Toxoplasmosis in Dogs

Toxoplasmosis is an infection caused by a single-celled organism, Toxoplasma gondii, capable of infecting both dog and owner alike. The infection is spread either through the feces of infected cats (as sporozoites) or undercooked meat (as tissue cysts). After consumption, the organisms invade the lining of the stomach and lower intestine, quickly spreading throughout the body. In young animals or those with compromised immune systems, this can be fatal if untreated. Older animals with good immune systems usually do not require treatment as they are able to contain the infection and often eliminate it completely. However, the infection can sometimes persist as asymptomatic “pockets” of organisms inside the animal, called bradyzoites.

• Vomiting
• Diarrhea
• Tremors
• Shortness of breath
• Fever
• Weight loss
• Refusal of food
• Inflammation of the eyes
• Lethargy/muscle weakness

Types

• Acute
• Chronic
• Fetal

If you notice your dog behaving strangely, running a fever or exhibiting tremors, schedule a veterinarian appointment immediately, especially if you suspect your dog has eaten roadkill or from the litterbox.

Acute Toxoplasmosis

Toxoplasmosis may be suspected if your pet has consumed raw or undercooked meat, cat feces, or come in contact with areas contaminated by the same. Gastrointestinal or neurologic symptoms should be reported to a veterinarian regardless, but especially in the case of toxoplasmosis infection, as time may be critical to save a young or vulnerable pet’s life.

The veterinarian can diagnose toxoplasmosis by a variety of lab tests, involving samples of the blood, feces or spinal fluid. The symptoms of toxoplasmosis alone are not enough for a firm diagnosis, and so these laboratory tests are essential.

Chronic Toxoplasmosis

Animals infected with toxoplasmosis as adults may sometimes retain pockets of the infection, which can remain viable for months or years. Usually, this does not cause any symptoms nor does it pose a threat to the animal’s health, but can be of concern if the animal is in contact with at-risk animals.

Fetal Toxoplasmosis

Females infected with toxoplasmosis carry a significant risk of transmitting the infection to their young while still in the womb. Young are often stillborn or die shortly after birth. In humans, toxoplasmosis in pregnant women can cause severe birth defects or miscarriage of the fetus.

Acute toxoplasmosis may be treated with sulfadiazine and pyrimethamine, which are helpful in suppressing active multiplication of the parasite. Clindamycin is also highly prescribed for dogs. These drugs will not usually completely clear the infection, so the animal’s own immune system should be supported to eliminate the rest. If brought in quickly after eating infected meat, a young animal can make a full recovery from the disease.

There is no treatment currently available for chronic or fetal toxoplasmosis.

Recovery from acute toxoplasmosis may involves IV fluids or other measures to help keep your pet healthy while fighting off the infection. Generally rest and avoiding contact with other animals is best.

Prevention is the best possible method for avoiding toxoplasmosis. Keeping litterboxes inaccessible to your dog, removing waste every day, and washing homegrown produce reduce the risk of you or your dog acquiring this infection. If you must feed your dog wild game or raw food, freeze any meat for at least two days before feeding. Pregnant women should take special care not to come in contact with cat feces or meat from wild animals.