# Coccidia in Cats: Poop Signs and How to Clean Coccidia in cats poop usually shows up as diarrhea, sometimes with mucus or blood, and the oocysts themselves are too small to see without a microscope. If your cat has soft or watery stools, a fecal test at your vet can confirm whether coccidia are the cause. This article is educational and is not a substitute for veterinary diagnosis or treatment. ## Quick Answer - Coccidia oocysts are microscopic, so you cannot reliably identify them in the litter box by eye. A vet uses fecal flotation to find them [1]. - The most common coccidia in cats are Isospora (Cystoisospora) felis and Isospora rivolta, and they are host-specific to cats [2]. - Diarrhea is the main sign, and it can be watery or contain blood in some infections [1][3]. - Most cats get infected young, and illness is most likely in kittens around weaning (4 to 12 weeks old) [2]. - Cleaning must remove feces promptly and use a disinfectant proven to kill oocysts, because routine household cleaners often do not. ## What Is Coccidia in Cats? Coccidia are single-celled parasites that live inside the cells lining the intestine [1]. They belong to a group called protozoa, and the types that infect cats are different from the types that infect dogs or birds [2]. Cats can carry several genera, including Hammondia, Isospora, Besnoitia, Toxoplasma, and Sarcocystis [2]. The two that cause the most common intestinal infections in cats are Isospora felis and Isospora rivolta [2]. These parasites are host-specific, which means the coccidia that infect your cat generally do not infect you or your dog [2]. That said, some related parasites in this family, such as Toxoplasma, do have public health importance, so good litter box hygiene matters for other reasons too. When a cat swallows an infected oocyst, the parasite invades the intestinal lining and multiplies. The cat then sheds new oocysts in the stool. Shedding can be heavy, and heavy shedding is linked to clinical signs, especially in kittens [2]. ## What Does Coccidia Poop Look Like in Cats? This is the question most owners ask first. The honest answer is that the poop changes are easier to see than the parasite. **The stool itself** often becomes soft, pasty, or watery. In one study of young cats with diarrhea, watery or hemorrhagic diarrhea was seen in some cats infected with C. felis and C. rivolta [3]. You may notice mucus, a change in color, or streaks of fresh blood. Some cats have only mild soft stool. Others have frequent, urgent diarrhea. **The oocysts** are another matter. They are microscopic, so they are not visible as worms, rice grains, or moving specks. What owners sometimes see in the litter box and mistake for coccidia are usually other things, such as tapeworm segments, mucus, or undigested material. If you are seeing something white and rice-like around the anus or in the stool, that is more consistent with tapeworms, and your vet should check a stool sample. **What vets see** under the microscope is different. Isospora oocysts are identified by their size and shape, which is how I felis and I rivolta are told apart [2]. A sporulated Isospora oocyst contains two sporocysts [1]. None of this is visible to the naked eye. If your cat is straining and passing only mucus, that can have several causes, including intestinal parasites, and it is worth reading about [Cat Straining to Poop but Only Passing Mucus: Causes and Care](/knowledge/veterinary-medicine/digestive-and-urinary-care/cat-straining-poop-mucus). Straining to defecate can also be confused with urinary problems, which are a different emergency. If you are unsure which end is involved, these guides can help you sort out the signs: [Signs Of A Urinary Tract Infection In My Cat](/knowledge/veterinary-medicine/clinical-methods/signs-of-a-urinary-tract-infection-in-my-cat) and [Signs Of Female Cat Uti](/knowledge/veterinary-medicine/clinical-methods/signs-of-female-cat-uti). ## Signs Owners Notice Diarrhea is the main clinical sign of coccidiosis [1]. Beyond that, you might see: - Soft, pasty, or watery stool that lasts more than a day or two - Mucus in the stool - Fresh blood or a dark, tarry appearance - Straining or frequent trips to the litter box - A messy rear end, since loose stool clings to fur - Reduced appetite or weight loss in kittens - Low energy in young or debilitated cats Kittens are the group most likely to get sick. Clinical signs tend to appear in kittens 4 to 12 weeks old, often around the stress of weaning [2]. Adult cats with a healthy immune system usually handle infection well, and immunity after exposure is good, especially in cats [2]. Adults that are debilitated or immunocompromised can occasionally develop illness [2]. ## Causes and Risk Factors Infection happens when a cat swallows an oocyst from the environment. That can mean contaminated soil, contaminated food or water, or oocysts tracked from a litter box on paws, shoes, or cleaning tools. Risk factors include: - **Age.** Kittens are the most affected group [2]. - **Stress.** Weaning is a common trigger for illness in kittens [2]. - **Crowding.** Catteries, shelters, and multi-cat homes make fecal contamination more likely. - **Outdoor access or free-roaming.** Coccidia were found in 11.5% of free-roaming cats tested in one New York City study [4]. - **Other intestinal parasites.** Co-infections with roundworms, hookworms, and Giardia are common in cats with diarrhea [3]. - **Recent import or rescue from another region.** Cats adopted from abroad can arrive with multiple parasites at once, including Cystoisospora [5]. Coccidia are common. In a study of young cats with diarrhea, 33.9% tested positive for coccidia, with C. felis the most frequent [3]. In another study of urban cats, coccidia were found in 11.5% of free-roaming cats sampled [4]. These numbers show how easily cats encounter these parasites. ## How Coccidia Is Diagnosed Your vet will start with the history: how long the diarrhea has lasted, what it looks like, your cat's age, and any recent changes. Then comes the stool sample. Fecal flotation is the standard test. The sample is mixed with a salt or sugar solution so that parasite eggs and oocysts float to the surface, where they can be collected and examined under a microscope [1]. Because oocysts can be shed in waves, a single sample can miss the infection. Your vet may ask for a sample collected over two or three days, or they may run a repeat test. Other methods include direct intestinal smears and a McMaster counting chamber, which can estimate how heavy the shedding is [1]. In some cases, your vet may recommend additional testing for other parasites such as Giardia, roundworms, or hookworms, since co-infections are common in cats with diarrhea [3]. ## Treatment Options Treatment for coccidiosis is prescription antiprotozoal medication. Your veterinarian calculates the dose from your cat's weight and overall health, and the exact drug and duration depend on the case. Antiprotozoal treatment can shorten the illness, reduce oocyst shedding, ease clinical signs, and lower the risk of secondary infections and death [1]. A few practical points: - **Do not use over-the-counter dewormers.** Dewormers target worms, not coccidia. Giving the wrong product delays real treatment. - **Finish the full course.** Stopping early can lead to relapse and more shedding into the environment. - **Treat other parasites too.** If your cat also has roundworms, hookworms, or Giardia, those need their own treatment [3]. - **Supportive care matters.** Kittens with diarrhea can dehydrate quickly. Your vet may recommend fluids, a bland diet, or a prescription gastrointestinal diet during recovery. If your cat was recently imported or adopted from another region, tell your vet. Cats from other countries can carry multiple parasites at once, and the treatment plan may need to cover more than coccidia [5]. ## Recovery, Outlook, and Long-Term Management Most cats recover well with treatment, especially when the infection is caught early. Kittens may need a few days of supportive care before their stool firms up. Immunity after natural exposure is good in cats, so repeat illness is uncommon in healthy adults [2]. Long-term management focuses on three things: 1. **Repeat fecal testing.** Your vet may want to recheck the stool after treatment to confirm the shedding has stopped. 2. **Litter box hygiene.** Remove feces daily and clean the box regularly. This limits the number of oocysts your cat and other cats encounter. 3. **Managing other cats.** If you have multiple cats, watch for diarrhea in the others and have them tested if signs appear. Coccidia oocysts are hardy in the environment. They have a thick outer wall that helps them survive drying and many common disinfectants. That is why cleaning needs to be deliberate, not just a quick wipe. ## How to Disinfect Coccidia in Cats: A Step-by-Step Routine This is the part most owners get wrong. Standard cleaning with soap and water removes debris, but it does not reliably kill oocysts. You need mechanical removal plus a disinfectant that is labeled to kill coccidia, or heat. ### Step 1: Remove feces immediately Scoop solid waste from the litter box as soon as you notice it. Oocysts are shed in feces, so the faster you remove them, the less contamination spreads [1]. Wear disposable gloves, and wash your hands afterward. ### Step 2: Empty and wash the box Empty the entire litter box. Discard used litter in a sealed bag. Wash the box with hot water and dish soap to remove organic material. Disinfectants work poorly when feces or litter dust is still present. ### Step 3: Disinfect with the right product Use a disinfectant labeled for coccidia, or a diluted bleach solution made fresh that day. Follow the label contact time exactly. Many products need the surface to stay wet for several minutes. Rinse thoroughly and let the box dry completely before adding new litter. ### Step 4: Use heat where you can Steam cleaning or washing items in very hot water is one of the most reliable ways to destroy oocysts. If a litter box, scoop, or food bowl can go in a dishwasher on a hot cycle, that helps. Replace porous items that are hard to clean. ### Step 5: Handle litter and waste carefully - Use a dedicated scoop and store it away from food areas. - Bag waste before putting it in the trash. - Do not compost cat litter. - Keep pregnant women, young children, and immunocompromised people away from litter box duties when possible, since cat feces can carry other parasites of human health concern. ### Step 6: Clean the surrounding area Oocysts can be tracked out of the box on paws. Wash floors, baseboards, and any washable surfaces near the litter box. Vacuum carpets and dispose of the vacuum bag or empty the canister outside. Wash bedding, blankets, and cat beds in hot water. ### Step 7: Repeat and monitor Clean the box daily and do a full disinfection at least weekly while your cat is being treated. Continue until your vet confirms the infection has cleared. If you have multiple cats, clean all boxes, not just the one used by the affected cat. ### Quick reference table | Item | What to do | Why it matters | |---|---|---| | Litter box | Empty, wash with soap and hot water, disinfect, rinse, dry | Removes and kills oocysts | | Litter scoop | Wash and disinfect or replace | Easily overlooked source of contamination | | Food and water bowls | Wash daily in hot water | Prevents fecal-oral spread | | Bedding and blankets | Wash in hot water | Oocysts can cling to fabric | | Floors and baseboards | Wash with disinfectant | Paws track oocysts out of the box | | Carpets | Vacuum, dispose of contents outside | Reduces environmental load | | Hands | Wash after every cleaning session | Protects you and your family | ## Prevention Prevention comes down to reducing exposure and keeping cats healthy. - **Clean the litter box daily.** Remove feces before oocysts have time to spread. - **Disinfect regularly.** Use a product labeled for coccidia and follow the contact time. - **Wash your hands.** Do this after scooping, gardening, or handling any cat with diarrhea. - **Keep kittens away from contaminated areas.** Young kittens are the most vulnerable group [2]. - **Test new cats.** Any new cat or kitten should have a fecal test before joining a multi-cat home. - **Screen imported or rescue cats.** Cats from other regions may carry several parasites at once [5]. - **Control other parasites.** Roundworms, hookworms, and Giardia often appear alongside coccidia in cats with diarrhea [3]. - **Reduce stress during weaning.** Since illness in kittens often appears around weaning stress, keep the transition calm and gradual [2]. ## Limitations and When to Contact a Veterinarian No article can tell you what is happening in your cat's gut. Individual cases need a veterinarian who can examine your cat and test the stool. **Contact your vet the same day if:** - Your cat has had diarrhea for more than 24 hours - You see blood or mucus in the stool - Your kitten has any diarrhea at all, since kittens dehydrate fast - Your cat is eating less or acting tired - Your cat is straining and passing only small amounts **Go to an emergency clinic now if:** - Your cat is vomiting repeatedly and cannot keep water down - Your cat is weak, wobbly, or unresponsive - You see a large amount of blood - Your cat is straining to urinate or has not urinated, which can be a urinary blockage and is life threatening **Schedule a routine visit if:** - Your cat has intermittent soft stool - You want a fecal test before adding a new cat to the home - Your cat has been treated for coccidia and you need a recheck ## Frequently Asked Questions ### Can I see coccidia in my cat's poop? No, you cannot see coccidia oocysts with the naked eye. They are microscopic and require fecal flotation to identify [1]. What you see in the litter box is the effect of the infection, such as diarrhea, mucus, or blood, not the parasite itself. ### Is coccidia contagious to other cats in my home? Yes, coccidia spread between cats through contaminated feces and environment. The species that infect cats are host-specific, so they do not infect dogs or people [2]. If one cat in your home has coccidia, clean all litter boxes and watch the other cats for diarrhea. ### How long does coccidia last in a cat? With treatment, most cats improve within days, though the exact timeline depends on the cat's age and health. Antiprotozoal treatment shortens the illness and reduces oocyst shedding [1]. Your vet will decide when to recheck the stool to confirm the infection has cleared. ### Do I need to throw away my litter box? Not always, but you must clean it thoroughly. Oocysts have a tough outer wall that resists many cleaners, so wash the box with soap and hot water, then disinfect with a product labeled for coccidia and let it dry. Replace the box if it is scratched or porous and hard to disinfect. ### Can my cat get coccidia again after treatment? Reinfection is possible, but immunity after exposure is good in cats, so repeat illness is uncommon in healthy adults [2]. The bigger risk is ongoing exposure from a contaminated environment. Daily litter box cleaning and regular disinfection lower that risk. ## Related Articles - [Signs Of A Urinary Tract Infection In My Cat](/knowledge/veterinary-medicine/clinical-methods/signs-of-a-urinary-tract-infection-in-my-cat) - [What Are The Signs That My Cat Has A Urinary Tract Infection](/knowledge/veterinary-medicine/clinical-methods/what-are-the-signs-that-my-cat-has-a-urinary-tract-infection) - [Signs Of Urinary Tract Infection In Cats Female](/knowledge/veterinary-medicine/clinical-methods/signs-of-urinary-tract-infection-in-cats-female) - [Signs Of Female Cat Uti](/knowledge/veterinary-medicine/clinical-methods/signs-of-female-cat-uti) - [Cat Straining to Poop but Only Passing Mucus: Causes and Care](/knowledge/veterinary-medicine/digestive-and-urinary-care/cat-straining-poop-mucus) - [Intestinal Parasites in Dogs and Cats: Signs and Prevention](/knowledge/veterinary-medicine/parasitic-diseases/intestinal-parasites-in-dogs-and-cats) - [Coccidia in Cats: Symptoms to Watch For](/knowledge/veterinary-medicine/parasitic-diseases/coccidia-cats-symptoms) - [Coccidia in Cats: Treatment and Medication Options](/knowledge/veterinary-medicine/pet-medication-guide/coccidia-cats-treatment-medication) - [How Long Does Coccidia Last in Cats?](/knowledge/veterinary-medicine/parasitic-diseases/how-long-does-coccidia-last-cats) - [Avian and Feline Parasites: Coccidiosis, Intestinal Parasites of Dogs, and Toxoplasmosis](/knowledge/parasites/avian-parasites/avian-feline-parasites-coccidiosis-intestinal-parasites-toxoplasmosis) ## References 1. [Overview of Coccidiosis in Animals - Digestive System](https://www.merckvetmanual.com/digestive-system/coccidiosis/overview-of-coccidiosis-in-animals). Merck Veterinary Manual. 2. [Coccidiosis of Cats and Dogs - Digestive System](https://www.merckvetmanual.com/digestive-system/coccidiosis/coccidiosis-of-cats-and-dogs). Merck Veterinary Manual. 3. [Occurrence of Cystoisospora spp. and other intestinal parasites in dogs and cats with diarrhea](https://pubmed.ncbi.nlm.nih.gov/40690864/). Veterinary parasitology, 2025. 4. [Zoonotic endoparasites and Toxoplasma gondii seropositivity in free-roaming cats (Felis catus) from New York City boroughs](https://pubmed.ncbi.nlm.nih.gov/42418442/). PloS one, 2026. 5. [Clinical co-parasitic infections in a cat imported from Thailand](https://pubmed.ncbi.nlm.nih.gov/41847483/). The Canadian veterinary journal = La revue veterinaire canadienne, 2026. ## Further Reading - [Merck Veterinary Manual: Cat Owners](https://www.merckvetmanual.com/cat-owners) - [Cornell Feline Health Center: Health Information](https://www.vet.cornell.edu/departments-centers-and-institutes/cornell-feline-health-center/health-information) - [American Veterinary Medical Association: Pet Care](https://www.avma.org/resources-tools/pet-owners/petcare)