Pets and Diseases
Pet Related Diseaess
Many human infections can pass between humans and animals. A study done in 1987 suggested there were about 4 million pet related infections in the United States that year. The number of household pets has only grown since that time. In 2002 the number of dogs was estimated at 62 million and the number of cats at 68 million in the United States. Exotic animals present even more of a problem because they can transmit disease from one area of the world to another. This makes diagnosis very difficult at times. This article will take a brief look at various pet related diseases from some of the more common parasites, bacteria, viruses.
Parasites are organisms that live in or on other organisms. Toxoplasmosis is a very common parasitic infection. Cat feces are the vector to humans due to the excretion of the spores in the cat feces. Thus, cleaning the litter box and gardening in contaminated soil are the main risks in developing the disease. Toxoplasmosis in adults is usually asymptomatic, but may cause a mono-like illness. Pregnant women should avoiding cleaning the litter box because infection in the third trimester can cause serious congenital problems.
Round worms are found in both dogs and cats. Puppies are often born infected. Children are especially prone to infection because they often handle animal feces or soil contaminated with animal feces. The immature stage of the round worms is called larvae. The larvae may migrate from the intestine to the liver, lungs or eyes. This may result in serious illness.
Hookworms cause an infection of the skin. Fecal material from infected dogs or cats gets into the soil in the form of cysts. Walking barefoot in this contaminated soil allows the cysts to gain access through a break in the hosts skin. The larvae cause a reddish itchy raised area at the site of the infection. The larvae then migrate under the skin leaving a reddish irritated track through the skin.
Tape worms are common in both dogs and cats. Humans become infected through fecal contamination or through fleas. Human infections are usually not serious but can on occasion cause serious heart and liver problems.
Fungal infections with ring worm are the most common shared infection among humans and domestic pets. It appears to be most common in children. It usually results in a minor superficial infection that can be treated with topical medication.
Bacterial infections are another common source of infection spread between humans and animals. Salmonella is common in turtles, iguanas, chicks, ducklings, dogs and cats. Campylobacter is found in cats and dogs. Both of these bacteria are common causes of gastroenteritis in humans. In fact there are about 200,000 cases of gastroenteritis per year related to these bacteria in humans per year. Cat scratch fever is related to a bacteria carried in cat saliva. This bacterium is called Bartonella henselae. The infection is usually caused from a scratch after the cat has been licking its claws. The infection may show up weeks later and often presents with fever, malaise and swollen lymph nodes. Methicillin resistant staphylococcus aureus ( MRSA ) can be passed to humans from cats and dogs. In cases of recurred infections in households the pet may be the carrier that causes the recurrences. Psittacosis is also known as parrot fever. It presents in humans as a flu like syndrome and occasionally pneumonia. It can be found in parrots, cockatiels, parakeets and macaws. Mycobacterium marinum is an infection of the skin resulting from exposure to fish tank water. It usually causes cutaneus granulomas but can become life threatening in immunocompromised individuals.
Viral infections such as rabies are uncommon in properly cared for pets because of vaccinations. However, pets interact with local wildlife and may develop these more serious infections. Lymphocytic choriomeningitis is a virus that hamsters, guinea pigs and mice carry. This virus in humans usually presents as flu-like syndrome. This disease has caused more serious infections in those humans with a weakened immune system.
The best way to prevent pet related diseases is good flea/tick control and good veterinary care for pets. Good hand washing after handling pet waste and proper disposal of the waste are also important ways to minimize pet related disease. Pregnant women, infants, HIV patients, transplant patients, patients on chemotherapy or chronic steroids, and the elderly should avoid contact with any pet waste, reptiles, chicks, ducklings, kittens, puppies and any animal that appears ill. Any sick pet should be seen by a vet for proper diagnosis and treatment. If you become ill while caring for a sick pet you should see your family doctor and let him know of the ill pet.
Pets provide great companionship to millions of families in the United States. They have been shown to reduce stress and depression. However, on occasion they may carrier certain infections that can be spread to their human house mates. Good cleaning techniques and proper veterinary care can prevent the vast majority of these infections.families in the United States. They have been shown to reduce stress and depression. However, on occasion they may carrier certain infections that can be spread to their human house mates. Good cleaning techniques and proper veterinary care can prevent the vast majority of these infections.
Mark Smith, MD