avian & livestock assay data sheet

Borna virus

Test code: S0207 - Ultrasensitive qualitative detection of Borna virus by reverse transcription coupled real time polymerase chain reaction

Borna disease virus (BDV) is an enveloped nonsegmented negative-strand RNA virus with a genome size of about 9 kb. The virus is of member of the Mononegavirales order. The Mononegavirales also include Filoviridae (eg Marburg and Ebola viruses), Paramyxoviridae (eg mumps, measles virus), and Rhabdoviridae (eg rabies, vesicular stomatitis virus).

This viral disease was first described more than 200 years ago in a small town named Borna in Saxony in southern Germany. It is a fatal neurologic disease of horses and sheep. A large number of horses died during an epidemic in 1885. Although outbreaks of Borna disease are rare, serological survey has indicated that many horses in various geographic regions have been exposed to the virus. This suggests that natural infection of horses with this virus may be subclinical.

Although horses are the natural host of the virus, other equidae, sheep, cattle, rabbits, goats, deer, alpacas, llamas, cats, pygmy hippopotamus and sloths can be infected with BDV. The virus is transmitted by direct contact with saliva, nasal discharge or conjunctival secretions of infected animals.  Direct exposure to contaminated food or water can also be a source of infection.

Infected horses or sheep usually take about 4 weeks to show signs of infection, but the signs are non-specific. These signs include hyperthermia, anorexia, colic, and constipation in the initial phase of the disease. During the acute phase, neurologic signs such as ataxia, depression, circular movement, standing in awkward positions, collapsing, running into obstacles, and paralysis, may develop. Clinical symptoms last 1 to 3 weeks, and death rates for diseased horses are 80% to 100%.

Diagnosis of Borna disease can be by serological methods or by molecular methods such as polymerase chain reaction. PCR is rapid, sensitive and specific (Wensman et al., 2012), and does not require infected animals to develop full immune responses. Thus, PCR is especially suitable for early detection of the virus.

Utilities:

• Help confirm the disease causing agent
• Identify Borna virus carriers
• Help ensure that animal herds and populations are free of Borna virus
• Early prevention of spread of this virus among animals
• Minimize human exposure to this virus
• Safety monitoring of biological products that derive from animals

References:
Wensman, J.J., Jäderlund, K.H., Gustavsson, M.H., Hansson-Hamlin, H., Karlstam, E., Lilliehöök, I., Oström, I.L., Belák, S., Berg, M. and Holst, B.S. (2012) Markers of Borna disease virus infection in cats with staggering disease. J. Feline Med. Surg. 14:573-582.

Specimen requirements: 0.2 ml whole blood in EDTA (purple top) tube, or 0.2 ml feces, or oral swabs, or nasal swabs, or 0.2 ml fresh or frozen tissue.

Contact Zoologix if advice is needed to determine an appropriate specimen type for a specific diagnostic application. For specimen types not listed here, please contact Zoologix to confirm specimen acceptability and shipping instructions.

For all specimen types, if there will be a delay in shipping, or during very warm weather, refrigerate specimens until shipped and ship with a cold pack unless more stringent shipping requirements are specified. Frozen specimens should be shipped so as to remain frozen in transit. See shipping instructions for more information.

Turnaround time: 2 business days

Methodology: Qualitative reverse transcription coupled real time PCR

Normal range: Nondetected