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Rat-Bite Fever

This fact sheet answers frequently asked questions about Rat-Bite Fever.

Rat-bite fever is a disease caused by bacteria carried by rats, mice, and other rodents. Though rare in the United States, the disease can be serious.

The basics

How does RBF spread?

People can get RBF after interacting with an infected rodent. This can involve a bite or scratch, but people who handle rats and are not bitten or scratched can also get RBF. RBF can also spread through contaminated food and drink. RBF cannot spread from one person to another.

Who is at risk?

Anyone who comes into contact with an infected rodent is at risk for developing RBF. People who live in rat-infested buildings, have pet rats at home, or work with rats in a laboratory or pet store may be at increased risk.


What are the symptoms?

Symptoms usually develop 3-10 days after exposure to an infected rat, but may take as long as 3 weeks. Symptoms may include fever, vomiting, headache, muscle pain, joint pain, and rash.

Infected people will often first experience a fever, followed by a rash on their hands and feet 2-4 days later. This rash looks like flat, reddened areas with small bumps. One or more joints may then become swollen, red, or painful.

If left untreated, the symptoms can worsen to include infections of the heart, brain, lungs, and other organs. Though rare, RBF can be fatal if left untreated.


How can I prevent RBF?

You can protect yourself from RBF by avoiding contact with rodents and the places where they have been present. This includes avoiding eating or drinking anything that may have been near rodents.

If you handle rodents, be sure to wear protective gloves, avoid touching your mouth with your hands, and wash your hands regularly.


What is the treatment?

Antibiotics are available to cure RBF.

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