Coccidia are microscopic parasites that infect a dog after the ingestion of a cyst found in contaminated environments. They live in the lining cells of the intestinal tract and have the ability to reproduce quickly. The rapid coccidia reproduction causes intestinal disruption and can cause Coccidiosis, an intestinal tract infection. Diarrhea is the most common sign of coccidia infection. Severe infections can be fatal in puppies if they do not receive prompt treatment. Healthy dogs may not show any symptoms, even though the coccidia is still living within the cells of their intestinal lining. Coccidia oocysts (immature coccidia) can shed intermittently in the dog feces, which can re-infect them or infect other dogs. Stress-related events can be a factor in a dog causing a digestive upset, allowing the coccidia an opportunity to escape from the intestinal lining into the gut and reproduce.
What is coccidia?
Coccidia are tiny, single-celled organisms, classified as protozoa. It is species-specific and is sub-classified into several genera or groups. There are at least four different coccidia genera that infect dogs, with Isospora canis generally the cause of dog infections.. Coccidia is spread thru infected feces or ingestion of infected tissues. An ingested coccidia oocyst can complete its life cycle in the gut, reproduce, and shed in dog feces. Sporulation or maturity of the oocyst can occur in 7-12 hours infecting the soil or vegetation. Coccidia is quite hardy and can survive up to one year in a moist, protected environment, if not exposed to extreme heat or freezing.
How would a dog be exposed to coccidia?
Coccidian parasites are found in infected feces, wildlife droppings, or contaminated soil. A dog can ingest coccidian parasites by eating infected soil or vegetation. Coccidia can also adhere to their fur or paw after contact with contaminants, increasing the risk of the pet swallowing cysts while licking or cleaning their fur or paw. Another source of coccidia infection is if the dog ingests infected tissue after eating an infected rabbit or rodent.
So how would a newborn puppy be at risk of infection by coccidia?
Puppies are born with a relatively sterile gut and receive their earliest gut microbiome from the mother while nursing. Their environmental exposure has been in the kennel or whelping area with a healthy mother and their littermates. Mother is caring for them and providing nourishment during nursing. Lactation or the production of milk for nursing is a stress factor for mothers. If she has had a previous coccidia infection, she has coccidia living in the cells of her intestinal lining. The stress-related disruption of lactating to the mother's digestive system can cause the coccidia to now escape into the gut, reproduce, and shed oocysts in her feces. The new puppies that are in the kennel with her can be infected if they swallow cysts while licking their fur or paws after walking or rolling in her infected feces.
What are the symptoms of coccidiosis?
Since a coccidia infection disrupts gut function, symptoms are generally gastrointestinal:
- Diarrhea: Can be severe, is often watery and streaked with blood or mucus
- Abdominal distress: Occasional vomiting or stomach cramps
- Weight Loss
- Anorexia: Poor appetite
Not all dogs will become ill after becoming infected with coccidia. An adult dog with a healthy immune system is often able to suppress the parasite and be asymptomatic, while others may appear droopy and "not themselves" and have watery diarrhea. If the dog has no other challenging health conditions, a bland diet and digestive aids or probiotics may help them recover from symptoms and develop immunity after two to three weeks. However, the coccidia is still in their gut and can be shed during this period. Young puppies are especially susceptible to coccidia infection symptoms. Their underdeveloped immune systems and little body reserves cannot protect them from fluid loss during diarrhea, which can lead to life-threatening dehydration. Chronically ill dogs with weakened immune systems also may suffer more severe symptoms.
How do I know if my dog has a coccidia infection?
Your veterinarian may perform a fecal flotation test. The test requires a fecal sample from your dog that is mixed with a special flotation fluid, allowing the coccidia to float to the top of the mixture. A specimen is taken and viewed under a microscope by your veterinarian. A positive test results from the spotting of coccidia by your vet. A false-negative test is possible since the oocysts are shed intermittently and may not be present in the stool sample you collected. After a negative test, your veterinarian may want to do an additional fecal flotation test from a new stool sample, or they may choose to treat your pet for a coccidia infection based on clinical signs presented.
What treatments are available for a coccidia infection?
Your veterinarian may prescribe, Sulfadimethoxine, also known by brand name Albon®, which is effective against bacterial enteritis associated with coccidia infection. Treatment typically lasts 5-25 days. Sulfadimethoxine does not kill the organisms directly but works by preventing the reproduction of the parasites. In severe infections treatment may need to be repeated. As with many anti-bacterial medications, Albon may have some resistance in repetitive treatment over a-period -of-time. An alternative sulfa-drug that has been used with efficacy is Sulfa-Trimeth or Sulfamethoxazole and Trimethoprim Oral Suspension. An "off-label" treatment recommended by some experts is a drug called Ponazuril or Marquis®. Some vets may not have heard about its efficacy in treatment or may be hesitant to prescribe so please visit with your veterinarian about this treatment. Marquis® has a good safety margin in puppies over six weeks of age. If under six weeks of age, there is a possibility of a condition called dry eye that may lead to eye ulcers in flat-nosed breeds. If a puppy or kitten is suffering from severe dehydration, hospitalization and fluid therapy may also be required.
If you are concerned that previous exposure to coccidia by your pregnant dog increases the possibility of coccidia infection to the new litter, visit with your veterinarian about any pre-whelping treatments available to the mother. This precaution is important since many products are not safe in pregnant moms. An example is the use of sulfa-drugs which may increase the incidence of cleft palates in dogs if used between the 25th and 30th days of gestation.
What preventive steps can I take to protect my dog against coccidia exposure or reinfection?
Good hygiene in your dog's environment is a top priority! Dog feces should be removed and disposed of as soon as possible from areas they frequent. Washing your pet's anal area and hind legs with soapy water is beneficial in removing any cysts that have adhered there, reducing the incidence of swallowing a cyst while licking their fur or paw. It is also important to wash your pet's bedding, food, and water bowls. Clean and use a disinfectant on any surface your pet contacts, to help eliminate any cysts. If possible, keep pets from hunting rodents or rabbits.Related article: Comparing Disinfectants that Kill Pathogens Important in Pet Facilities >>
Coccidian infections for pets are common and multiple options for treatment are available. It is wise to remember that diarrhea is only a symptom and not a diagnosis, so if your pet is sick, always contact your veterinarian.