7. CANINE LEPTOSPIROSIS: POLYMERASE CHAIN REACTION AS A RAPID ALTERNATIVE TO CONVENTIONAL TECHNIQUES

Leptospirosis is an acute febrile zoonotic disease with worldwide distribution and has become an important global health concern. The disease is endemic in southern parts of India, especially in Kerala. The laboratory diagnosis of leptospirosis is based on bacteriological, molecular and serological detection methods. The present study was envisaged to compare the molecular techniques for detection of leptospires with the traditional isolation and serological methods. Out of 100 blood samples tested, 27 were found to be positive for microscopic agglutination test (MAT) and from eight samples, leptospires could be isolated successfully in Ellinghausen- McCullogh-Johnson-Harris media (EMJH). MAT positive samples when subjected to polymerase chain reaction (PCR) targeting the lipl32 gene of Leptospira, two samples gave positive amplicons of about 767 bp. Even though, the gold standard test for diagnosisof leptospirosis is isolation and identification of the causative organism, it is laborious, time consuming and requires technical expertise. Thus, the present study recommends the use of MAT for the identification of infecting serovars of Leptospira, while PCR forms an effective tool to provide a rapid diagnosis, particularly in acute infections.

Key words: Leptospirosis, isolation, Microscopic agglutination test, Polymerase chain reaction, lipl32, EMJH, Canine, Kerala.