Diseases Common to Dogs & Humans

There are many bacterial, viral and parasitic illnesses that can affect both dogs and humans. Although some of these infections are mild, others can cause serious illness or death if left untreated. A medical professional can diagnose the disease and can prescribe a course of treatment.

Leptospirosis

• Leptospirosis is caused by a bacterium called leptospira. This disease is common in warm or tropical areas. Dogs contract leptospirosis by eating infected animal matter, by being in contact with the urine of a diseased animal or by drinking contaminated water. Humans usually get the disease by drinking, swimming or bathing in water that an infected animal has urinated in.

  The symptoms of leptospirosis in humans occur in phases. The first phase is characterized by fever, muscle aches, vomiting, chills, and diarrhea. The person may recover after becoming ill, but then relapse into the second phase of the disease, which often involves kidney or liver failure.

  Dogs with leptospirosis have many of the same symptoms, including an initial onset of fever, muscle pain and vomiting. Like humans, they may also develop kidney or liver failure. The disease is treated in both dogs and humans with antibiotics such as penicillin. (See references 1 and 2)

Rocky Mountain Spotted Fever

• Rocky Mountain spotted fever is caused by an organism called Rickettsia rickettsii. The infection is spread through the bite of the Rocky Mountain spotted fever tick. It is a severe illness that can cause death in both humans and animals.

  The initial symptoms of Rocky Mountain spotted fever in humans are high fever, chills, nausea, vomiting, and sensitivity to light. As the infection progresses, the person may develop diarrhea or generalized muscle pain, as well as a spotted or blotchy rash that starts on the hands and feet. The disease can cause brain damage, gangrene, failure of the major organs and death if left untreated.

  Dogs with acute Rocky Mountain spotted fever may have muscle pain, fever, swollen lymph nodes and a loss of appetite. As the disease progresses, the dog may develop neurological symptoms such as seizures. Many dogs also have hemorrhaging in the retina. The disease is treatable with the antibiotic doxycycline if it is caught in the early stages. (See references 3 and 4)

Lyme Disease

• Lyme disease is caused by a bacterium called Borrelia burgdorferi. It is transmitted to humans and animals through the bites of infected deer ticks.

  Humans who are bitten by infected ticks usually have a reddish-colored ring that starts at the site of the tick bite and gradually expands. The victim will develop smaller lesions all over the body several weeks or months after the appearance of the first symptom, and in severe cases, the person can contract meningitis or Bell's palsy. Arthritis and encephalopathy (personality changes or sleep disturbances) are the final symptoms of Lyme's disease. These symptoms can develop many years after the original infection.

  Dogs with Lyme disease usually have fever, a lack of energy, and a loss of appetite in the early stages. The dog may also develop arthritis, neurological issues or heart problems because of the infection. The infection is treated using the antibiotics doxycycline or amoxicillin. (See reference 5)