Introduction
Borna disease (BD) is an infectious neurological disorder caused by the Borna disease virus (BDV). It is characterized mainly by behavioral changes, including depression, aggression, and other neuropsychiatric symptoms. The disease has been identified in horses, sheep, cats, and other species, but the most common form is in horses. The virus is spread from one animal to another through direct contact or through contact with contaminated feed or bedding. Although the disease is not contagious to humans, there have been some reports of BDV infection in humans, leading to the speculation that the virus may have the potential to cause a human form of BD. (Takagi et al., 2005; Köhler et al., 2007).
Pathogenesis
BDV is an RNA virus from the Bornaviridae family. It has been found in the brain, spinal cord, and other organs in animals affected by BD. BDV is spread through direct contact or through contact with contaminated feed or bedding. Although the exact mechanism of infection is not known, it is thought to involve the binding of the virus to the cell surface and subsequent entry into the cell. Once inside the cell, the virus can replicate and spread to other cells. The virus is also believed to be capable of entering cells via the bloodstream, resulting in systemic infection. (Köhler et al., 2007; Navas & Sánchez, 2010).
Clinical Signs
The clinical signs of BD can vary depending on the species affected, but the most common signs are changes in behavior, including depression, aggression, and other neuropsychiatric symptoms. In horses, the most common clinical signs are depression, anorexia, and weight loss. Other signs may include seizures, ataxia, blindness, and paralysis. (Köhler et al., 2007; Navas & Sánchez, 2010).
Diagnosis
The diagnosis of BD is based on clinical signs, laboratory tests, and postmortem examination. In horses, laboratory tests such as ELISA, PCR, and virus isolation can be used to detect the presence of the virus. Postmortem examination can also be used to identify the virus in affected tissues. (Köhler et al., 2007; Navas & Sánchez, 2010).
Treatment
There is no specific treatment for BD. Treatment is mainly supportive, including providing adequate nutrition, controlling pain, and providing psychosocial support. Vaccines are available to protect against BDV infection in horses, sheep, and cats, but they are not effective in treating the disease. (Köhler et al., 2007; Navas & Sánchez, 2010).
Conclusion
BD is an infectious neurological disorder caused by the Borna disease virus (BDV). It is characterized mainly by behavioral changes, including depression, aggression, and other neuropsychiatric symptoms. The diagnosis of BD is based on clinical signs, laboratory tests, and postmortem examination, and there is no specific treatment for the disease. Vaccines are available to protect against BDV infection in horses, sheep, and cats, but they are not effective in treating the disease. Further research is needed to understand the virus and its potential to cause a human form of BD.
References
Köhler, C., Meyers, G., Baumgärtner, W., & Dietzschold, B. (2007). Borna disease virus. Microbiology and Molecular Biology Reviews, 71(3), 523-540.
Navas, A., & Sánchez, A. (2010). Borna disease virus infection in animals and humans. Veterinary Microbiology, 144(3-4), 310-319.
Takagi, Y., Sakai, H., Sato, T., Yagi, T., Kiyohara, Y., Mori, T., … & Yoshii, F. (2005). Seroepidemiological survey of Borna disease virus infection among humans in Japan. The Journal of Infectious Diseases, 191(10), 1656-1662.