Do Rats Bite?

Rats are generally shy and avoid humans, but there are some situations where they are more likely to bite people or pets. Understanding these circumstances is crucial for preventing bites and reducing risk. The main scenarios include:

Defensive or Cornered Rats: Rats will bite if they feel threatened, trapped, or cornered. This can happen when someone tries to handle a live rat, inadvertently startles it, or when a pet provokes it. In such situations, bites are often defensive rather than predatory.
Rats Protecting Their Nest or Young: Female rats, especially those nursing pups, can become aggressive if they perceive a threat to their nest. Bites are more likely if humans or pets disturb nesting areas in attics, basements, or walls.
Scarcity of Food: Hungry rats, particularly in areas where food is scarce, may become bolder and more likely to approach humans or pets. While they usually prefer scavenging rather than attacking, a very hungry rat may bite if it mistakes fingers or toes for food.
Rabid or Sick Rats: Though rare, rats can carry diseases like rat-bite fever. A sick or rabid rat may display unusual aggression and bite without provocation.
Accidental Encounters: Rats in attics, basements, or hidden wall voids may bite if someone reaches into their hiding spots. Pets, especially cats and dogs that hunt or corner rats, are more likely to get bitten during such encounters.

To reduce the chances of a rat bite, you should avoid handling live rats, keep pets away from areas where rats are active, secure food sources and trash to prevent rats from frequenting your home, and seal entry points to prevent rats from nesting indoors.

Rat Bites

Rat bites are more than just painful scratches—they carry several health risks that make them a serious concern for both humans and pets. The risks stem from bacteria, viruses, and sometimes parasites that rats can carry:

Bacterial Infections

Rat bites often puncture the skin, creating an entry point for bacteria. The most common bacterial concerns include:

Rat-Bite Fever (RBF): Caused by Streptobacillus moniliformis (more common in the U.S.) or Spirillum minus (more common in Asia). Symptoms usually appear 3–10 days after the bite and include fever, rash, vomiting, and joint pain. Can become severe or even fatal if untreated.
Tetanus: Rats carry Clostridium tetani spores in their environment, and deep puncture wounds from bites can introduce them. Tetanus is preventable with vaccination but can be life-threatening if not treated promptly.
Other Secondary Bacterial Infections: Pseudomonas, Streptococcus, and Staphylococcus infections can occur in the wound, causing swelling, redness, pus, or systemic infection.

Viral Infections

While less common than bacterial infections, rats can carry viruses such as:

Hantaviruses: Rare from bites, more common from exposure to urine, droppings, or nesting materials.
Leptospirosis: Can enter through bite wounds if contaminated with rat urine.

Allergic Reactions

Some individuals may develop localized allergic reactions to rat saliva.
Symptoms can include swelling, redness, itching, and in rare cases, systemic reactions like hives.

Physical Injury

Deep puncture wounds can damage nerves, tendons, or muscles, particularly on hands or feet.
In pets, bites may cause lacerations, abscesses, or severe tissue damage.

Risk to Pets

Cats and dogs bitten by rats can develop abscesses, infections, or even contract rat-bite fever.

What Do Rat Bites Look Like?

Rat bites have some characteristic features, but they can vary depending on the size of the rat, the location of the bite, and how long it has been since the injury occurred:

Puncture Marks

Rat bites usually appear as two small puncture wounds close together.
This pattern comes from the rat’s incisors, which are sharp, chisel-like teeth that leave narrow, deep marks.
The punctures may be 1–3 mm in diameter depending on the rat’s size.

Irregular Tear or Scrape

Surrounding the punctures, the skin may be torn or scraped if the rat moved its head while biting.
The edges may look jagged rather than clean-cut.

Bleeding

Rat bites often bleed moderately, especially if the wound is on a hand, finger, or foot.
Deeper punctures may continue to ooze blood intermittently.

Redness and Swelling

The area around the bite may become red, swollen, and warm within hours.
Some swelling is normal; excessive swelling may indicate infection.

Pain and Tenderness

Rat bites can be surprisingly painful because the punctures are deep.
Pain may increase if the wound becomes infected.

Signs of Infection

Within 24–48 hours, infection may appear as:

Pus or yellow/green discharge
Increased redness spreading around the wound
Red streaks moving up the limb (sign of lymphangitis)
Fever or flu-like symptoms

Visual Comparison

Fresh bite: Two small punctures, minor bleeding, surrounding redness.
Infected bite: Swollen, red, possibly oozing pus, may be warm to the touch, sometimes accompanied by fever or malaise.

Rat bites often occur on hands, fingers, or feet, but pets may get bitten anywhere, especially the face or legs, depending on how they cornered the rat.

What To Do About Rat Bites

If you’re bitten by a rat, it’s important to treat the situation seriously. Even though rat bites may not always look severe, they can transmit dangerous bacteria and diseases such as rat-bite fever, leptospirosis, and, in rare cases, tetanus or sepsis. Here’s what to do if you get bitten by a rat:

Immediately Clean the Wound

Wash the bite thoroughly with warm water and antibacterial soap for at least 5 minutes.
Encourage mild bleeding by gently pressing around the wound if it’s not bleeding much—this helps flush out contaminants.
Rinse thoroughly to remove all debris and saliva.

Disinfect the Area

After cleaning, apply an antiseptic such as hydrogen peroxide, iodine, or rubbing alcohol to kill bacteria.
Cover the wound with a clean, sterile dressing or bandage to prevent infection.

Control Bleeding (if necessary)

If the wound continues to bleed, apply gentle pressure with a clean cloth or sterile gauze until it stops.
For deeper punctures or lacerations, medical attention is essential.

Seek Medical Attention Promptly

Even if the bite seems minor, see a healthcare provider within 24 hours. You may need:

Antibiotics to prevent infection (especially for rat-bite fever, which can be transmitted through bacteria like Streptobacillus moniliformis).
A tetanus booster if you haven’t had one in the past 5–10 years.
A rabies assessment—though rats rarely carry rabies, your doctor will evaluate the risk based on local wildlife activity and circumstances of the bite.

Watch for Symptoms of Infection or Illness

In the days following the bite, monitor for:

Redness, swelling, warmth, or pus at the wound site
Fever, rash, or joint pain
Chills, muscle aches, or vomiting

If any of these occur, seek emergency care immediately—these may indicate a spreading infection or rat-bite fever.

Report and Prevent Future Incidents

Report the incident to local health authorities if required, particularly if the bite occurred at work or in a public setting.
Identify and address the rat infestation source to prevent further exposure. Our professional pest control intervention may be necessary to eliminate nests and entry points safely.