Is Your Water Safe After Kitty Kisses? The Truth About Drinking From Contaminated Glasses


Many pet owners allow their cats to drink from their water glasses or lick their dinner plates. This friendly gesture may seem harmless, but is it safe to consume anything a cat’s mouth has touched? This article will examine the potential risks of drinking water after a cat has licked it. We’ll look at bacteria, parasites, and other contaminants cats may transfer, as well as precautions owners can take.

Risks of Bacteria

There are several types of bacteria commonly found in cat saliva that could contaminate water and pose a risk to humans if ingested. Two of the main bacteria of concern are Pasteurella and Capnocytophaga.

Pasteurella multocida bacteria live naturally in many cats’ mouths without causing issues for the cats. However, according to an article on CBC News, Doctor’s warning: a cat’s bacteria is worse than its bite, Pasteurella can cause wound infections, abscesses, and sepsis in humans if transmitted via a cat bite or scratch.

Capnocytophaga canimorsus is another bacteria commonly found in cat saliva, as noted in this CDC article: Capnocytophaga. While not making cats sick, if transmitted to humans through a bite, scratch, or contact with saliva, it can cause rare but serious infections including septicemia, endocarditis, and meningitis.

So while low levels of bacteria from cat saliva in water may not cause issues for most healthy people, those with weakened immune systems could face risks of infection if they ingest the contaminated water. Precautions should be taken such as not sharing water bowls with pets.


Toxoplasmosis is an infection caused by the parasite Toxoplasma gondii, which cats can carry. Cats get infected by eating infected rodents, birds or other small animals, or anything contaminated with feces from another infected cat according to the CDC. The most common symptoms in cats include fever, loss of appetite, and lethargy, though symptoms depend on whether the infection is acute or chronic per Cornell University.

While humans can catch toxoplasmosis from cats, it’s not transmitted through cat saliva. Cat owners can only get infected through exposure to infected cat feces, either when cleaning the litter box or ingesting contaminated soil or water. As long as proper hygiene precautions are taken, drinking water licked by a cat does not pose a toxoplasmosis risk according to PetsBest.


Rabies is a viral disease that affects the central nervous system and is almost always fatal once symptoms appear. It is primarily transmitted through the bite and saliva of an infected animal. According to the CDC, rabies virus is transmitted when infected saliva comes into direct contact with human mucosa or fresh skin wounds. This means rabies can potentially be transmitted if a human is bitten by a rabid cat or if a rabid cat’s saliva comes into contact with open wounds or mucous membranes like the eyes, nose, or mouth.

However, according to WebMD and VCA Animal Hospitals, rabies cannot be transmitted simply through a rabid cat licking or drooling on intact human skin. The rabies virus cannot penetrate healthy unbroken human skin. For rabies transmission to occur from a rabid cat, its saliva would need direct contact with human mucous membranes or fresh open wounds that can allow the virus entry into the body. Overall the chances of rabies transmission from a rabid cat licking intact human skin is extremely low.



Many people are allergic to proteins found in cat saliva, dander (dead skin cells), and urine. The most common allergen is a protein called Fel d 1 found in cat saliva. When a cat grooms itself by licking its fur, the saliva dries and flakes off into tiny particles called dander. These particles containing Fel d 1 protein get released into the air where they can be inhaled (Source 1).

Other proteins that can trigger allergic reactions include Fel d 2, Fel d 3, Fel d 4, Fel d 5, Fel d 6, Fel d 7, and Fel d 8. These are present in cat skin, serum, and urine. People who are allergic to cats are often reacting to multiple cat allergen proteins, not just Fel d 1 (Source 2).

When people inhale the cat allergen proteins, it triggers an IgE antibody response. The immune system sees the proteins as foreign invaders and releases histamine to attack them. This causes allergy symptoms like sneezing, runny nose, watery eyes, and itching.


One parasite that can be transmitted through a cat’s saliva is Toxoplasma gondii, the parasite that causes toxoplasmosis. This microscopic parasite infects rodents but needs a cat’s body in order to sexually reproduce and complete its life cycle. An infected cat sheds Toxoplasma in its feces, which is how other cats get infected by ingesting contaminated soil, water or infected prey. The parasite can also be shed in small amounts in an infected cat’s saliva. If a human ingests the parasite by accidentally consuming anything contaminated with infected cat feces or saliva, they can develop toxoplasmosis.

While rare, toxoplasmosis infection can cause flu-like symptoms, swollen lymph nodes, muscle aches and eye infections in humans. It can also lead to more serious complications if a woman is infected while pregnant or if the immune system is compromised. However, a healthy immune system can usually prevent illness from a one-time exposure. Overall, the risk of toxoplasmosis from cat saliva contact is quite low, especially if proper precautions are taken.

Immune Systems

Healthy human immune systems are equipped to handle many of the bacteria and parasites found in cat saliva [1]. While a cat’s oral bacteria can potentially cause illness in immunocompromised people, individuals with properly functioning immune systems are generally able to fight off infection and illness from cat saliva.

Research shows that having pets can actually strengthen the human immune system over time. Exposure to a pet’s dander and saliva introduces new antigens that help the immune system build defenses [2]. As a result, pet owners tend to have fewer allergies and get sick less often.

However, those with weakened immune systems like the elderly, pregnant women, and chemotherapy patients should exercise caution with cat saliva exposure. Their compromised immune function puts them at greater risk of contracting an infection or illness from cat saliva [3].

For most healthy individuals, the immune system provides robust protection against the bacteria and parasites in cat saliva. But at-risk groups should take precautions to avoid excessive exposure.

Cleaning Methods

If your cat has licked your water and you are concerned about drinking it, there are some cleaning methods you can try to make the water safe for human consumption again:

Boiling – Bringing water to a rolling boil for 1-3 minutes can kill most bacteria and parasites. Be sure to let the water cool before drinking.

Bleach – Adding a small amount of unscented bleach (about 1/4 teaspoon per quart of water) can kill many germs. Let the water sit for 30 minutes before drinking. Thoroughly rinse out the bleach taste.

Alcohol – Rubbing alcohol or vodka can be added to licked water (approximately 1 tablespoon per quart) to disinfect it. The alcohol evaporates quickly.

Filtration – Using a commercial water filter, like a Brita, can remove some bacteria and parasites. Be sure to sanitize the filter first.

UV Light – Portable UV water purifiers inactivate many microorganisms by disrupting their DNA. Use according to package instructions.

In a pinch, adding lemon juice can help inhibit bacterial growth for a short time. Remember to wash the container thoroughly after treating the water.


Immunocompromised individuals such as those undergoing cancer treatment, people with HIV/AIDS, transplant recipients, and the elderly should take extra precautions around cats to avoid illness (Caring for Pets During Cancer Treatment). They should avoid activities that may prompt cat bites, scratches, or exposure to saliva such as playing roughly, startling the cat, or allowing the cat to lick bare skin (Zoonotic Disease: What Can I Catch from My Cat?). It is also wise for immunocompromised individuals to avoid cleaning litter boxes to reduce exposure to toxoplasmosis.

In general, good hygiene around cats is recommended. Wash hands thoroughly with soap and water after petting cats or cleaning litter boxes. Avoid kissing cats or allowing them to lick your face. Clean any bites or scratches right away with soap and water. Keep cats indoors and take them to the vet regularly to reduce the risk of them contracting and spreading diseases.


In summary, the risks associated with drinking water after a cat has licked or drank from it are generally low for healthy adults. While bacteria like salmonella or parasites like Toxoplasma gondii can be present in cat saliva and feces, transmission to humans through shared drinking water is quite rare ( For people with weakened immune systems, pregnant women, and young children, it’s wise to take extra precautions such as washing the container thoroughly before reuse, using a separate water bowl for the cat, or avoiding sharing water altogether. But for most pet owners, the benefits of staying hydrated outweigh the small chance of getting sick. Monitoring your cat’s health and maintaining proper hygiene is reasonable, but there’s no need to panic if you’ve swallowed a few shared sips.

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