Evaluation of Two Serologic Tests for Rapid Detection of Anti-Leptospira Antibodies in California Sea Lions
- Infectious disease
- Leptospirosis
Abstract
Leptospirosis is a bacterial zoonosis impacting wild and domestic animals globally. Leptospira interrogans serovar Pomona is endemic in free-ranging California sea lions (CSLs; Zalophus californianus), and leptospirosis is frequently diagnosed in stranded CSLs. Serum microscopic agglutination test (MAT) is a commonly performed diagnostic assay, and CSLs with clinical disease have reliably elevated MAT titers. However, MAT results may not be available for several days after sampling. Given the zoonotic and high transmission potential of Leptospira spp., a point-of-care diagnostic test would be valuable in rehabilitation and managed care settings and during outbreak response efforts. The ID SNAP and Zoetis WITNESS anti-Leptospira antibody tests are rapid diagnostic tools that have been validated in dogs and give a qualitative (positive or negative), not quantitative (exact titer), result. The SNAP test uses ELISA to detect both immunoglobulin (Ig)M and IgG antibodies, whereas the WITNESS test is a lateral flow assay that only detects IgM. We compared SNAP and WITNESS results with MAT results by using serum collected from stranded and free-ranging CSL with negative, low, medium, and high anti-Leptospira antibody titers as previously determined by MAT. Percent agreement between SNAP and MAT results was high, with a Cohen’s kappa statistic of 0.957. No WITNESS tests were positive. These findings suggest that the SNAP test may be useful for detecting antiLeptospira antibodies and ruling out leptospirosis in CSL.
Peters, M., Field, C.L., Hortensius, L.M., Soper, J., Burco, J., Kelly, T.R. and Prager, K.C., 2025. Evaluation of Two Serologic Tests for Rapid Detection of Anti-Leptospira Antibodies in California Sea Lions (Zalophus californianus). Journal of Wildlife Diseases. 2025.
leptospirosis
Cara Field
Lian Hortensius
infectious disease, leptospirosis, California sea lion, Lepto SNAP, Lepto WITNESS, Leptospira, microscopic agglutination test, Zalophus californianus.
Meet The Experts
{"image":"\/People\/Portrait\/cara-field.jpg","alt":"Cara Field","title":"Cara Field","text":"Director, Conservation Medicine","link_url":"https:\/\/www.marinemammalcenter.org\/person\/cara-field","link_text":"Read Bio"}
{"image":"\/People\/Portrait\/lian-hortensius.jpg","alt":"Lian Hortensius","title":"Lian Hortensius","text":"Director, Animal Data Science","link_url":"https:\/\/www.marinemammalcenter.org\/person\/lian-hortensius","link_text":"Read Bio"}
Related Publications
{"image":"\/Animals\/Wild\/Other species\/nz-sea-lion-shutterstock.jpg","alt":"New Zealand sea lion","title":"Causes of Death in Two Populations of New Zealand Sea Lions","link_url":"https:\/\/www.marinemammalcenter.org\/publications\/causes-of-death-in-two-populations-of-new-zealand-sea-lions","label":"Research Paper"}
{"image":"\/Animals\/Patients\/California sea lions\/csl-by-bill-hunnewell-c-the-marine-mammal-center-6.jpg","alt":"California sea lions","title":"Zoonotic Bacteria Persistence and Susceptibility","link_url":"https:\/\/www.marinemammalcenter.org\/publications\/zoonotic-bacteria-persistence-and-susceptibility","label":"Research Paper"}
{"image":"\/Animals\/Patients\/California sea lions\/cropped-images\/csl-photo-by-bill-hunnewell-c-the-marine-mammal-center-1-0-0-2358-1722-1600891644.jpg","alt":"California sea lions","title":"Emerging Viruses in Marine Mammals","link_url":"https:\/\/www.marinemammalcenter.org\/publications\/emerging-viruses-in-marine-mammals","label":"Research Paper"}
{"image":"\/Animals\/Patients\/California sea lions\/csl-photo-by-bill-hunnewell-c-the-marine-mammal-center-12.jpg","alt":"two California sea lions","title":"Multi-Phase Muscle Breakdown in California Sea Lions","link_url":"https:\/\/www.marinemammalcenter.org\/publications\/multi-phase-muscle-breakdown-in-california-sea-lions","label":"Research Paper"}
Recent News
{"image":"\/People\/Action\/Veterinary care\/cropped-images\/dane-whitaker-and-emily-whitmer-vaccine-trial-by-bill-hunnewell-49-0-1270-992-1757364612.jpg","alt":"Two veterinarians collect a blood sample from an elephant seal in a rehabilitation pen.","title":"Bird Flu Vaccine Trial May Offer Hope for Protecting Hawaiian Monk Seals","link_url":"https:\/\/www.marinemammalcenter.org\/news\/bird-flu-vaccine-trial-may-offer-hope-for-protecting-hawaiian-monk-seals","label":"News Update","date":"2025-09-09 09:13:00"}
Bird Flu Vaccine Trial May Offer Hope for Protecting Hawaiian Monk Seals
September 9, 2025
Read More{"image":"\/Animals\/Patients\/Elephant seals\/2025\/cropped-images\/es-vaccine-trial-satellite-tag-by-bill-hunnewell-218-0-1270-992-1757432410.jpg","alt":"Northern elephant seal","title":"The New York Times: Scientists Begin Testing Bird Flu Vaccine in Seals","link_url":"https:\/\/www.marinemammalcenter.org\/news\/the-new-york-times-scientists-begin-testing-bird-flu-vaccine-in-seals","label":"In the News","date":"2025-09-09 02:00:00"}
The New York Times: Scientists Begin Testing Bird Flu Vaccine in Seals
September 9, 2025
Read More{"image":"\/Animals\/Patients\/Sea otters\/2025\/cropped-images\/so-mooring-release-2-laurie-miller-c-the-marine-mammal-center-USFWS-permit-MA101713-1-80-0-1270-992-1757003194.jpg","alt":"A southern sea otter rests in the ocean after being released from rehabilitative care.","title":"Entangled in Ocean Trash, Sea Otter Mooring Gets a Second Chance at Life","link_url":"https:\/\/www.marinemammalcenter.org\/news\/entangled-in-ocean-trash-sea-otter-mooring-gets-a-second-chance-at-life","label":"Patient Update","date":"2025-09-05 02:00:00"}
Entangled in Ocean Trash, Sea Otter Mooring Gets a Second Chance at Life
September 5, 2025
Read More{"image":"\/Animals\/Patients\/Harbor seals\/2025\/cropped-images\/denali-hs-photo-by-clive-beavis-c-the-marine-mammal-center-79-0-1270-992-1756314221.jpg","alt":"2026 marine mammal center calendar cover star","title":"Pacific Harbor Seal Denali Chosen as the 2026 Calendar Cover Star","link_url":"https:\/\/www.marinemammalcenter.org\/news\/vote-for-your-favorite-marine-mammal-to-be-the-2026-calendar-cover-star","label":"News Update","date":"2025-08-04 02:00:00"}
Pacific Harbor Seal Denali Chosen as the 2026 Calendar Cover Star
August 4, 2025
Read More