Assessment of the epizootic situation of canine leptospirosis in Saint Petersburg

Leptospirosis is a zoonotic disease that occurs predominantly in dogs in megacities, which makes the control and prevention of this disease particularly relevant for protecting the health of pets and the general population. Dogs become infected through contact with the urine of carriers or through contaminated environments where leptospires persist for long periods [1]. Serological monitoring was conducted to identify the dominant leptospire serogroup in dogs in St. Petersburg. It was found that in the period from 2022 to 2024, the predominant serogroup was Icterohaemorrhagiae (463 cases), which is confirmed by high antibody titers up to 1:1600. When analyzing antibodies to serogroups in association with the dominant serogroup, Cynopteri (52 samples) and Pomona (50 samples) were the most common. The lowest number of findings (3 samples each) was recorded for the serogroups Bataviae, Tarassovi, and Sejroe. The use of a dog leptospirosis vaccine provides protection against certain serogroups, namely Icterohaemorrhagiae, Canicola, and Grippotyphosa. However, there are no domestic vaccines in the Russian Federation that include the following serogroups: Cynopteri, Pomona, Pyrogenes, Autumnalis, Ballum, Hebdomadis, Javanica, Australis, Bataviae, Tarassovi, and Sejroe. Therefore, leptospirosis should be included in the differential diagnosis of vaccinated dogs showing clinical signs of an infectious disease. Another important task is to find fresh vaccine strains of leptospires, as the currently used strains are quite outdated, which may have led to a partial loss of their immunogenic properties. The obtained data require strengthening of preventive measures aimed at improving the epizootic situation of leptospirosis in dogs in St. Petersburg. The development and use of polyvalent vaccines containing antigens of the most common leptospire serogroups in the region, as well as the implementation of a regular serological monitoring system among the city's dog population, are of great importance.

1. Sykes JE, Francey T, Schuller S, Stoddard RA, Cowgill LD, Moore GE. Updated ACVIM consensus statement on leptospirosis in dogs // J Vet Intern Med. 2023 NovDec;37(6):1966-1982. doi: 10.1111/jvim.16903. Epub 2023 Oct 20. PMID: 37861061; PMCID: PMC10658540.

2. Vincent AT, Schiettekatte O, Goarant C, Neela VK, Bernet E, Thibeaux R, Ismail N, Mohd Khalid MKN, Amran F, Masuzawa T, Nakao R, Amara Korba A, Bourhy P, Veyrier FJ, Picardeau M. Revisiting the taxonomy and evolution of pathogenicity of the genus Leptospira through the prism of genomics // PLoS Negl Trop Dis. 2019 May 23;13(5):e0007270. doi: 10.1371/journal.pntd.0007270. PMID: 31120895; PMCID: PMC6532842.

3. Klaasen HL, van der Veen M, Molkenboer MJ, Sutton D. A novel tetravalent Leptospira bacterin protects against infection and shedding following challenge in dogs // Vet Rec. 2013 Feb 16;172(7):181. doi: 10.1136/vr.101100. Epub 2012 Nov 23.

4. Boey K, Shiokawa K, Rajeev S. Leptospira infection in rats: a literature review of global prevalence and distribution // PLoS Negl Trop Dis. 2019;13:e0007499.

5. Ko AI, Goarant C, Picardeau M. Leptospira: the dawn of the molecular genetics era for an emerging zoonotic pathogen // Nat Rev Microbiol. 2009 Oct;7(10):736-47. doi: 10.1038/nrmicro2208. PMID: 19756012; PMCID: PMC3384523.

6. Basel Badra, A. V. Svyatkovsky, and T. B. Kuzina. Immunological screening of canine leptospirosis in St. Petersburg using the microagglutination reaction from 1998 to 2006 // Veterinary Practice. 2006;2:10-15. (In Russ.)

7. V. A. Kuzmin, L. S. Vogel, K. S. Savenkov (et al.) / The etiological structure of leptospirosis in animals and humans in St. Petersburg // Issues of regulatory and legal regulation in veterinary medicine. – 2016. – No. 1. – Pp. 72-74. (In Russ.)

8. Kindras T.M. Epizootiology and prevention of leptospirosis in dogs in the city // Pathogenesis, diagnostics and treatment of bacterial diseases of small domestic animals: collection of reports / Biol. scientificpractical center "CHIN". 1996;issue 2:14-18. (In Russ.)

9. Taylor C, Brodbelt DC, Dobson B, Catchpole B, O'Neill DG, Stevens KB. Spatiotemporal distribution and agroecological factors associated with canine leptospirosis in Great Britain // Prev Vet Med. 2021;193:105407.

10. Levett PN. Leptospirosis // Clin Microbiol Rev. 2001 Apr;14(2):296-326. doi: 10.1128/CMR.14.2.296-326.2001. PMID: 11292640; PMCID: PMC88975.

11. Eric Klaasen HL, Adler B. Recent advances in canine leptospirosis: focus on vaccine development. Vet Med (Auckl). 2015 Jun 19;6:245-260. doi: 10.2147/VMRR.S59521. PMID: 30101111; PMCID: PMC6067773.

12. Kuzmin V.A., Danko Yu.Yu., Vogel L.S., et al. Epizootiological and epidemiological features of leptospirosis in St. Petersburg // Hippology and Veterinary Medicine. 2015;3(17):43-46. (In Russ.)

13. Stoyanova N.A. Epizootic situation on leptospirosis and its epidemic manifestations in the conditions of St. Petersburg / N.A. Stoyanova, B. Badra, N.K. Tokarevich, et al. // Mater. Mosk. nauch.-prakt. konf. On leptospirosis.-M.,2007. – P.62-63. (In Russ.)

14. Stoyanova, N. A. Immunological screening of leptospirosis in dogs in St. Petersburg / N. A. Stoyanova, N. K. Tokarevich // Russian Journal of Infection and Immunity. – 2018. – Vol. 8, No. 4. – P. 619. – EDN YWWKSL.

15. Aliev A.A., Omarova S.N. Review of the epizootic situation in St. Petersburg // Tez. dokl. International scientific and practical Congress / Actual problems of veterinary medicine. 2005. pp. 36-38. (In Russ.)

16. GOST 25386-91. Agricultural animals. Methods of laboratory diagnosis of leptospirosis. Group G 79. 30 p. (In Russ.)