By Dr. Susanne Krägeloh
Hello, my name is Dr. Susanne Krägeloh, and I have been working in Beaumont since August 2020. My welcome to the new workplace has been warm, and I really appreciate to be in a community like Beaumont, where the people are so nice, friendly and helpful. Working in the midst of a pandemic has hindered to get to know people more in depths, but we are getting there.
It certainly has been a challenging year for everyone; I am sure our pets feel it too. Having said that at this time we are blessed with nice fall weather, and are preparing for the winter months. So, a lot of us are drawn outside for walks or camping, and enjoying the outdoors, together with our dogs, and our indooroutdoor cats will also be roaming to get some hunting in.
Who has probably not been affected by the pandemic are little critters living on or inside our pets: parasites. There are a multitude of parasites here in Alberta, and mostly we are unaware of them since they are not visible in most cases. External parasites are the ones living on the outside of our pets: mites, fleas and ticks as well as lice. We are more aware of them since they can cause visible changes for our pets: itchiness is the most common sign.
There are several groups of ectoparasites: Fleas, ticks, mites and lice are the main ones we see frequently. They can affect a specific host only (which means they only feed on one species of animals like dogs only) or they can affect several different species of hosts like dogs, cats, wildlife and also humans.
Fleas are a common parasite of dogs and cats, as well as other mammals (wildlife: coyotes, foxes, small rodents). Their bite can cause itch and also hypersensitivity reactions of the skin, which is frequently seen in dogs (as well as in humans). Adult fleas feed on the hosts blood, and lay their eggs on the host; then the eggs fall into the environment (inside and outside, depending where the host lives). Larvae hatch from the eggs, and the larvae feed on organic debris. Then they form pupae, from which adult fleas emerge as early as after one to two weeks. The adult fleas need a host for a blood meal, in order to produce eggs. Then the life cycle is complete and starts over. Adult fleas can live 2-3 months, and can produce 40-50 eggs per day – a stunning number of up to 1500 eggs within 3 months!
Besides being a nuisance, fleas can also transmit diseases: for me the most well known is the plague (caused by a bacterium called Yersinia pestis), but also salmonella, a bacterium which can cause diarrhea, or blood parasites which can cause anemia (lack of red blood cells) among others. Some fleas can even transmit tapeworms!
Ticks are also a parasite present in Alberta, and lately we have been hearing a lot about them. They seem to have become more prevalent here. We are concerned about the transmission of diseases by ticks, with Lyme disease being the most well-known disease, but there are other diseases they can transmit as well, like Rocky Mountain spotted fever, Tularemia or Anaplasmosis. These diseases are caused by pathogens transmitted by the ticks, when the ticks are feeding; and the pathogens are released into the bloodstream of the host after several hours of feeding.
There are several different species of ticks in Alberta, and they all have the potential to transmit diseases. Most ticks are acquired from being outdoors; they live in the woods or in grassy areas, climb up on vegetation and let themselves fall onto a passing host. The brown dog tick (Rhipicephalus sanguinueus) though can live inside homes or kennels, where dogs are, in cracks and crevices of any building, and can survive there for quite some time.
The life cycle of ticks can be very specific, generally there are eggs, larvae, nymphs and adults. Larvae, nymphs and adults feed on a host, then fall off to molt into the next stage and move on. Adults will mate, then when the female is engorged, she will fall off the host and lay a cluster of eggs. She will then die, but the life cycle goes on.
Mites are usually transferred in younger animals by close contact, the most well-known mite here is the ear mite (Otodectes cynotis). Other mites can infect the skin, which can cause mange. Signs of infestation are head shaking and itching of the ears with ear mites and hair loss and itchiness with demodicosis or sarcoptic mange. Fortunately, mites are relatively host specific, which means they do not affect people (with the exception of Sarcoptes scabiei which can cause scabies in people as well). Therefore, it is always a good idea to wear gloves when handling a dog with suspected mange.
Lice are also in the category of ectoparasites. They are extremely host specific and cannot survive away from their host. However, a severe infestation with lice can cause itchiness. The biggest concern here is transfer of eggs through grooming equipment like combs or brushes.
All of these critters are unpleasant to have around, but they are easily treated or prevented. There are a multitude of products available, in different forms (usually topical products which get applied onto the skin of the animal or chewable tablets), and usually are given on a monthly basis, either all through the year or in the months when these parasites are most active, which is still possibly from March through November. Fleas and mites can occur right through the whole year, and ticks are active at temperatures as low as 4 degrees Celsius/40 F. We as veterinarians can help you find the right prevention product for your pets.
This is a very general overview of these creepy crawlies; it is a good thing that we have the ability to treat and prevent them. Next time I will give some information on internal parasites but for now I want to wish everyone a pleasant and parasite free October!