Prevalence of anti-leptospiral antibodies and frequency distribution of Leptospira serovars in small ruminants in enzootic South Peninsular India

Vet World Vol.14 August-2021 Article-6

Research Article

Veterinary World, 14(8): 2023-2030

https://doi.org/10.14202/vetworld.2021.2023-2030

Vinayagamurthy Balamurugan¹, Anusha Alamuri¹, Kirubakaran Vinod Kumar¹, Bibitha Varghese¹, Gurrappanaidu Govindaraj¹, Divakar Hemadri¹, and Parimal Roy^1,2

1. Indian Council of Agricultural Research-National Institute of Veterinary Epidemiology and Disease Informatics, Yelahanka, Bengaluru, Karnataka, India.
2. Centre for Animal Health Studies, TANUVAS, Madhavaram Milk Colony, Chennai, Tamil Nadu, India.

Background and Aim: For understanding the epidemiology of leptospirosis, the confined abundance of several species of pathogenic leptospires and knowledge on the serovar(s) prevalent in the reservoir and carrier hosts may be a useful indicator of transmission to incidental/accidental hosts in a geographical niche. The present study was carried out to ascertain the frequency distribution of Leptospira serovars and the prevalence of anti-leptospiral antibodies in small ruminants (sheep and goats) in the epidemiological units (villages) in the coastal districts of enzootic regions in South Peninsular India.

Materials and Methods: A total of 1167 serum samples (sheep n=299 and goats n=868) from apparently healthy animals, randomly collected from various epidemiological units were tested in microscopic agglutination test (MAT) using 18 reference Leptospira serovars antigens.

Results: The overall seroprevalence of 40% (at 95% confidence intervals [CI]: 36.82-42.43) in small ruminants (44% [95% CI: 40.49-52.26] in sheep and 38% [95% CI: 34.96-41.41] in goats) was observed with the predominance of Icterohaemorrhagiae, Javanica, Australis, Hurstbridge, and Pyrogenes serogroup anti-leptospiral antibodies in the studied region. The Chi-squared test revealed that the presence of anti-leptospiral antibodies is significantly not independent (associated) across the administrative division (Chi-square=105.80, p<0.05) as well as for sheep (Chi-square=34.67, p<0.01) and goats (Chi-square=68.78, p<0.01). Among seropositive samples (n=462 reactors), the MAT was positive for more than one serovar in 73% of sheep (95/131) and 53% of goats (177/331), representing an overall 59% cross-reactive prevalence in small ruminants. The determined frequency distribution (varied among small ruminants) of the employed serovars representing major reactive serogroup was Icterohaemorrhagiae (29.87), Javanica (20.78), Australis (20.35), Hurstbridge (16.23), Pyrogenes (15.8), Djasmin (15.58), Bataviae (15.37), Autumnalis (14.5), Canicola (14.5), Hebdomadis (14.07), Shermani (13.64), Panama (13.42), Sejroe (12.77), etc.

Conclusion: This study indicates alarmingly high seroprevalence of leptospirosis in small ruminants with existing endemicity in the studied region in South Peninsular India. Further, these prevalent serovars in the administrative division may be of use in the reference panels of antigens in the MAT in both humans and animal disease diagnostic laboratories for effective and timely diagnosis of leptospirosis and to combat the challenges in public health. Keywords: leptospirosis; sheep and goats, seroprevalence, frequency distribution, serovars, microscopic agglutination test, South Peninsular India.

Keywords: leptospirosis; sheep and goats, seroprevalence, frequency distribution, serovars, microscopic agglutination test, South Peninsular India.

How to cite this article: Balamurugan V, Alamuri A, Kumar KV, Varghese B, Govindaraj G, Hemadri D, Roy P (2021) Prevalence of anti-leptospiral antibodies and frequency distribution of Leptospira serovars in small ruminants in enzootic South Peninsular India, Veterinary World, 14(8): 2023-2030.

Received: 30-03-2021 Accepted: 22-06-2021 Published online: 06-08-2021

Corresponding author: Vinayagamurthy Balamurugan E-mail: b.vinayagamurthy@icar.gov.in

DOI: 10.14202/vetworld.2021.2023-2030

Copyright: Balamurugan, et al. This article 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 you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. The Creative Commons Public Domain Dedication waiver (http:// creativecommons.org/publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated.