-specific molecular surveillance to ensure timely detection of new variants and pre-vent cross-border spread.

Cowpox is a disease characterized by rapid development and a number of characteristic symptoms. The disease is characterized by a significant increase in body temperature, causing general weakness and loss of appetite. This in turn affects milk production. Papules appear on the cow's udder, which over time turn into abscesses and cracks. Due to discomfort and pain, the cow develops a wide stance. The CPXV genome has the most complete gene set of any orthopoxvirus. This unique feature of CPXV makes it ideal for mutating into different strains of the virus. This is a double-stranded DNA virus. The virus has an envelope that surrounds the virion. Literature studies that provide useful information on the clinical manifestations of sensitivity to this virus for various animal species and humans are analyzed. Studying the life cycle of this virus is also an important aspect, since uncovering its mechanisms allows for the development of effective control and control strategies. Specific examples of clinical manifestations associated with sensitivity to this virus in different animal species and humans are given. This allows for a more complete assessment of its potential consequences and impact on public health