Ask a UW Veterinarian: Protecting Pets from Insect Pests



This expert response comes from Amy Nichelason, a veterinarian with UW Veterinary Care’s Primary Care service.

Question: As the weather warms and more time is spent outdoors, how can we best protect our animal companions from diseases spread by insects?

Answer: Several bugs and parasites can spread disease to your pet. These include mosquitoes (which can transmit heartworm), ticks (Lyme disease, anaplasmosis, or ehrlichiosis), and fleas (tapeworms). Mites, lice, and fleas can also cause generalized itchiness to your pet.

Insect prevention should occur year-round. Although insects and arachnids are not typically active during winter months in Wisconsin, several tick species can become active when the temperature is above freezing. Knowing when to begin preventative treatment during temperature fluctuations can be challenging. Instead, we recommend year-round prevention to ensure adequate protection.

There are many preventative treatment options, ranging from pills or topical products to flea and tick collars to yearly injections. Your veterinarian can help you find the right option. In general, preventative treatment is much safer and less invasive than treating your pet for insect-borne diseases, but if your pet has underlying health issues be sure to discuss this with your veterinarian.

Pets who spend a lot of time outdoors or live in high-risk areas are more likely to contract an insect-borne disease. Companion Animal Parasite Council maps show disease prevalence by state and county.

While it is important to search for and remove ticks from your pet during the summer high season, this should not replace preventative tick therapies. Nymphal or immature ticks can spread Lyme disease and, at about one millimeter in size (similar to a poppy seed), they are difficult to see with the naked eye.

Finally, we recommend your pet be screened for insect-transmitted diseases every year or two, depending on your prevention method and your pet’s lifestyle. This will ensure any underlying disease is diagnosed and treated sooner rather than later. If your pet displays symptoms such as coughing, difficulty breathing, lethargy, or joint pain, see your veterinarian, as these can be symptoms of an insect-borne disease.

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This article appears in the spring 2022 issue of On Call magazine.

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