External parasites are those groups of bugs that may infest the skin or ears (the external or ‘outer’ part of the body) of animals. These are different from “internal parasites”, mainly worms, which infest the inside (primarily the gut/intestines) of animals. For the purpose of this article we will only focus on those affecting dogs and cats.
Ticks and fleas are the most common external parasites that we need to prevent in our beloved pets. Not only do they cause irritation to the animal but they often carry with them certain diseases. Unfortunately even the best looked after pet is at risk of infestation (picking up and carrying ticks and fleas). This is because they are present in fields, parks and anywhere else that may have long grass or other animals that form part of the pest’s life-cycle (also known as an intermediate host).
Ticks may carry smaller parasites namely babesia or Erhlichia. A pet may even become infected with both. Information about these diseases may be found in a separate article. Babesia (otherwise known as ‘tick bite fever’ or ‘bosluiskoors’) can be fatal if left untreated. Erhlichia is also a very debilitating disease.
Fleas may carry and transmit tapeworm which can also be quite debilitating and heavy infection can also lead to death if left untreated. Fleas can also cause extreme discomfort by causing severe itching and some pets may develop an allergic reaction as well.
Fortunately both ticks and fleas are preventable with products that can be bought over the counter at most vet practices or vet shops. These may be in a “spot-on” application which is applied to skin, or a tablet form whereby the active ingredient (the drug that actually kills the parasite) accumulates in the skin, or a collar put around the neck. Most products need to be repeated monthly but some may be effective for 3 to 6 months.
Mites are another group of bugs that may infest the ears or skin of our pets. Cats generally struggle with those mites that accumulate and cause irritation in the ears (known as ear mites). Dogs however may be infected with one of two different mites that burrow into the hair follicles of the skin. These mites cause a condition known as ‘mange’. Demodex is a mite that mostly affects puppies and dogs living in poorer conditions whose immune systems are weaker. It is not considered contagious. Scabies on the other hand is a mite that is transferable to humans. It causes a pet to be extremely itchy, unlike demodex, which does not tend to cause itching. Both types of mange cause hair loss which may be focal (small local area) or generalised (the whole pet).
In order to diagnose ear mites, a vet will look into the ears with an instrument called an otoscope. Although quite small, the mites may be seen walking around. They also tend to cause an increase in brown ear wax.
Mange is diagnosed by the vet performing a procedure called a ‘skin scrape’ which allows the vet to visualise the mite under the microscope. In some cases the pet may need a course of antibiotic as well if there is a secondary skin infection due to the skin damage caused by the mite.
Many of the products that are effective for ticks and fleas are effective against mange and ear mites. The treatment is however normally longer than that for ticks and fleas.
Prevention is better than cure. Keep up to date with products effective against external parasites.