Plague is a rare disease caused by bacteria that are usually transmitted from infected rodents to humans through flea bites. Plague occurs in many countries outside Australia. Death is rare with prompt antibiotic treatment.

Last updated: 05 April 2024

What is plague?

Plague is a rare disease caused by the Yersinia pestis bacteria. It is spread from infected rodents to humans usually through flea bites. Plague was responsible for millions of deaths in Europe in the Middle Ages where large numbers of infected rats were in close contact with people and antibiotic treatment was not available. Today the disease is less common and death is rare with prompt antibiotic treatment.

What are the symptoms?

Early symptoms include fever, chills, headache, nausea and vomiting, body aches and weakness. Bubonic plague (the most common type) results in swelling and tenderness of the lymph node nearest to the flea bite (known as a "bubo"). The bacteria can enter the bloodstream (known as septicaemic plague) and the lungs (pneumonic plague) causing more severe illness. Symptoms usually occur from one to six days after coming into contact with the bacteria.

How is it spread?

Plague is usually spread from infected animals to humans through flea bites. Infection can also occur as a result of direct contact with infected animal materials. Rarely, human cases can occur after inhaling infectious respiratory droplets or other materials.

Who is at risk?

Plague is not found in Australia. People at risk are those in contact with rodents and their fleas in areas where plague is found. Wild rodent plague exists in rural parts of the Americas, the former Soviet Union, Africa and Asia (see the US CDC travel site​​ for further information).

How is it prevented?

A vaccine for plague is not available. Preventive measures are aimed at reducing contact with fleas and potentially infected rodents and other wildlife.

How is it diagnosed?

Plague is diagnosed by identifying the Yersinia pestis bacteria from the bubo, blood, spinal fluid or sputum.

How is it treated?

Early treatment with antibiotics is required.

What is the public health response?

Laboratories diagnosing cases of plague must notify the local public health unit. Public health units follow up each case to determine where the person acquired the infection and prevent further spread.

For further information please call your local public health unit on 1300 066 055

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