Leptospira seroprevalence and associated risk factors in healthy Swedish dogs

Abstract

Background Leptospirosis is an emerging zoonotic infection worldwide and a cause of life-threatening disease in dogs. Seroprevalence in Swedish dogs is unknown. The aims of the present study were to estimate seroprevalence of pathogenic Leptospira in healthy dogs in Sweden using the microagglutination test (MAT) and a rapid point-of-care enzyme-linked immunosorbent assay (ELISA), and to evaluate risk factors of Leptospira exposure in Swedish dogs. Results Positive MAT titres (≥ 1:50) were detected in 27/369 (7.3%) of included dogs. Five different serovars were represented of which the Saxkoebing serovar was the most common (64.3%), followed by Copenhagi (14.3%), Bratislava (10.7%), Icterohaemorrhagiae (7.1%), and Canicola (3.6%). The ELISA test (SNAP® Lepto) was positive in 3/316 (0.9%) dogs. Living in urban areas and contact with stagnant water were found to be risk factors for Leptospira seropositivity (p < 0.05) in a multivariable logistic regression model. Conclusion In this first seroprevalence study of Leptospira in Swedish dogs, it was shown that healthy dogs without recent (24 months) travel history and antileptospira vaccination had been exposed to pathogenic Leptospira interrogans serovars. Contact with stagnant water and living in urban areas were independent risk factors for seropositivity.

Leptospira Status in Sweden during the Past Century, Neglected and Re-Emerging?

“…In a recent seroprevalence study of Leptospira in healthy Swedish dogs, 27/369 (7.3%) had MAT titres ≥ 1:50, indicating previous exposure to Leptospira Interrogans serovars [ 51 ].…”

“…In Sweden, vaccination of dogs against leptospirosis is nowadays recommended for dogs travelling outside the country and/or visiting areas with known or suspected exposure to Leptospirosis. The vaccine used is a quadrivalent vaccine against four serogroups: Canicola, Icterohemorrhagiae, Australis, and Grippotyphosa (https://www.sva.se/amnesomraden/djursjukdomar-a-o/leptospiros-hos-hund/, accessed on 26 June 2023 [51]). An expert panel gathered by the International Society of Companion Animal Infectious Diseases (ISCAID) has recently prepared excellent guidelines and European consensus statements providing details about both treatment and vaccination of dogs (https://www.iscaid.org/guidelines/, accessed on 26 June 2023).…”