Volume: 57 Issue: 2
Year: 2026, Page: 330-336, Doi: https://doi.org/10.51966/jvas.2026.57.2.330-336
Received: April 21, 2026 Accepted: June 23, 2026 Published: June 30, 2026
Canine dirofilariosis caused by Dirofilaria repens is an emerging zoonotic concern in Kerala, India. The present study investigated the molecular prevalence of D. repens infection and associated risk factors among dogs in and around Palakkad district, Kerala. A total of 102 blood samples from dogs presented to the District Veterinary Centre, Palakkad, were examined for microfilariae using Leishman-stained thin blood smears, and host- and management-related data were collected via a structured questionnaire. Genomic DNA was extracted and PCR-amplified targeting a 209 bp fragment of the cytochrome oxidase subunit 1 (COI) gene specific to D. repens. Microscopy detected microfilariae in 19.61% (20/102) of samples, while PCR confirmed D. repens infection in 8.82% (9/102). Majority of the host-related factors, including age, sex, breed, fever, deworming, and vaccination status, did not show a statistically significant association with D. repens infection (p>0.05). However, environmental exposure was significantly associated with positivity, with outdoor dogs showing a higher prevalence than indoor dogs (p<0.05). Sequencing and BLAST analysis confirmed species identity, and phylogenetic analysis revealed close clustering of the study isolate with Indian D. repens isolates from animals and humans, highlighting its zoonotic potential. The findings reaffirm the endemicity of D. repens in Kerala and emphasise the role of vector exposure in disease transmission.
Keywords: Dog, Microfilariae, Dirofilaria repens, PCR
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© 2026 Eravaramkunnath et al. This is an open access article distributed under the terms of the Creative Commons Attribution 4.0 International License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
Eravaramkunnath, F., Bal, M.S., Gupta, T., Vijayakumar, D. and Filia, G. 2026. Dirofilaria repens infection in Dogs and associated risk factors from an Endemic Region of Kerala: A Molecular Study. Journal of Veterinary and Animal Sciences, 57(2),330-336 https://doi.org/10.51966/jvas.2026.57.2.330-336