Australian scientists tackle deadly Q fever

Scientists at James Cook University have taken the lead in developing a new vaccine against a highly infectious cattleyard disease caused by a bacteria which has the potential to be developed as a bioterrorist weapon.

JCU's Infectious Diseases and Immunopathogenesis Research Group, within the School of Veterinary and Biomedical Sciences, has secured a $300,000 grant from the Defence, Science and Technology Organisation (DSTO) in Melbourne to conduct research into Q fever over three years.

Research associate Ray Layton is one of a small team of scientists working on the groundbreaking project at JCU.

"The armed forces are very interested in this research because Coxiella burnetii, the species of bacteria which causes Q fever, is resistant to heat, drying and many disinfectants so it can survive for a long time. It can become airbourne very quickly and is therefore highly infectious," Mr Layton said.

"The possibilities for it to be developed as a Class 2 bioterrorist weapon are there. It is on a long list of agents that could become a risk with a lot of work. Our research will look at producing a vaccine that can be used to protect us against such a development.

"The last thing the Army can afford is for hundreds of soldiers to be out of action because they have had an adverse reaction to a vaccine."

Mr Layton said that Q fever was primarily an occupational hazard for workers from the meat and livestock industries. It is present in the milk, urine, faeces and, more significantly, the amniotic fluids and placenta of infected cattle, sheep and goats.

Infection in humans usually occurs through inhalation of airbourne organisms in barnyard dust and can result in high fever, muscle pain, confusion, vomiting and diarrhoea. Chronic Q fever can lead to endocarditis, an infection of one of the four heart valves, and can be fatal.

"It is the first time the University has looked at Q fever," Mr Layton said.."It's quite a coup as it means we are not only collaborating with all the other Q fever research groups in Australia but we are cemented at the forefront of that research because of our molecular biology skills and knowledge."

The JCU group is also the only Q fever research team in Australia to have a Physical Containment 3 laboratory, which enables scientists to work with highly infectious organisms in a secure environment. Having such a facility has helped form collaborative links with groups in Melbourne, Perth, Brisbane and Darwin.

The group's principal investigator, Brenda Govan, said the current Q fever vaccine was far from perfect. It cannot be administered to those under 15 and it can still be devastating to those that can have it.

People who have adverse reactions, most because they have an allergy to the chicken egg antigens used in the vaccine, can get an abscess at the point of injection, develop swollen joints and become feverish.

"What we are looking at is developing a new vaccine where, instead of being injected with egg antigens and killed Coxiella burnetii, people will simply be injected with the cloned proteins responsible for producing an immune response against the bacteria," she said.

"This should mean no more nasty side effects."

According to the Queensland Government there is an average of 229 reported cases of Q fever in the state each year. The name originates from the term 'query' fever which was applied to the disease when it was first seen in abattoir workers in Australia in 1933.

http://www.jcu.edu.au