Carrier Status of Leptospira spp. in Healthy Companion Dogs in Sri Lanka

• Published in: Vector borne and zoonotic diseases (Larchmont, N.Y.) Vol. 22; no. 2; p. 93
• Main Authors: Athapattu, Tarindi, Fernando, Ruchika, Abayawansha, Roshan, Fernando, Palika, Fuward, Manohari, Samarakoon, Nishanthi, Koizumi, Nobuo, Gamage, Chandika
• Format: Journal Article
• Language: English
• Published: United States 01-02-2022
• Subjects: Animals; Dog Diseases - epidemiology; Dog Diseases - microbiology; Dogs; Leptospira; Leptospirosis - epidemiology; Leptospirosis - veterinary; Pets; Phylogeny; Sri Lanka - epidemiology; Sri Lanka; canine leptospirosis; chronic carrier; Sri Lanka; asymptomatic; zoonotic disease
• ISSN: 1557-7759
• DOI: 10.1089/vbz.2021.0065

Dogs are asymptomatic chronic carriers of
spp. and excrete these bacteria in their urine, resulting in environmental contamination and potentially leading to zoonotic transmission. Although a previous study in Sri Lanka detected anti-
antibodies in companion dogs, the urinary shedding of
spp. and the
species and serogroups prevalent in them remain unclear. Thus, the current study identified the prevalent
serogroups and the carrier status of
spp. in apparently healthy, client-owned dogs in the Kandy District of Sri Lanka. Serum and urine samples were collected from 96 unvaccinated and 82 vaccinated dogs. Anti-
antibodies and
DNA in urine were detected using the microscopic agglutination test (MAT) and nested PCR that targeted the pathogenic leptospiral gene,
. The
sequences were compared with those of
spp. using the public databases. MAT detected anti-leptospiral antibodies in 15.6% (15/96) of the unvaccinated dogs, and the reactive serogroups were observed to be Sejroe (11.5%), Canicola (2.1%), Icterohemorrhagiae (1.0%), and Javanica (1.0%). Furthermore, MAT results revealed that 11.0% (9/82) of the vaccinated dogs tested positive for the anti
antibodies and the only reactive serogroup was Sejroe.
DNA was detected in 15.6% (15/96) and 15.9% (13/82) of urine samples collected from unvaccinated and vaccinated dogs, respectively, and phylogenetic analysis revealed that the animals were infected with
,
,
, and
. The
sequence detected in the canine sample was identical to the one that was previously reported in a human sample from the Kandy District. This study demonstrated that both unvaccinated and vaccinated dogs excrete various pathogenic
spp. in their urine, suggesting that they may play an important role in environmental contamination that poses a health risk to the dog owners and the general public.