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Pet Health Library

Dogs + Infectious Diseases

  • Leishmaniasis is a disease caused by a protozoan parasite transmitted by sandflies and is most commonly seen in the Mediterranean, Middle East, and South and Central America. It has been reported in some parts of the United States. Clinical signs include hard skin nodules, weakness, decreased appetite, vomiting, diarrhea, and more. Diagnosis is based on travel history, clinical signs, and diagnostic testing. The goal of treatment is to resolve clinical signs. Prognosis is guarded to grave depending on the severity of the disease.

  • Leptospirosis is a bacterial disease of dogs and other mammals that primarily affects the liver or kidneys. The bacteria (Leptospira) that cause leptospirosis thrive in water. Infected or recovered carrier dogs may act as a source of the infection. Antibiotics such as penicillin, ampicillin, and amoxicillin are reasonably effective against the acute stages of leptospirosis, if started early, although most affected dogs require intensive care in the veterinary hospital. This disease can be transmitted to humans.

  • The bacterium that causes Lyme disease can be transmitted to dogs through the bite of an infected tick, most commonly the deer tick (black-legged tick), which is found in the midwestern and eastern United States and throughout Canada. The disease typically causes pain and swelling in the affected dog's joints along with decreased appetite and fever. The kidneys are sometimes affected, in which case the disease is often fatal. Diagnostic testing, treatment, and ways to prevent Lyme disease in your dog, including instructions for tick removal, are explained in this handout.

  • Melioidosis is a bacterial infection that is typically associated with tropical regions. The bacteria that causes melioidosis, Burkholderia pseudomallei, is usually found in soil and water. The clinical signs of this condition, along with transmission, diagnosis, treatment, and prognosis, are outlined in this handout.

  • Parvovirus may affect dogs of all ages but is most common in unvaccinated dogs less than one year of age. Young puppies under five months of age are usually the most severely affected and difficult to treat. Clinical signs can vary but generally include severe vomiting and diarrhea; the diarrhea often has a powerful smell, may contain lots of mucus, and may or may not contain blood. Most dogs with CPV infection recover if aggressive treatment is used and if therapy is started before severe septicemia and dehydration occur.

  • The Ebola virus is very contagious and is transmitted through blood, body fluids, and tissues, but not through air, water, or food. Ebola affects humans, non-human primates, and is carried by fruit bats. Other species do not appear to be affected, although there has been evidence of exposure to the disease in dogs, cats, and other domestic animals. Domestic animals are not believed to transmit the virus; however, there is a risk that they could transmit body fluids such as saliva on their fur to other humans. Any potential exposure to Ebola should be reported to your veterinarian who will contact the Center for Disease Control (CDC).

  • The American Animal Hospital Association and American Veterinary Medical Association have established guidelines to standardize preventive health care for dogs, helping them to live longer, healthier lives. This handout provides an overview of the recommendations within these guidelines and why they are so important.

  • Pythiosis is a waterborne infection that can infect the GI tract or skin of dogs. It can cause extreme weight loss, vomiting, diarrhea or skin lesions such as ulcerating nodules and draining tracts. This disease is more common in southern regions. Treatment involves surgical removal of all affected material if possible, including limb amputation if indicated. Different antifungal therapies have shown some efficacy and need to be continued long-term. Prognosis for resolution of pythiosis is guarded to poor.

  • Rabies is one of the most devastating viral diseases affecting mammals, including dogs and humans. It is a fatal disease caused by infection with the rabies virus. Following a bite from a rabid animal, the disease progresses in stages. Vaccination is the cornerstone of rabies prevention.

  • Ringworm infections in cats are caused by a fungus, not a worm. They can be easily recognized, though definitive testing by fungal culture is recommended. Ringworm is highly contagious and can be spread between animals and from animals to people. The clinical signs, diagnosis, treatment, and risks are explained in this handout.