The Hidden Danger. Why Cat Saliva Can Be Toxic to Small Animals


Cat saliva contains bacteria that can be toxic to small animals like birds, reptiles, and rodents. When a cat bites or scratches these types of animals, its saliva can enter the wound and cause illness or even death. This toxicity is due to a bacterium called Pasteurella, which is commonly found in the mouths of healthy cats. While Pasteurella does not make cats sick, it can be extremely dangerous if transmitted to susceptible animals through a bite or scratch.

This article provides an overview of why cat saliva is toxic to small animals, which types of animals are most at risk, how the toxin can be transmitted, symptoms it causes, how to prevent transmission, first aid if an animal is bitten/scratched, treatment options, prognosis for recovery, and key conclusions on this important topic for pet owners and wildlife rehabilitators.

Why Cat Saliva is Toxic

Cat saliva contains bacteria that are toxic to small animals. One of the main bacteria is Pasteurella multocida, which is found in over 90% of healthy cats’ mouths (Bird Conservancy of the Rockies). This bacteria can cause severe infections if transmitted through a bite or scratch from a cat. According to the Bird Conservancy of the Rockies, “The bacteria in cat saliva are toxic to birds, so even if a cat does not immediately kill a bird, its bite often leads to infection and death.” Even a small puncture from a cat’s tooth can allow the bacteria to enter the body and bloodstream of a small animal, leading to potentially fatal septicemia, respiratory infections, or abscesses if left untreated.

Small Animals at Risk

Cat saliva contains bacteria that can be deadly to small animals like birds, reptiles, and rodents. Even a small scratch or bite from a cat exposes these animals to the bacteria and can lead to infection. According to one source, “Cats carry a bacteria in their mouth called Pasteurella. And it can make your rats and other rodents extremely sick” (Source). Birds and reptiles are also very susceptible.

Specifically, the following small animals are at high risk of illness or death when exposed to cat saliva:

  • Birds – Songbirds, parrots, finches etc. Even a minor scratch can expose them to deadly infection.
  • Reptiles – Small lizards, geckos, snakes and turtles are very vulnerable to the bacteria in cat saliva.
  • Rodents – Rats, mice, hamsters, gerbils, guinea pigs can develop serious infections from cat scratches and bites. According to one wildlife rescue organization, “Cat saliva is deadly, so in spite of the antibiotics, many of these animals will die.” (Source)

In summary, birds, reptiles and rodents are very susceptible to illness and death when exposed to cat saliva through bites, scratches, or other contact. Owners of these small animals need to be vigilant about keeping cats away from them.

Modes of Transmission

Cat saliva can transmit diseases and infections to other animals through several modes of transmission. The main ways cat saliva infects other animals are through bites, scratches, and grooming.

Bites from cats can introduce pathogens directly into the bloodstream or tissues of another animal. Deep puncture wounds are especially dangerous. Studies show bite wounds have a high risk of bacterial infection, with pasteurella and other bacteria commonly isolated from infected cat bites.

Even small scratches from cats can expose tissues to infectious saliva. Scratches often go unnoticed, allowing pathogens time to enter the body before any first aid is applied. The bacteria Bartonella henselae, which causes Cat Scratch Disease in humans, is one example of a potentially serious scratch-transmitted infection.

Grooming between cats, or between cats and other animals like dogs, facilitates saliva transfer. Diseases like feline immunodeficiency virus can spread through grooming behaviors that expose mucous membranes to infected saliva.


Cat saliva can contain numerous bacteria that are toxic to small animals, including Pasteurella multocida, Bartonella henselae (cat scratch disease), and Capnocytophaga canimorsus. When transmitted via a bite or scratch, these bacteria can cause serious and even fatal infections in birds, rodents, rabbits, and other small pets.

Common symptoms include:

  • Respiratory infections: Labored breathing, wheezing, sneezing, nasal discharge. Respiratory infections are extremely common, as cat saliva is easily inhaled into the lungs during an attack.
  • Skin infections: Redness, swelling, pus, abscesses around bite/scratch wounds. Pasteurella and other bacteria quickly spread under the skin.
  • Sepsis: Lethargy, loss of appetite, swelling, fever. Bacteria entering the bloodstream can rapidly lead to sepsis and shock.

According to veterinarians, small animals that survive the initial cat attack often develop serious secondary infections within 24-48 hours (Source). Swift medical attention is critical.


The best way to prevent transmission of diseases from cats to small pets is to keep cats indoors and not allow them to interact with small animals like rodents, birds, and reptiles. Cats are natural hunters and can easily infect and kill small pets with their saliva and scratches. According to the Cornell Feline Health Center, “Proper hygiene, including washing hands before meals, cleaning soil from vegetables, and reducing exposure to cat feces can prevent infection.”

If you have both cats and small pets, it’s important to keep them separated at all times. Your cats should be indoor-only, or kept in an outdoor enclosure where they can’t access areas that small pets inhabit. Small pets like hamsters, gerbils, and birds should be kept in cages that cats can’t access. Don’t allow cats into rooms where small pets are free-roaming.

Supervise all interactions between cats and small animals closely to prevent hunting behaviors. Keep cats on leashes when outside so they don’t stray to areas small pets frequent. Disinfect any scratches or bites from cats immediately to prevent transmission of bacteria. With proper precautions, cat owners can safely have both cats and small pets in their home.

First Aid

If you are bitten or scratched by a cat, it is crucial to promptly wash the wound with soap and water to help flush out bacteria. According to the veterinarians at VCA Animal Hospitals, “You may clean the wound with a mild soap solution or a mild salt solution.”1

After thoroughly cleansing the wound, apply an antibiotic ointment containing ingredients like polymyxin B, bacitracin, and neomycin, as recommended by the experts at Cleveland Clinic.2 These antibiotics help prevent infection from the bacteria commonly found in cat saliva.

It is also advisable to contact your physician about the potential need for antibiotics, a tetanus shot, or rabies vaccine. Cat bites and scratches can introduce dangerous bacteria deep into the skin and tissue. Seeking prompt medical attention can help prevent serious infection. As Stanford Children’s Health notes, “Early treatment is important to prevent the infection from getting worse.”3


Treatment for cat saliva infection depends on the specific condition, but often involves antibiotics and supportive care under veterinary supervision. According to Hopkins Medicine, antibiotics can be prescribed to treat the bacterial infection caused by cat scratches or bites. The specific antibiotic depends on the type of bacteria involved. In uncomplicated cases, antibiotics may not be necessary as the infection often resolves on its own.

According to VCA Animal Hospitals, cats with calicivirus infections can often be treated symptomatically at home under veterinary guidance. This may include medications to treat eye infections caused by the virus. More severe infections may require supportive care such as IV fluids and nutrition.

As noted by the University of Rochester Medical Center, the specific antibiotic and length of treatment depends on the type of bacteria causing cat scratch disease. Supportive care may also be needed to manage any symptoms until the infection resolves.


The prognosis for small animals affected by cat saliva toxicity depends on several factors, including the time to treatment, the species affected, and the virulence of the bacteria present in the cat’s saliva. In general, the earlier treatment is started after exposure, the better the prognosis.

Small mammals and birds tend to be more severely affected than dogs, likely due to their smaller size. Guinea pigs, hamsters, gerbils, and rabbits often develop dangerous infections and sepsis quickly after being bitten or scratched by a cat. With aggressive treatment, their prognosis is fair to good if brought to a veterinarian promptly.

The type of bacteria present in the cat’s saliva greatly impacts the severity of the illness. Pasteurella and Capnocytophaga species tend to cause more systemic illness, whereas Streptococcus and Staphylococcus cause more localized infections. However, Pasteurella multocida is a common commensal bacterium in cats that can lead to rapidly progressive infections in rabbits and rodents.

With timely veterinary care, most pets can recover fully from cat scratches and bites. However, neglect or delay in treatment can lead to septicemia, organ failure, and death in severe cases. Pet owners should monitor all small animals carefully after encounters with cats and seek treatment at the first sign of lethargy, swelling, fever, or other symptoms.


In summary, cat saliva can be toxic to small animals like rodents, rabbits, and birds due to bacteria present in a cat’s mouth. Even a small scratch or bite from a cat can lead to infection, illness, and potentially death in these small pets. Responsible cat ownership is crucial to protect our furry friends as well as small animals in the home.

It’s important to keep cats separated from small pets, supervise all interactions, and trim nails regularly. Seek immediate veterinary care if a cat injures a small pet. With proper precautions, we can keep all of our companion animals safe and healthy.

Leave a Comment

Your email address will not be published. Required fields are marked *

Scroll to Top