Hendra virus: the facts
Wednesday September 2, 2009
Hendra virus (genus Henipavirus, family Paramyxoviridae) was first observed in 1994. It affects horses and humans and can be deadly for infected people.
Hendra virus history
The Hendra virus, not fully understood by authorities, first emerged in Australia in August and September when 13 horses died in the Brisbane suburb, Hendra. Two horses died in an allegedly unrelated outbreak in Mackay.
The horse Drama Series became the first recorded death from the virus. Two people became infected with the virus after contact with the mare.
One of them, well-known horse trainer Vic Rail died from the infection.
In October 1995 a Mackay farmer Mark Preston, 35, became the third person to be infected with the Hendra virus. He also died as a result. It was after this case that authorities discovered the initial August 1994 infection of two his horses and made a retrospective diagnosis.
There has been 12 outbreaks of the virus since 1994. Six people have become infected and four people have died. Thirty-four-year-old Ben Cuneen became the third person to die after he caught the virus from infected horses at the Redlands veterinary clinic in Brisbane in August 2008. Dr Alistair Rodgers is the fourth person to die after he contracted the disease from an infected horse at the Cawarral horse stud near Rockhampton yesterday.
The mortality rate for horses with Hendra virus is extremely high with 70 per cent of infected animals dying from the virus.
Management and symptoms
People are warned to avoid contact with blood, saliva and other bodily fluids from infected animals.
There is no evidence of human-to-human spread or human-to-horse spread of Hendra virus. The virus can spread through the body very quickly. Doctors have reported periods of just 24 hours between the first sign of symptoms and serious illness. The incubation period is estimated at around five to 14 days.
Symptoms of Hendra virus affect the respiratory system,, and resemble influenza and pneumonia. The virus can affect the brain as well as encephalitis (swelling of the brain) type symptoms such as headaches, high fever and drowsiness, which can lead to convulsions and coma.
While there is no vaccine against the virus presently, scientists are working to develop one.
Study
Authorities including the Commonwealth Scientific and Industrial Research Organisation (CSIRO) and the Queensland Department of Primary Industries (DPI) have conducted studies that show the virus is commonly spread by fruit bats.
They are natural carriers of the virus and they are believed to spread the virus through their urine, faeces and reproductive fluid.
Authorities in Australia do not think that the virus is highly contagious in people.
However because all six cases of human infection have been in people who have close contact with infected horses, strict quarantine guidelines have been implemented.
