Topic: Anthrax
Description
Anthrax is a disease caused by bacteria carried by wild and domestic animals that eat plants. These bacteria can form spores, which allows the bacteria to survive in the environment. People can then become infected with anthrax by handling products from infected animals or by breathing in anthrax spores from infected animal products (like wool, for example). People also can become infected with gastrointestinal anthrax by eating undercooked meat from infected animals. Anthrax is now rare in Australia. The last human case of anthrax in Australia occurred in 1998 and was work related.
Symptoms
Symptoms usually occur within seven days of exposure, but can occasionally be delayed for up to 60 days. There are three forms of disease in humans: lung (inhalation) anthrax, skin (cutaneous) anthrax and intestinal anthrax.
Lung anthrax is caused by breathing in large numbers of anthrax spores. Early symptoms are flu-like and can include fever, tiredness, mild cough or chest pain. After several days, the symptoms progress to severe breathing problems and shock.
Skin anthrax is a skin infection. Initially, an itchy lump occurs. Over one to two days, this develops into a blister and then into a painless ulcer with a black centre.
Intestinal anthrax may occur after eating food contaminated with anthrax. Symptoms include nausea, vomiting, abdominal pain and diarrhoea.
Transmission
People infected with anthrax, or who may have been exposed to anthrax, do not pose a risk to other people and it is extremely unusual for the disease to passed from person to person. Anthrax is not infectious.
Treatment
People who may have been exposed to anthrax can be treated with antibiotics. This usually prevents the onset of symptoms and disease.
Health Outcome
Emergency response plans are in place to protect the public in the unlikely event of a biological incident such as the release of anthrax. While there is no known specific threat to Australia, the possibility has been considered as part of Queensland Health's planning process. If anthrax contamination is detected in Queensland, people who are exposed will be informed by public health units and given advice on further management.
Prevention
A vaccine against anthrax has been manufactured in the USA, but it is used only in high risk occupational situations and needs to be specially imported to Australia. Vaccination requires six injections and yearly booster doses.
Control of anthrax in domestic livestock is important for preventing its spread to people. Animals dying from anthrax usually die suddenly, with only brief illness preceding death. A farmer who suspects anthrax in an animal must notify a government veterinary officer immediately. If anthrax is suspected, the farm will be isolated and herds vaccinated, and the dead animal disposed of appropriately so that contamination of the soil is minimised.
Anthrax vaccines exist for use in livestock in Australia, but are not currently registered for use in humans. Safety regulations covering rendering plants and factories processing wool and hides must be adhered to. Workers should also wear protective clothing.
Even a single case of human anthrax is so unusual in Australia that it should be reported urgently to your local public health unit.
Help and Assistance
If you have a serious concern that you have been exposed to an unidentified substance that may contain anthrax, dial 000.
Other Resources
Emergency Management Australia
Footnotes
Heymann, D., ed. 2004. Control of Communicable Diseases Manual, 18th edition. Washington, DC: American Public Health Association.
National Health and Medical Research Council, 2003. The Australian Immunisation Handbook (8th Ed.) Canberra: National Capital Printing.
Queensland Department of Primary Industry and Fisheries. Anthrax in live stock. File no APH0165.
Last Updated: 12th October, 2009
Date Valid to: 30th June, 2010
