Plague

What is plague?

Plague is a disease that can spread from animals to humans. It is caused by the Yersinia pestis bacteria, usually found in small mammals (e.g. rodents) and their fleas.

There are three main forms of plague: bubonic plague, septicaemic plague, and pneumonic plague.

How is plague transmitted?

Humans usually become infected through:

• Bite of an infected flea

• Direct contact with infected animals

• Inhalation of respiratory droplets from infected animals or humans with pneumonic plague

What are the symptoms of plague?

1. Bubonic plague: Initial fever, headaches, body aches followed by painful lymph nodes, typically in the groin, armpit, or neck region.

2. Septicaemic plague: This occurs when the plague bacteria (Y. pestis) invade the bloodstream. Symptoms can include fever, chills, extreme weakness, abdominal pain, shock, and possibly bleeding into the skin and other organs.

3. Pneumonic plague: The least common but most dangerous and fatal form of the disease. Symptoms include severe pneumonia, fever, difficulty breathing, and blood in sputum.

What are the risk factors?

Risk factors include:

• Persons living in areas with poor rodent sanitation practices

• Hunters, trappers, trekkers, veterinary staff, and farmers operating in areas with known incidence of plague

• Travellers exposed to rodents in plague-affected countries

How is plague treated?

Antibiotics are effective against plague if patients are diagnosed and treated early. Supportive care and symptomatic treatment are given to alleviate symptoms and reduce complications.

How to prevent plague?

• Take precautions against flea bites and implement rodent control measures.

• If exposed to plague, seek medical attention to discuss post-exposure prophylaxis, or medicines that can prevent disease after exposure.

There is currently no approved vaccine against plague in Singapore.