Animals Ringworm

veterinarian checking a cat's ear for ringworms under UV lightIt may be surprising for some to learn that the skin infection known as ringworm, or dermatophytosis, is not actually a worm or parasite at all, but a fungus. The lesion will not always be in the shape of a ring, but it will appear scaly in the center with a red irritated color on the periphery.

“Household pets generally pick up the disease from other animals. Where the infection occurs on the skin there will be a bald patch, but sometimes they may just have a few broken hairs,” says Dr. Leon Russell, professor at the Texas A&M College of Veterinary Medicine & Biomedical Sciences.

Ringworm is highly contagious and can pass from person to person either through direct contact, through contact with an infected object, contact with an infected pet or infected soil. Humans can contract ringworm from animals very easily by touching the infected area directly or through contact with objects which have been exposed contaminated with the fungus or its spores.

Animal ringworm types, usually from a dog, cat, or rodent are more likely to be transmitted to young children. With children it is often found in the scalp region.

“Fungi that mostly live in human skin are called ‘anthropophilic’, those that live on animals are called ‘zoophilic’, and those that prefer to live in soil are called ‘geophilic’ fungi,” explains Russell.

The anthropophilic ringworm is mostly seen in developing countries such as Africa, or parts of Asia by human to human transmission. Many times this occurs from sharing hairbrushes or combs, and unless someone’s immune system is highly compromised then the disease is not life threatening.

“Tinea pedis, or athlete’s foot, is the most common form of ringworm found in humans and the most difficult to treat. The rash most often appears in the moist areas between the toes, though the rest of the foot can be infected as well. Itching and burning are typical symptoms,” says Russell.

Community swimming pools, used towels, health clubs, steam rooms and showers are common areas where athlete’s foot can be contracted.

“Rarely humans can transmit the disease to animals. An example of this might be if a person with athletes foot comes home, takes their shoes off, and scratches or rubs ol’ Fido with their bare foot,” says Russell.

Livestock such as cattle or horses are more likely to have ringworm when they are kept inside their stalls in the winter because of the rubbing up against wood and other stall materials.

“These cases are seen more in the Northern parts of the United States where the weather is colder. Generally, when the weather becomes warmer again and the animals are turned outside into the sunshine of pastures, the disease begins to clear up,” says Russell.

In horses ringworm is seen usually in places where rubbing may occur, such as where a saddle or bridle might touch. Adults are more likely to contract ringworm from a horse rather than children, due to occupational exposure and handling.

The effects of ringworm tend to be superficial ones of appearance, though, if not treated in animals it can easily spread and cause scar tissue.

Some people, mostly children, who contract ringworm from a pet can sometimes have a reaction with their skin tissue resulting in bulgy lesion-looking patches on the skin called Kerions. These are more severe in appearance compared to the normal reaction and can be very upsetting for the person.

“The treatment for ringworm in humans or animals is usually going to involve a topical medication. Oral medication may be needed if the ringworm is chronic, and therefore can sometimes take up to three or four months to clear. It is certainly not a reason to get rid of a dog or cat because it can be treated,” says Russell.

“The most common fungal species that may cause ringworm in dogs and cats are Microsporum canis. If you suspect that your pet has ringworm, a veterinarian will be able to determine if that is the case or not by examining the animal under special lighting wherein the fungus glows,” explains Russell.

If a pet is diagnosed with ringworm it is best to take steps to disinfect objects that the animal has been in contact with, using chemicals like chlorine diluted in water.

It is important to bring your pet, especially young pets, in for their vaccinations and checkups to ensure that diseases such as ringworm are not causing any problems.a cat diagnosed with ringworm



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*Top photo: Veterinarian checking a cat’s ear for ringworms under UV light. Bottom photo: Cat with a ringworm lesion on top of it’s left eye.

Precautionary Travel Tips

Most summer days are filled with outdoor activities and times spent on vacation. As the summer months starts to approach, it is necessary to understand the types of diseases that may affect your pets when they travel. So, if you’re the outdoor type and you like to take your pet with you, your pet may be bringing home more than memories as you venture through fields and streams.

When traveling, there are some diseases your pet may encounter says Dr. Leon Russell, professor at the Texas A&M College of Veterinary Medicine & Biomedical Sciences. If there is a possibility of contact with mosquitoes, ticks, or stagnant water during your travels, Russell says to take certain precautions.

If dogs and cats come into contact with mosquitoes they could be subjected to heartworm disease.

“Heartworm disease poses a threat to pets across the United States because no state is entirely heartworm-free,” Russell explains. “In areas where heartworm disease is highly endemic in dogs, up to 20 percent of the cats may also have the disease.”

Heartworm preventative medicine is available, but pets should be tested before they receive it.

Possible contact with wild animals could expose your pet to rabies.

“Effective vaccination of dogs and cats to prevent rabies is available and should always be kept current,” says Russell.

Rabies is transmitted by a bite from an infected animal and The Center for Disease Control (CDC) states that more than 90 percent of all animal cases reported annually to the CDC now occur in wildlife.

Water activities are fun, but certain waters may be infested with bacteria that could cause harm to your pet. According to Russell mud, muddy water, and stagnant water are prime sources for exposure to leptospira. This bacterial organism can enter the body through cuts, mucous membranes, eyes, or by ingesting contaminated water. Russell encourages a yearly vaccination with the appropriate strain of leptospirosis vaccine to reduce your pet’s chance of contracting this disease.

Giardiasis is another disease that is caused by a waterborne parasite found in untreated water such as creeks and ponds. It also occurs in mountainous areas where water supplies have become contaminated by infected animal feces.

“Chlorination of surface water will not prevent this disease,” cautions Russell. “Presently there are drugs to treat giardiasis, but none to prevent this intestinal disease.”

Borreliosis, or Lyme Disease, is an infection caused by a bacteria that is spread by the bite of an infected tick, and the disease is endemic in some areas of the United States explains Russell. Symptoms include fever, rash, listlessness, muscle stiffness, lack of appetite, and in severe cases arthritic-type joint pain.

“The best method of prevention is to avoid tick infested woods, brush, and tall grass,” Russell believes.  “Highly effective tick control products such as sprays, collars, and spot-on treatments are available through your veterinarian.”

Annual vaccination of your dog against the Lyme Disease is recommended if you live in or plan to visit endemic Lyme Disease areas in the United States. Check with your veterinarian about the need for the vaccination of your pets.

Russell suggests that once you return home, your pet should visit the veterinarian for examination to make sure no internal or external parasites were picked up while traveling.

“An examination is important, because worms can hide and they may not be detected until they cause a  clinical disease,” Russell adds  “Ticks can be too small to be easily seen by the untrained eye.  They must be eliminated before they transmit diseases such as Lyme Disease, tularemia, and Rocky Mountain Spotted Fever.”

“Also, avoid environments with ticks and mosquitoes (dawn and dusk) and allow your pet to swim only in clear, flowing water such as rivers or lakes,” notes Russell. “Be sure to bypass ponds or tanks.”

Time spent travelling with loved ones is important, but it is even more important to take the necessary precautions during vacation to avoid any pitfalls when you return home.



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Pet Diseases that Make People Sick

Sixty-four percent of American households own pets. This percentage is a large indication of the importance that pets have on today’s society.  People love their pets and their companionship provides positive health benefits to their owners. However, there are times that pets can cause harm to their owners because of the diseases they carry. It is important to be aware of some of the possible health problems that can be initiated by pets.

Roundworms can cause a disease that can be transmitted to humans by dogs and cats. Roundworms are parasites that can infect humans because their eggs live in the fecal contaminated soil and enter the body through accidental ingestion. Dogs and cats can carry adult worms in their intestinal tracts and shed the eggs in the animal’s feces. The damaging eggs can be transmitted to children after the eggs mature one to three weeks in the soil, and then infect soil ingesting children. Some symptoms include cough, shortness of breath, abdominal pain, nausea, diarrhea, blood in the stool, weight loss, fatigue, and presence of a worm in the victim’s vomit, stool, or behind the eye.

“In extreme cases, young children can lose an eye,” explains Dr. Leon Russell, professor in the veterinary integrative biosciences department at the Texas A&M College of Veterinary Medicine & Biomedical Sciences (CVM). “Children pick up the eggs from dogs and cats and their feces. The roundworms hatch out and become larvae, and they then migrate around the body until they enter the brain and cause damage. To avoid this, dogs and cats should be on a de-worming treatment. It is also important to teach children personal hygiene at a young age so that they can avoid infection and contamination.”

Hookworms can also cause health problems to humans via dogs and cats because they can bring them into the house. Hookworm larvae penetrate the skin and they migrate to the lungs. They then go into the trachea where they are swallowed and enter the digestive tract. The larvae finally enter the intestines where they mature into adult worms and live off of the host’s blood. Coughing, chest pain, and fever are sometimes experienced by infected people. Severe infections can lead to anemia and protein deficiency.

Toxoplasmosis also known as “litter box disease” is a rare disease that can be transmitted to humans by ingestion of the eggs one to two days after the eggs are passed in a cat’s stool. This parasite can also be acquired by eating undercooked meat, especially pork or mutton. General symptoms include enlarged lymph nodes in the head and neck, headache, mild illness with fever, muscle pain, and a sore throat. The severity of this disease heightens when a pregnant woman is infected because it can lead to an enlarged liver and spleen, eye damage, hearing loss, jaundice, and other health problems to the unborn child.

Generally, cat scratch disease is not as serious as other diseases, but it can still cause health problems. A cat infected with the bacteria Bartonella henselae can spread the disease to humans via a bite, scratch, or contact with the cat’s saliva on broken skin or through the eye. Most cases improve without treatment. If symptoms persist antibiotics may be subscribed to alleviate the conditions. Symptoms include a bump or a blister at the site of the injury, fatigue, fever, headache, swollen lymph nodes, and overall discomfort.

Giardiasis is a less publicized disease, but it is important to note because 20,000 cases were reported last year alone. People can contract this disease by drinking water from infected rivers where animals have defecated, especially dogs with diarrhea. Symptoms include abdominal pain, diarrhea, gas or bloating, headache, loss of appetite, fever, nausea, swollen abdomen, and vomiting. Sometimes medicine is used to cure the disease, but giardiasis usually goes away on its own.

“Giardiasis has been a real problem in day care centers,” said Russell. “One child will contract the disease and they will easily spread it to the other children.”

Some animals and their habitats are sources of exposure to Salmonella. There are over 2500 types of Salmonella bacteria. Salmonella can become a serious problem so it is important to be aware of the positive impact that cleanliness has on your health. Symptoms range from nausea to blood in the stool.

Many animals are carriers of Salmonella and pet turtles are very common carriers.

“Children with pet turtles need to be very careful when cleaning their aquariums,” notes Russell. “Children can easily pick up the bacteria if they don’t properly clean and sterilize the aquarium and its contents nor properly wash their hands afterward. Inadequate cleaning and sanitizing can also result in contamination of other nearby utensils that are exposed.”

As a lot of these symptoms are the same, people should consult their healthcare professional if they think they have contracted any of these or similar diseases.

“The best prevention for these diseases is to use common sense and to use good personal hygiene practices,” said Russell. “If you have pets it is also important to talk with your local veterinarian and your physician so your pet and you can keep up with your vaccinations.”


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Prevention The Key To Eliminating Rabies

Sunday (Sept. 28) is World Rabies Day, a global effort to raise awareness in support of animal and human rabies prevention. This day was set aside to educate people around the globe about the impact of rabies, how it can be prevented and how to eliminate the sources that contribute to the death of 55,000 humans from rabies worldwide.

In support of this effort, Dr. Leon Russell, a professor at the Texas A&M University College of Veterinary Medicine & Biomedical Sciences, shares some background on rabies and ways to prevent your pets and yourself from infection.

“Rabies in the USA is most common in the wildlife population and some of the more common hosts include skunks, raccoons, foxes and bats,” says Russell. “In other parts of the world however, especially in developing countries, dogs are the major host for rabies because of inadequate vaccination programs to protect them.”

There are different variants of rabies virus that are maintained by different wildlife hosts, and they tend to be located in different parts of the country. While raccoons are the major hosts in the Atlantic coast states, skunks dominate in the Midwestern states, while rabid bats are found throughout the U.S.

“All of these wildlife hosts can and do transmit rabies to domestic animals, especially dogs, cats and cattle,” notes Russell. “That is why it is so important to have your pets currently vaccinated, because dogs and cats can transmit rabies from wildlife to people if the pets are not protected.”

Because of the risk of infection and transmission, there are USDA licensed vaccines available to protect horses, dogs, cats, cattle, sheep and ferrets. Russell also notes that “in the past 15 years, there has been more rabies in cats than dogs because fewer pet owners have their cats vaccinated.”

Keeping your pets away from wildlife exposure year-round is also important. Rabies in wildlife does tend to follow seasonal peaks, but it still occurs throughout the year. For example, raccoon rabies tends to peak in early spring, skunk rabies is more frequent late spring and early summer and bat rabies peaks in late summer.

“These seasonal trends are most likely related to the population density and mating season in terrestrial animals, and the ‘swarming’ of bats related to their seasonal migration,” states Russell.

If you do see an animal that may be rabid, there are some behaviors you can observe. There are three stages of clinical rabies. In the first stage animals may wander and change their usual behavior.

“For example, in the first stage it not uncommon for shy dogs to become very friendly and wild animals may lose their fear of humans. Dogs may also ingest strange things, like rocks,” says Russell. “In the second stage, animals will attack just about anything, sometimes breaking their teeth in biting.”

The third stage of rabies is characterized by partial paralysis, usually involving the muscles of the jaw, so the animals may have a dropped jaw along with a glazed look in their eyes.

Russell adds that, “the animals may also have difficulty in walking, which sometimes gives skunks a wobbling gait or prevents cats from climbing trees. Unfortunately, regardless of the clinical signs, the rabid animal will die in a few days or even a few hours.”

If you see these signs in your animal, contact your veterinarian immediately. If it is not your animal, you can contact the local animal control agency or the local health department.

The good news, Russell explains, is that post-exposure treatment is very effective and safe in people. However, it must be prompt. The treatment starts with prompt first aid, which includes flushing the bite wounds out with liquid soap or detergent or just running water.

“People should contact their physicians as soon as possible. Post-exposure treatment is safe, but expensive, and consists of a rabies injection, plus a series of rabies five vaccine injections over the next four weeks. However, once clinical signs begin, there is currently no effective treatment for rabies,” notes Russell.

“There is also a procedure for handling dogs and cats exposed to rabid animals so you should promptly consult your veterinarian about any potentially exposed pets.”

He adds that the key is to remember is that prevention is the only way to keep rabies from spreading. Making sure that your animals’ vaccinations are current and keeping them away from wildlife can save them and you from the deadly disease.

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