Arthropods include insects as well as arachnids (spiders, ticks, and mites). As summer approaches and pets are spending more time outdoors, make sure you know what to help your pet avoid!
Mosquitoes: Mosquitoes can transmit a variety of pathogens to mammals. For dog and cat owners, the biggest concern we have with mosquitoes is the transmission of heartworm disease. The Companion Animal Parasite Council (CAPC) predicts an above average heartworm disease activity nationwide for 2017. We recommend year-round heartworm prevention for all dogs and cats.
Fleas: These pesky, itchy insects can wreak havoc on a pet’s skin, especially if the pet has an allergy to the flea saliva. Since female fleas can lay 40 to 50 eggs per day, fleas will rapidly infest the environment. Fleas also have the potential to transmit zoonotic diseases such as Bartonellosis, Tularemia, and Plague. Year-round prevention will protect your pet and keep infestations from occurring.
Ticks: By now you are probably familiar with the idea that ticks can transmit many different diseases. Different species of ticks tend to have certain diseases that they can transmit (for example, the blacklegged tick (deer tick), is infamous for transmitting Borrelia burgdorferii, the spirochete bacteria that causes Lyme disease). Some of the more common tick-borne illnesses include Lyme disease, Rocky Mountain Spotted Fever, Ehrlichiosis, and Anaplasmosis. We recommend testing dogs annually with the 4DX heartworm test that also tests for exposure to Lyme, Ehrlichia, and Anaplasma. Year-round tick prevention is also recommended.
Mites: There are a number of mite species that can affect dogs and cats. For dogs, sarcoptic mange is a contagious, intensely itchy condition caused by the Sarcoptes scabiei mite. Both dogs and cats can also have problems from Demodex mites. Demodex mites are normally present in low numbers in hair follicles, but some animals can develop an overgrowth which can cause skin lesions and itching. All mites are typically diagnosed through a technique called skin scraping, followed by visualization of the mites with microscopic magnification.
Lice: Lice are typically species-specific because they are intimately adapted to their particular host species. Lice are classified as biting (chewing) or sucking based on the type of mouthparts they have. Lice can cause itching with secondary skin issues. Lice tend to be less common than parasites such as fleas and ticks.
Spiders: Spider bites are uncommon as most spiders would prefer to run away. Although many spiders produce venom, their bites are not typically harmful. In North Carolina, we have only two spider species that are considered harmful: the Black Widow and the Brown Recluse. The Black Widow has a red to orange hourglass-shaped marking on its “belly”. The brown recluse has a violin-shaped marking on its back with the “handle” pointing towards the rear of the spider.
Stinging insects with venom: This group includes insects such as bees, wasps, hornets, and fire ants – anything that has a stinger and injects venom. Reactions can range from minimal local irritation to a severe allergic or anaphylactic reaction. Always remove any stinger that is left behind and seek medical attention immediately if your pet is showing signs of a reaction.
- Flies that can cause myiasis (Warning! This may be a bit gross to some…): Myiasis is basically the idea of fly larvae utilizing the tissue of living vertebrates as a food source. There are 3 major families of flies that cause myiasis: Calliphoridae, Oestridae, and Sarcophagidae. Flies in the Oestridae family include the familiar bot flies and cuterebra which create boil-like swellings where they enter the skin. The Calliphoridae and Sarcophagidae tend to lay eggs on damaged tissues. However, there is one species of Calliphorid fly called Cochliomyia hominivorax, the New World Screwworm Fly, that the U.S. is always on the lookout for because it will also lay eggs on healthy tissue. This fly was eradicated from the U.S. in 1983, but last year it appeared again in the Florida Keys in the Key deer population. Thankfully it has again been eradicated!
Cockroaches: These insects do have the potential to carry germs and possibly transmit intestinal parasites by serving as accidental or intermediate parasite hosts. For example, cockroaches may be accidental hosts to roundworms when they ingest the eggs and then pass the eggs along to whatever animal ingests the cockroach.
Caterpillars: Some species of caterpillars contain poison sacs that are attached to the quill-like hairs (called setae). If brushed against, the broken setae can release the poison. One of the most poisonous caterpillars in North Carolina is the puss caterpillar shown here.
References:
- Carolinas Poison Center
- Primary screwworm University of Florida Entomology Department
- Hamu, H., S. Debalke, E. Zemene, B. Birlie, Z. Mekonnen, and D. Yewhalaw. Isolation of intestinal parasites of public health importance from cockroaches (Blattella germanica) in Jimma Town, Southwestern Ethiopia. J. Parasitol. Research 2014:186240
- Toxocara cati, American Association of Veterinary Pathologists
Author: Dr. C. Noureddine, DVM, MS