Akabane virus NOTE: THIS TEST IS NOT PERFORMED ON SAMPLES TAKEN FROM ANIMALS OWNED OR LOCATED IN THE STATE OF CALIFORNIA.

Test code: S0199 - Ultrasensitive detection of Akabane virus by reverse transcription coupled real time PCR

Akabane virus is an insect-transmitted virus that causes congenital abnormalities of the central nervous system in ruminants. The virus belongs to the family Bunyaviridae and is spread by biting midges (Culicoides spp).  There are a number of different strains of the virus including Tinaroo virus, Sabo virus and Yaba-7 virus. The various strains of Akabane virus may differ considerably in their virulence.

Akabane virus has been detected in many tropical and subtropical areas. Disease due to Akabane virus has been reported in Australia, Israel, Kenya, Japan, and Korea; antibodies to it have been found in a number of countries in Southeast Asia, the Middle East, and Africa. In these endemic areas, herbivores are bitten by the vector insect, become infected at an early age, and develop a long-lasting immunity by the time of breeding. Fetal congenital abnormalities are therefore seldom seen. However, under some environmental conditions such as an extended humid summer, the insect vector may spread into new areas, and outbreaks of congenital infection are then seen in those areas.

The disease affects fetuses of cattle, sheep, and goats. Asymptomatic infection has been demonstrated serologically in horses, buffalo, and deer (but not in humans or pigs) in endemic areas. Not all infections result in congenital abnormalities and the incidence rate is determined by the time of gestation at which infection occurs and also by the strain of virus. Infections in cattle during the last 3 months of pregnancy result in approximately 5–10% affected calves. Peak incidence is seen when infection occurs in the third and fourth months of pregnancy; up to 40% of calves of mothers infected at this stage of pregnancy may be born with defects.

Sheep and goats infected with this virus do not have the same sequential manifestation of different abnormalities seen in cattle because of the shorter period of gestation and the shorter period of susceptibility.

Diagnosis of the disease is often confirmed by necropsy.  Serology has been used but is not very sensitive. However, molecular detection by PCR is highly sensitive, specific and rapid.

Utilities:

• Help confirm the disease causing agent
• Shorten the time required to confirm a clinical diagnosis of Akabane virus infection
• Help ensure that animal herds and populations are free of akabane virus
• Early prevention of spread of the virus among animals
• Minimize human exposure to the virus
• Safety monitoring of biological products that derive from animals

References:
Kamata, H., Inai, K., Maeda, K., Nishimura, T., Arita, S., Tsuda, T. and Sato, M. (2009) Encephalomyelitis of cattle caused by Akabane virus in southern Japan in 2006. J. Comp. Pathol. 140:187-193.

Specimen requirements: 0.2 ml whole blood in EDTA (purple top) tube, 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