Demonstration of continuously seropositive population against Borna disease virus in Misaki feral horses, a Japanese strain: a four-year follow-up study from 1998 to 2001.

The research study aims to monitor the presence of Borna disease virus (BDV) specific antibodies in the Misaki feral horses, a Japanese strain, over a period of 4 years, using an instrument called electrochemiluminescence immunoassay (ECLIA). The results established a consistently seropositive population, with 26.9% being BDV seropositive and the presence of p24 antibodies being frequently dominant than the p40 antibodies.

Methodology

• The research was conducted through an annual inspection over a period of 4 years to monitor the BDV-specific antibodies in Misaki feral horses.
• The method of monitoring was through the usage of an electrochemiluminescence immunoassay (ECLIA).
• There were altogether 130 horses that were examined for both p24 and p40 antibodies.

Findings

• Out of the 130 horses studied, 35 horses (26.9%) showed an ECLIA count exceeding 1000 at least once or more during the study, which led them to be judged as BDV seropositive.
• The p24 antibodies were found to be more frequent than p40 antibodies in nearly all the BDV-positive horses. This indicates that p24 antibodies may be more significant in the immune response to the BDV among these horses.
• Among the seropositive horses, the ECLIA count was observed to be consistently high over the course of the study in 12 cases. This suggests a persistent immune response to the BDV in these animals.
• In the study, 11 horses showed seroconversion from negative to positive, indicating that these animals were likely newly infected during the study period.
• Furthermore, 7 horses showed a reversal, going from seropositive to seronegative. This could be indicative of the individual animal’s immune system defeating the virus or the limitations in the sensitivity of the diagnostic test.
• The remaining 95 horses accounted for 73.1% of the sample, and their ECLIA-counts remained low for the duration of the 4-year study, suggesting they were seronegative for BDV.

Conclusion

• The study concluded with the detection of a consistently seropositive population against BDV among Misaki feral horses over the span of 4 years.
• This research contributes to understanding the prevalence and dynamics of BDV infection in these specific horse populations and helps in planning effective disease management strategies.