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Cite: Panteleienko O., Tarasov O., Shevchenko M., Savchenyuk M., Goncharenko V., Mazur T. Virusleikozukotiv: etiolohichni, patohenetychnitaepidemiolohichniaspektyinfektsiivyevropi (ohliadovastattia). [Feline leukemia virus: etiologic, pathogenetic and epidemiologic aspects of infection in Europe (review article)]. Veterynarna biotekhnolohiia – Veterinary biotechnology, 46, 97-123. https://doi.org/10.31073/vet_biotech46-07 [in Ukrainian].

 

Panteleienko O. 1, e-mail: This email address is being protected from spambots. You need JavaScript enabled to view it.,

Tarasov O. 2, e-mail: This email address is being protected from spambots. You need JavaScript enabled to view it.,

ShevchenkoM. 1, e-mail: This email address is being protected from spambots. You need JavaScript enabled to view it.

SavchenyukM. 1, e-mail: This email address is being protected from spambots. You need JavaScript enabled to view it.

GoncharenkoV. 1, e-mail: This email address is being protected from spambots. You need JavaScript enabled to view it.

Mazur T. 1, e-mail: This email address is being protected from spambots. You need JavaScript enabled to view it.

1 Bila Tserkva National Agrarian University

2 Institute of Veterinary Medicine, NAAS of Ukraine, Kyiv, Ukraine 

 

FELINE LEUKEMIA VIRUS: ETIOLOGIC, PATHOGENETIC AND EPIDEMIOLOGIC ASPECTS OF INFECTION IN EUROPE (REVIEW ARTICLE)

Introduction. Feline leukemia virus (FeLV) is one of the most significant viral threats to domestic cats, responsible for progressive immunosuppression, oncogenesis, and increased susceptibility to secondary infections. Despite six decades of research, FeLV remains a challenge due to its genetic variability, complex pathogenesis, and diagnostic difficulties. The infection presents in progressive, regressive, focal, and abortive forms, complicating clinical identification and requiring multi-faceted diagnostic approaches.

The goal of the work. This review aims to comprehensively analyze the current knowledge about FeLV, including its etiology, molecular structure, replication, clinical manifestations, diagnostic strategies, and prevalence across Europe. Special attention is given to the variability in epidemiological data and the identification of research gaps hindering effective disease monitoring and prevention.

Materials and methods. The study follows the PRISMA guidelines for systematic reviews. Peer-reviewed publications from 2010–2024 were retrieved from PubMed, Scopus, Web of Science, and Google Scholar using keywords such as “FeLV,” “pathogenesis,” “epidemiology,” and “Europe.” Only full-text articles with clear methodological descriptions and original data were included.

Results of research and discussion. The virus exists in endogenous and exogenous forms, with subgroups FeLV-A, -B, and -C being clinically relevant. Progressive infection is associated with persistent viremia and poor prognosis, while regressive and abortive forms may remain latent or subclinical. Diagnostic accuracy varies: POC tests for antigen p27 are widely used but limited in detecting regressive cases, while PCR remains the gold standard for proviral DNA detection. Epidemiological data reveal striking regional differences in FeLV prevalence, ranging from <1% in Northern Europe to >20% in Eastern and Southern regions. Methodological inconsistencies across studies hinder pan-European surveillance.

Conclusions and prospects for further research. FeLV control requires improved diagnostic algorithms, expanded surveillance programs, and harmonization of testing protocols across Europe. Future studies should prioritize large-scale, multicenter investigations with standardized methods to inform vaccination strategies and public health policy. Understanding host-virus interactions and the role of endogenous FeLV elements is essential for advancing prevention and therapeutic options.

Keywords: feline viral leukemia, retrovirus, pathogenesis, clinical signs, prevalence, diagnosis.

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