[Antibody titers against Borrelia in horses in serum and in eyes and occurrence of equine recurrent uveitis].

The research is an investigation into the correlation between antibodies to Borrelia burgdorferi, a type of bacteria, and cases of equine recurrent uveitis (ERU), a disease affecting the eyes of horses. Antibody levels of B. burgdorferi were measured in horses with and without observable eye diseases, but there was no notable connection found between elevated antibody levels and ARI symptom occurrence.

Background and Objective of the Study

• The research addresses a gap in Germany regarding the knowledge of the presence and impact of B. burgdorferi antibodies in horses. In contrast, in the USA, there are significant studies on the infection and its symptoms such as lameness, fever, pneumonia, etc. A relevant study in the U.S. showed a possible link between panuveitis, a severe inflammatory eye condition, and Borrelia infection in horses.
• B. burgdorferi infection’s implications in human medicine, specifically its connection to uveitis and other eye diseases, also fueled the study. The primary objective of the research was to determine any association between B. burgdorferi antibodies and ERU occurrences.

Methodology

• To achieve this, the researchers identified the antibody titer, a measure of the concentration of antibodies in the blood, against B. burgdorferi in 153 horses with no signs of eye disease and in 79 horses with ERU. This procedure was done using Immuno-Fluorescence Test (IFT).
• Apart from using the IFT method, western-blot technique was also employed to test 22 sera for antibody titers.

Research Findings

• The study found that 48% of all horses had positive titers, indicated by a titer of 1:64 or higher, but there was no significant correlation between signs of ERU and increased antibody titers against B. burgdorferi.
• Horses with elevated titers did not exhibit any clinical signs of disease. Furthermore, no correlation was found between the horses’ age and the detected antibody levels.
• Interestingly, the research noticed a connection between the month of examination and the antibody titer, with highest titer levels seen in May and November, a month after the activity peak of the transmitting ticks (I. ricinus).