262438 Serological evidence of potential occupational exposure to leptospirosis in Kentucky horse farm workers and veterinarians

Tuesday, October 30, 2012

Gloria Gellin, MS, MPH , Agricultural Research Service, United States Department of Agriculture, Lexington, KY
Craig Carter, DVM, PhD , Veterinary Diagnostic Laboratory, University of Kentucky, Lexington, KY
Glyn G. Caldwell, MD , University of Kentucky College of Public Health, Lexington, KY
John Timoney, MVB, PhD , Gluck Equine Research Center, University of Kentucky, Lexington, KY
Margaret Steinman, MPH , Veterinary Diagnostic Laboratory, University of Kentucky, Lexington, KY
David Fardo, PhD , College of Public Health, Biostatistics, University of Kentucky, Lexington, KY
Wayne Sanderson, PhD , Department of Epidemiology, The University of Kentucky, Lexington, KY
  
Sera from employees and horses residing on farms affected (AF) by outbreaks of leptospirosis in Central Kentucky since 2006 were compared to farms unaffected (UF) by these outbreaks during this same time period. A total of six farms, three farms from each group, were compared (4 human subjects and 4 horses) for a total of 24 horses and 24 humans. Sera from a second group, veterinarians specializing in equine medicine (EV), were also analyzed. This group contained 24 veterinarians with a range of exposure levels from no known past exposure to individuals exposed five days previous to collection of sera. Each farm manager completed a survey assessing farm management of horses. In addition, veterinarians completed a survey regarding their equine medicine experience. Enzyme-linked immunosorbent assays (ELISA) showed an increased risk of seroconversion to Leptospira in 5 (22%) of 23 equine veterinarians compared to zero (0%) of 24 farm workers (p=0.05). Antibody levels for both sphingomyelinase 2 (Sph2) and leptospiral immunoglobulin-like protein A (LigA) were significantly increased (p=0.03 and p=0.05 respectively) in veterinarians. Indirect hemoagglutination (IHA) and microscopic agglutination (MAT) titers were negative for all individuals participating in the study. Risk for seroconversion did not appear to be influenced by the period of time from last exposure nor age of the individual. There is an increased risk for seroconversion to Leptospira, without the appearance of clinical disease, in EV compared to individuals working on Central Kentucky horse farms.

Learning Areas:
Basic medical science applied in public health
Clinical medicine applied in public health
Occupational health and safety

Learning Objectives:
1.Compare occupational exposure to leptospirosis between farm workers and veterinarians 2.Evaluate an investigational testing method to conventional techniques 3.Demonstrate an increased risk of seroconversion to leptospirosis in veterinarians

Keywords: Veterinary Public Health, Zoonoses

Presenting author's disclosure statement:

Qualified on the content I am responsible for because: I have been involved in clinical veterinary medicine and basic science research for over 30 years working on multiple federally and privately funded grants focusing on multiple areas of translational medicine. My scientific interests have been in antibiotic resistance in animals and zoonotic disease.
Any relevant financial relationships? No

I agree to comply with the American Public Health Association Conflict of Interest and Commercial Support Guidelines, and to disclose to the participants any off-label or experimental uses of a commercial product or service discussed in my presentation.

Back to: 4273.3: Emerging Infections: perspectives on zoonotic diseases in the near past and on the horizon to include unique zoonoses, MRSA in animals, hemorrhagic fevers, vector borne disease. etc