equine assay data sheet

Hendra virus (HeV) NOTE: THIS TEST IS NOT PERFORMED ON CLINICAL SAMPLES TAKEN FROM HORSES OWNED OR LOCATED IN THE STATE OF CALIFORNIA.

Test code: S0273 - Ultrasensitive qualitative detection of Hendra virus by reverse transcription coupled real time polymerase chain reaction

Hendra virus (HeV) is a rare, zoonotic (animal-to-human) virus that causes severe and often fatal disease in horses and humans. It belongs to the genus Henipavirus in the family Paramyxoviridae, the same family as the related Nipah virus. Hendra virus has a non-segmented, negative-sense, single-stranded RNA genome typical of the family. The genome size is about 18 kb.

The virus was first identified in 1994 during an outbreak in the Brisbane suburb of Hendra, Australia. It is found only in Australia, where it is maintained in nature by fruit bats (flying foxes) of the genus Pteropus. These bats are the natural reservoir and typically do not show symptoms. Horses become infected through contact with bat urine, saliva, droppings, or contaminated fruits and plants. Humans get infected through close contact with sick horses, particularly exposure to their respiratory secretions, blood, or other bodily fluids during handling, veterinary care, or necropsy. There is no documented human-to-human transmission, and horse-to-horse transmission is limited.

When horses are infected with the virus, they can develop a sudden onset of fever, depression, rapid breathing, nasal discharge, neurological signs such as ataxia, tremors, and head tilt, followed by rapid deterioration. Many cases are fatal. In humans; the infection initially presents with flu-like symptoms such as fever, headache, cough, sore throat, tiredness, and myalgia. However, the symptoms can progress rapidly to severe respiratory illness or neurological disease including encephalitis or meningitis, with drowsiness, confusion, seizures, or coma.

There is no specific approved antiviral treatment for humans, so supportive care in an intensive care unit is often the main approach. Vaccination of horses is the best method of preventing the disease.

Diagnosis of the viral infection by viral culture is very slow and requires high-containment facilities. Serological methods may not be suitable for acute disease detection as it takes time for antibodies to develop. PCR is often used to detect the virus due to its high specificity and sensitivity (Feldman et al., 2009; Smith et al., 2001).

Utilities:

• Help ensure that horse populations are free of Hendra virus
• Early prevention of spread of this virus
• Minimize personnel exposure to this virus
• Safety monitoring of biological products that derive from horses

References:
Feldman KS, Foord A, Heine HG, Smith IL, Boyd V, Marsh GA, Wood JL, Cunningham AA, Wang LF. Design and evaluation of consensus PCR assays for henipaviruses. J Virol Methods. 2009 Oct;161(1):52-7.

Specimen requirements: 0.2 ml whole blood in EDTA (purple top) tube, or nasal swab, or oropharyngeal swab, or rectal mucosal swab, or 0.2 ml feces, or 0.2 ml urine, or urine soaked swab, or 0.2 ml cell culture, 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