Plague

Plague is a rare disease caused by the bacterium Yersinia pestis. People are usually infected through the bite of an infected flea or by handling an infected animal.

In the Middle Ages, millions of people in Europe died from plague because there were large numbers of infected rats, poorer hygiene practices and living conditions and a lack of antibiotic treatment. Today, plague is rare but can occur in some parts of the world.

Plague can cause different forms of illness that can affect the lymph glands (bubonic plague), the lungs (pneumonic plague) and the bloodstream (septicaemic plague).

Risk of plague infection

Plague is not established in Australia. People are most at risk if they have contact with infected rodents, their fleas or other infected animals in areas where plague occurs. Plague persists in some rural areas of Africa, Asia and the Americas.

How plague spreads

Plague is usually spread through the bite of an infected flea or direct contact with the blood or tissues of an infected animal.

Plague that results in lung infection (pneumonic plague) can potentially spread when a person breathes in respiratory droplets from an infected person or animal. This is the only form of plague that can spread from person to person. This rarely occurs and usually requires close contact with the infected person or animal.

Symptoms of plague

Symptoms usually begin within one to seven days of exposure, depending on the form of plague.

Early symptoms include

• fever
• chills
• headache
• nausea and vomiting
• body aches and weakness.

Different forms of plague can also result in other symptoms:

• Plague that affects the lymph glands (bubonic plague) is the most common. It results in swollen and tender glands closest to the bite from the infected flea.
• Plague that results in lung infection (pneumonic plague) can cause fever, shortness of breath, chest pain, cough, and sometimes bloody or watery mucus.
• Plague that results in bloodstream infection (septicaemic plague) can cause abdominal pain, shock, bleeding into the skin or other organs, and tissue damage.
• Plague can progress quickly and cause severe illness or even death if treatment is not started quickly.

Prevention of plague

There is no vaccine to protect against plague. The risk can be reduced by avoiding contact with fleas, rodents and other animals that may be infected.

Most Australians are not at risk of plague. When travelling overseas in areas with plague:

• avoid direct contact with fleas, rodents and other animals
• use insect repellent during outdoor activities (such as camping and hiking)
• repellents with DEET can be used on skin
• repellents with permethrin can be used on clothing
• do not let dogs or cats that roam outside sleep on beds and limit contact with them where possible.
• wear gloves if you need to handle animals that could be infected.

Controlling rodent populations helps lower flea numbers and reduces the risk of plague spreading to people.

Diagnosis and treatment of plague

Plague is diagnosed by testing samples such as blood, sputum or fluid from a swollen lymph gland for Yersinia pestis.

Plague is treated with antibiotics which should be started quickly.

People who have had close contact with someone with the lung infection form of plague (pneumonic plague) may be offered preventive antibiotic treatment by public health authorities and be advised to look out for symptoms.

Where to get help

• In an emergency, always call triple zero 000
• Emergency department of your nearest hospital
• Virtual Emergency Department
• Urgent Care Clinics – when immediate healthcare is needed but it's not life-threatening
• Your GP (doctor)
• Nurse-on-Call - 1300 606 024 – for expert health information and advice (24 hours, 7 days)
• Find your Local Public Health Unit
• Communicable Disease section, Department of Health, Victorian Government Tel. 1300 651 160