We’ve been seeing a lot of pets come in recently with small, red bug bites on them. Some are very itchy, others are not. Many people are concerned they are tick bites, but they are actually bites from a biting fly. The scientific name is Culicoides species, but the fly goes by many common names such as the biting midges, midgies, no see-ums, or punkies.



Red, circle rashes are commonly seen on the areas where hair is thinnest such as the abdomen or groin area.

In the U.S., the Culicoides species are primarily a nuisance and the major medical issue is allergic reactions to the bites. They are responsible for transmitting a virus in sheep and cattle. Some horses experience allergic reactions to the bites, resulting in equine allergic dermatitis, affecting the withers, mane, tail and ears of the horse. Other species found in other parts of the world such as Africa and South America can transmit more serious diseases.


When & Where:

They can be seen during early morning and evenings, and even during the daytime on cloudy days when winds are calm. There are over 4,000 different species of in the Ceratopogonidae family, and over 1,000 in just one genus, Culicoides. The distribution of the genus Culicoides is world-wide. The natural habitats can vary by species. Marshy areas are major producers of many species. Additional sources for some species include highly organic soil that is wet but not underwater such as those found with high manure loads from swine, sheep and cattle. Larvae can be found in a damp location, such as under bark, in rotten wood, compost, mud, stream margins, tree holes, or water-holding plants. These insects do not establish inside homes, apartments, or inside animals.

The adults are gray in color and less than 1/8 inch long or about the size of the tip of a lead pencil. The two wings can have hairs and color patterns. The mouthparts are well-developed for biting and blood-sucking in females, but not in males, so the females are the ones who bite. Adult females may show a red (blood-filled) abdomen.



Treatment usually consists of managing the secondary problems from the rash. The itching can be diminished by using oral Benadryl (diphenhydramine) at a dosage of about 1 mg per pound of body weight. Topical antihistamines such as hydrocortisone can also be used as long as the pet can’t lick it off. If the pet scratches too much and irritates the skin a secondary bacterial infection could result.


Management and Prevention:

In the past, management included draining marshlands and using the insecticide DDT, which had negative impacts on the environment and were not efficient. Currently, on a large scale, removal trapping is conducted using carbon dioxide to lure them to an insecticide-treated target where they are killed.

Homeowners can install proper screens on windows and patios although most Culicoides can pass through 16-mesh insect wire screen and netting, so a smaller mesh size is required. Since they are so small and are weak fliers, ceiling and window fans can be used at high speeds to keep them out of small areas.

For humans, repellents containing DEET (N,N-diethyl-meta-toluamide) typically used as mosquito repellents are also labeled for use against them and can be applied prior to exposure. It is important to read and follow the directions for application that are printed on the label.

For pets, a pyrethrin based topical ointment or spray can be used in specific spots where the pet is being bitten. A flea & tick repellent such as Vectra can be applied topically. We carry all of these products at Bemidji Veterinary Hospital. Avoid tall grasses and marshy areas especially at dawn and dusk.


If you have any questions regarding these bug bites or suspect your pet is having secondary problems related to them, feel free to call us at 751-2753.