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Pet Health Library

Dogs + Infectious Diseases

  • Giardiasis is an intestinal infection caused by a microscopic protozoan. These parasites attach themselves to the intestinal wall and the damage causes an acute, sudden onset of foul-smelling diarrhea. Diagnosis may be by routine fecal flotation or presumptively based on clinical signs. Fenbendazole and metronidazole are the drugs most commonly used to treat giardiasis.

  • Heartworm disease is a serious and potentially fatal disease. It is caused by a blood-borne parasite known as Dirofilaria immitis. Adult heartworms may live for five to seven years and, during this time, the female produces millions of offspring called microfilaria. You can prevent your dog from getting heartworms by using a heartworm preventive.

  • Heartworm disease is serious and potentially life-threatening to dogs. Treatment involves several components to combat potential bacterial infection, kill the heartworm larvae (microfilaria), kill the adult heartworms, and then test to confirm successful treatment. Complete rest for a dog undergoing treatment is essential. The prognosis for dogs after heartworm treatment is generally good if the pet owner follows all veterinary recommendations closely.

  • Hepatozoonosis in dogs is caused by ingestion of one of two organisms: H. americanum and H. canis. Both parasites are more common in the southern United States. The clinical sign and treatments for dogs with hepatozoonosis differ depending on the parasite species causing the infection. In either case, with appropriate treatment, the prognosis is generally good.

  • Canine herpesvirus, or canine herpes, is a systemic, often fatal disease of puppies caused by the canine herpes virus. It may remain latent in tissues after a dog is infected and may be passed on to other dogs, particularly to fetuses developing in the mother's uterus. Clinical signs in puppies include difficulty breathing, nasal discharge, anorexia, soft stools, crying, seizures, and sudden death. Symptoms in adult dogs include coughing and sneezing, miscarriage, lesions on the external genitalia, conjunctivitis, and corneal ulcers. The disease may be prevented by avoiding contact with infected dogs. Pregnant dogs should be isolated to prevent infection.

  • Histoplasmosis is an infection caused by histoplasma, a fungus found in moist soils and especially prevalent around the Ohio, Mississippi, Missouri, and St. Lawrence rivers, as well as the southern Great Lakes and Alberta. Fungal spores are inhaled or ingested and cause infection in many sites including the lungs, gastrointestinal tract, eyes, joints, and spleen. This handout outlines signs, diagnosis, treatment, and prognosis. Histoplasmosis is transmissible to humans, especially if they are immunocompromised.

  • Hookworm is a parasitic infection of the gastrointestinal tract of dogs. Their name is derived from the hook-like mouthparts they use to anchor themselves to the lining of the intestinal wall. How the infection is spread along with clinical signs, diagnosis, treatment, and prevention are covered in this handout.

  • Idoxuridine is an antiviral topical medication used to treat viral infections of the eye, such as feline herpesvirus-1 in cats. Idoxuridine comes as eye drops or can be compounded by your veterinarian into an eye ointment. Give as directed. Side effects of idoxuridine include eye irritation. Pregnant women should NOT handle this medication.

  • Imidocarb dipropionate is an injectable medication that is administered by a veterinarian to treat babesiosis in dogs. It is also used off-label to treat other protozoal infections in dogs, cats, and horses. Most common side effects include mild drooling, tearing, vomiting, or nasal drip. Do not use in pets with exposure to cholinesterase-inhibiting drugs, pesticides, or chemicals. If a negative reaction occurs, please call your veterinary office.

  • Vaccinations are important to prevent serious illness in dogs. Even dogs that spend all their time indoors should be vaccinated. Some viruses can be carried into your home on inanimate objects such as shoes and clothing, therefore infecting your dog without him coming into contact with another animal. Your veterinarian is your most important resource in determining what vaccinations you need to give your dog to keep him protected.