Perhaps you recently saw the news story where a man lost both his arms and his legs from an infection caused by a lick from a dog, or the 2 year old toddler that died after visiting a petting zoo at the local fair, but those are certainly not the only cases!
Zoonotic diseases are those that are transmittable from animals to humans. Most animals, including wildlife, farm animals and domestic pets, can carry viruses, bacteria and parasites that can affect humans.
The usual method of transmission is through direct contact with infected feces or saliva and sometimes through direct contact with the animal. Here are some of the diseases that families with pets are most likely to encounter:
Leptospirosis is a bacterium that is common to all parts of the world and can be serious for humans and their pets. It causes flu-like symptoms and can become a life-threatening infection affecting the kidneys, heart, brain or liver. The bacteria are spread through the urine of infected animals, often rats, either through direct contact or contaminated water or soil. The infection is rare in cats, but infected dogs may have no symptoms, or may experience vomiting, fever, diarrhea, abdominal pain, weakness and loss of appetite.
Pets may be vaccinated against the disease but it is not 100% effective. If your pet becomes ill with leptospirosis, you should wear disposable gloves if you may come in contact with his blood or urine, and wash your hands thoroughly after handling your pet. Clean any contaminated surfaces with an antibacterial solution or a 1:10 bleach solution. Leptospirosis is treatable with antibiotic medicines.
Keep your cat well fed so its desire for catching mice is kept to a minimum. Eliminate the rodent population in your home and yard so pets won’t be exposed to the bacteria spread by their urine.
Many kinds of animals can transmit the rabies virus to humans. Rabies in dogs is rare in the U.S. but is still common in developing countries, including Africa, Latin America, and Asia. In wildlife, it is often carried by bats, squirrels, raccoons, skunks, and coyotes, but any warm-blooded animal can become infected. The virus is transmitted through the bite of a rabid animal and symptoms begin to develop in one to three months. The first signs of rabies infection are a headache and fever. The virus quickly begins to affect the nervous system and the victim becomes sleepy, agitated and confused. Once the victim begins to exhibit these symptoms the disease is almost always fatal.
Vaccinate your pets against rabies and keep them from coming in contact with stray cats and dogs or wild animals. Teach your children not to approach wild animals or strange dogs and cats which may not be vaccinated. If you are bitten, wash the area with soap and water and call your doctor immediately. Contain the animal if possible so that it may be evaluated for a rabies infection.
Salmonella is a bacteria that humans usually encounter from a contaminated food source, but dogs and cats can transmit the disease to their owners through their feces and saliva. Reptiles often carry the bacteria in their intestines. Infected animals may not have symptoms but can be carriers. Symptoms of salmonellosis in humans include fever, abdominal pain, diarrhea, and dehydration. Many people recover without treatment, but hospitalization may be necessary if the patient becomes severely dehydrated or the disease infects the blood system.
Keep your dog or cat free from salmonella infection by never feeding them raw meat or eggs and not allowing them to rummage in the garbage where they may pick up the bacteria. Protect your family by not allowing your pet to lick people, the usual method of transmission from pets to their owners.
Don’t allow pet reptiles to roam freely in your home where they may spread the organism. Always wash your hands after handling reptiles or other pets, especially before preparing food. Do not allow very small children, who tend to put their hands in their mouths, to handle pet reptiles or those they find in nature. Never bathe pets or wash their cages in the kitchen sink. It is recommended that homes with children under five years old, senior citizens, or member with impaired immune systems do not keep reptiles as pets unless they are extremely vigilant about the care of the animals.
Ringworm is not a worm, as the name implies, but a fungal infection that affects the skin and scalp. It is transmitted by direct contact with an infected pet’s skin or hair and causes a ring-shaped rash that may be either wet and crusty, or dry and scaly. On the scalp, it will create a bald patch of scaly skin. Ringworm can also affect the nail, making them thick and discolored.
Prevent ringworm by keeping your pets well-groomed and avoid touching pets with bald patches in their fur. The disease will usually resolve in about four weeks with over-the-counter fungal medications. Medical treatment with prescription antifungal drugs if the infection is severe or persistent. Wash bed linens and nightclothes every day and do not share hairbrushes, towels, hats, or other personal items with others to avoid spreading the fungus to others.
Psittacosis, also known as parrot fever, is caused by an organism that infects many species of birds, but in most cases involve members of the parrot family. Symptoms in birds include eye and nose discharge, a ruffled appearance, lack of appetite, and diarrhea. Some birds may carry the organism without showing symptoms. The infection is spread through the droppings of a carrier bird and the living organism may be present for several months in droppings that have turned to dust.
Humans contract the disease by inhaling the infected airborne dust. Most cases in humans resolve without treatment but may become serious, developing into pneumonia or other medical conditions if untreated. Symptoms in humans include fever, chest pain, a dry cough, and nausea. Antibiotic treatment is available for severe cases. The disease is more serious in children and adults with compromised immune systems. Infection does not give immunity to further exposure to the disease. Keep your bird’s cage clean so that droppings do not become dry and airborne.
Giardia is a parasite that can infect the intestinal tract of most wildlife, livestock, and household pets. In humans, the infection commonly results when a person swallows water that has been contaminated by infected feces or may be passed from person to person in crowded environments such as daycare centers. A pet who drinks from a contaminated body of water may become infected with the parasite. People and pets infected with giardia will suffer from acute gastroenteritis and diarrhea, with fever being less common. An acute case may become chronic, with resulting weight loss, general feeling of ill health, bloating, nausea and flatulence, and may require medical intervention.
Follow basic hygiene practices to prevent spreading giardia to your family. Wash your hands after cleaning up pet feces, after using the bathroom or changing diapers, and before preparing food. Washing dishes in water over 130 degrees F or in a dishwasher will kill giardia, and hard surfaces may be disinfected with a 1:32 bleach solution. People who enjoy swimming in natural bodies of water should avoid getting water in their mouth, and campers and hikers should use chlorine tablets to purify potentially unsafe water used for cooking or drinking.
Fleas can be the bane of a pet owner’s existence. Many pet owners don’t realize they have a flea problem until their dog or cat is away from the home for a while or believe that getting rid of the pet will get rid of the problem. If a dog or cat host is not available, the fleas may infest the human family members. Flea bites will appear as tiny bumps that itch severely.
The bites may appear as a rash at the waist, ankles, armpits, and at the bends of the elbows and knees. Scratching may lead to secondary skin infections. The only real solution to the problem is to eliminate the flea infestation in your home. The life cycle of the flea bites is to soothe them. Wear socks all the time and wash bedding daily until the problem is under control.
Fleas may also transmit tapeworm infections to animals as well as humans. Most infections result from eating undercooked meat that contains tapeworm larvae. The head of the tapeworm grabs on to the lining of the intestine and grows in segments which break off and are excreted in feces. The segments contain eggs sacs, which will not infect mammals.
Flea larvae will ingest the eggs, where the tapeworm larvae continue their life cycle until they are ready to infect humans and other mammals. When a flea is swallowed by a host, the tapeworm larvae migrate to the intestines and the cycle begins again in the new host. The tapeworm is not passed from pet to owner, but a pet owner who accidentally swallows a flea may become infected with tapeworm.
Most people and animals do not exhibit symptoms of tapeworm but may see small moving segments that look like rice grains in their stool. Other signs may include nausea, weakness, diarrhea, weight loss, abdominal pain, and loss of appetite. More serious infestations may cause organ and tissue damage, fever, and seizures. Medications are available to kill tapeworms, and one treatment will eliminate existing worms. Pets are usually given repeat treatments since they may become reinfested.
Toxoplasmosis is caused by a single-celled parasite transmitted by cats in their feces. Cats usually show no symptoms of the disease and humans with healthy immune systems are seldom affected by the parasite, but it can have serious consequences for pregnant women and people with compromised immune systems.
The disease causes flu-like that can last a month or longer and may damage the brain, eyes, and other organs. A small percentage of infants who are exposed to the parasite while in the womb may have eye or brain damage at birth. Most show no symptoms at birth but may develop the disease later in life.
Being pregnant doesn’t mean you have to give up a beloved cat. Keep your cat indoors so he won’t catch birds or rodents that may carry the parasite. A cat who infected only excretes the parasite for a couple of weeks which then goes away without treatment. Another family member should take over the litter-box duty, or the expectant mother may clean it every day since the parasite takes a day or more after being passed to become infectious.
Wash hand thoroughly after handling the litter box, especially before preparing food or eating. Wear gardening gloves when working outdoors in the soil to avoid contamination from neighborhood cats who may have used your yard as their litter box.
Catch Scratch Disease
Cat Scratch Disease is a bacterial infection that occurs most often in children who play with cats and are more likely to be bitten or scratched than an adult. The bacteria may be transmitted from cat to cat by fleas and lives in the animal’s saliva.
The disease is not contagious between humans. You can become infected by being bitten by the animal, from a scratch after the animal has licked his paw, or by rubbing your eyes after petting an infected cat (the cat will spread the bacteria over his fur while grooming).
A small, usually painless, bum resembling an insect bite appears on the skin several days after the scratch or bite. The lymph nodes close to the site will begin to swell and become tender in a couple of weeks. The skin over the infected nodes may become red and warm.
Cat Scratch Disease is often mild and resolves itself without medical treatment. The child (or older patient) may suffer fatigue, headache, rash, sore throat, a low fever, or loss of appetite. You can make the patient more comfortable with warm compresses applied to the swelling, and acetaminophen or ibuprofen.
Let the child play if he feels up to it; bed rest is not necessary unless the child is experiencing much fatigue. More severe infections may require medical treatment with antibiotics, and the doctor may drain fluid-filled nodes with a needle if they become especially swollen and painful. Once a person has recovered from the infection he will have life-long immunity to the disease.
Prevent your cat from becoming infected by keeping it free of fleas. Teach your children to play gently with cats to avoid being scratched or bitten, and to stay away from stray cats. Wash your hands after handling a cat, since it may spread the infected saliva over its fur while grooming. Wash the area with soap and water if the child is scratched or bitten. Call a doctor immediately if the cat is not known to have a rabies vaccination, or if the redness continues to spread after a couple of days.
Tips for Preventing the Spread of Zoonotic Diseases
Even a cat or dog that is kept indoors and never exposed to other animals may become infected by a single flea that is inadvertently brought home on a family member’s shoes or clothing. Fleas may lay eggs on the pet which will fall off into the carpeting and upholstery. It may require the services of a professional exterminator to eliminate a severe flea infestation, but the population can be kept under control with a variety of chemical insecticides.
Foggers are not 100% effective, and flea collars will kill the eggs but are not effective at killing adult fleas. Always follow instructions precisely when using flea-killing products. Disrupt the life cycle of the fleas with medications available from your veterinarian and control the flea population to reduce the chance of your family or pet succumbing to flea-transmitted parasites and diseases.
Consult a veterinarian if your pet has diarrhea, vomiting, or other signs of illness that last more than a day or two. Don’t allow your pet to roam freely where it may encounter wildlife, livestock, contaminated water or infected feces and bring home potentially life-threatening organisms.
Keep your pets well groomed, watching for any signs of flea infestations. You may not see the actual fleas, but “flea dirt”, tiny black specks on the pet’s skin that turn red when touched with a wet tissue. Inspect your pet’s skin regularly for red, scaly, or balding patches or other signs of skin infection. If your pet seems ill for more than a day or two, take him to the vet for a check-up to catch any infections before they have a chance to spread to human family members.
Cook meats thoroughly before feeding them to your pet or family and use basic kitchen hygiene to avoid spreading diseases that may be transmitted by raw meat. And don’t let Fido rummage through the garbage can!
Teach your children to wash their hands after playing with any animal, and discourage them from allowing your dog to lick their faces. Doggy kisses are sweet, but may be filled with dangerous organisms!