What is rat-bite fever? How to treat rat-bite fever effectively

Learn about Rat-Bite Fever, a serious bacterial illness from rodents. Discover its causes, key symptoms, and crucial prevention tips to stay safe.

6 September, 2025

Rat-Bite Fever is a potentially fatal bacterial illness that many people are unaware of, even those with pet rodents. Understanding the hidden dangers and symptoms is your first line of defense. Don't risk overlooking this serious infection.

What are the main causes of Rat-Bite Fever?

  • The illness is primarily caused by two different bacteria, Streptobacillus moniliformis in North America and Spirillum minus in Asia.
  • Infection occurs through a bite or scratch from an infected rodent, including rats, mice, squirrels, and gerbils, even seemingly healthy pets.
  • You can also get sick by consuming food or water contaminated with the urine or droppings of an infected rodent.
Chart illustrating common rat-bite fever symptoms

Key symptoms of Rat-Bite Fever to watch for

  • Initial symptoms typically include fever, vomiting, headache, and muscle pain, which can appear anywhere from three days to three weeks after exposure.
  • A characteristic rash on the hands and feet, along with painful, swollen joints, often develops a few days after the fever begins.
  • Without prompt antibiotic treatment, serious complications like infections of the heart, brain, or lungs can occur, making early diagnosis vital.

How can you prevent Rat-Bite Fever effectively?

  • Avoid direct contact with wild rodents and ensure your home is rodent-proof by sealing any holes or cracks that could serve as entry points.
  • If you have pet rodents, handle them carefully and wash your hands thoroughly with soap after touching them or their cages. 
  • Immediately clean any rodent bite or scratch wound with soap and warm water, then apply an antiseptic and seek prompt medical attention.

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Image of the disease rat-bite fever

Medical team providing treatment for rat-bite fever
The spiral-shaped Spirillum minus bacteria
Microscopic view of Streptobacillus moniliformis
Infographic explaining what is rat-bite fever
Clinical signs associated with Sodoku disease
Understanding the cause of Haverhill fever

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Prompt medical care is critical for treating Rat-Bite Fever effectively. If you develop symptoms after rodent contact, inform your doctor immediately about the exposure. Early action is key to a full and swift recovery.

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