Washington has over 40 species of mosquitoes. Some, like Culex tarsalis, can spread mosquito-borne diseases such as West Nile virus. To prevent mosquito bites, wear long-sleeved shirts and pants, make sure doors and windows are screened, and avoid mosquito-infested areas or stay indoors when mosquitoes are most active from dusk to dawn. When outside in mosquito-infested areas, use an effective repellent that contains the active ingredient of DEET, Picaridin, oil of lemon eucalyptus, PMD, or IR3535.

Photo: James Gathany, CDC

The first step in avoiding mosquito bites is not allowing them to reproduce around your home. Standing water in artificial containers such as buckets, tires, and wading pools make great mosquito nurseries. These Culex mosquito larvae are resting and breathing at the surface of the water. A single pupae, which will soon become a flying adult, is in the center. When the stagnant water is disturbed they'll twist and tumble downwards. Under ideal conditions, mosquito larvae can become biting adults within a week, so it's important to routinely empty sources of standing water around the home during warmer months.

Photo: James Gathany, CDC

Ticks are small blood-feeding parasites that can transmit diseases like Lyme disease and tick-borne relapsing fever. Some types of ticks perch on the edge of low-lying vegetation, such as this Ixodes pacificus, and grab onto animals and people as they brush past. Other types of ticks are associated with rodents and their nests.

Avoid tick bites in wooded, brushy, or grassy places by wearing light colored long pants and shirts - makes the ticks easier to see. Tuck pants into socks and shirts into pants. Use an effective tick repellent. Check youself, children, and pets thouroughly after being in tick habitat. Keep rodents out of homes and cabins to avoid the types of ticks that come out at night to feed.

Photo: James Gathany, CDC

Black widow spiders are common in eastern Washington and there are a few small populations of them on the western side of the state. Black widows are usually associated with undisturbed piles of wood, outbuildings, rock piles, bales of hay, crawl spaces, and other dry dark holes. This black widow has caught two paper wasps. Her distinct red markings under her belly are clearly visible - these markings often look like an hourglass.

Like most spiders, black widows are shy and bite only reluctantly, usually when they are pressed against our skin or provoked. But unlike most spiders in Washington, black widows are highly venomous. Wearing gloves when working around potential black widow habitat can help prevent bites. Sealing gaps around windows and doors will help keep spiders out. If someone is bitten by a suspected black widow or develops what appears to be an allergic reaction to any other spider bite, seek medical attention.

Photo: iNaturalist, © 2008, Used with permission.

Deer flies and horse flies are well known for buzzing relentlessly around their target, landing stealthily on exposed skin, and delivering a painful bite. The bite can itch for days and scratching may lead to infection. These flies are active during the day and are especially common around ponds, streams, marshes, and lakes. They are capable of transmitting tularemia, a bacterial disease they can pick up from wild animals. To avoid bites, cover exposed skin by wearing long sleeved shirts and pants. Some insect repellents are effective at keeping these flies from biting. If you're bitten, wash the bite area with soap and water, apply a bactericide, and use an anti-itching ointment.

Photo: Lynette Schimming, © 2008, Used with permission.

Yellow jackets and wasps are considered beneficial insects because they feed upon other insect pests. A few species, such as these western yellow jackets, scavenge for meat and sweets and can become pests themselves, especially at picnics and campgrounds. Don't attract yellow jackets by wearing brightly colored clothing, perfumes, or other strong scents. Keep food covered or behind screens when eating outdoors. Dispose of food properly, including decaying fruit in the late summer. Avoid swatting at individuals or disturbing their nest - this will only agitate the yellow jackets or wasps and make them more likely to defend themselves by stinging perceived threats.

Photo: Whitney Cranshaw, Colorado State University, Bugwood.org, Used with permission.

Bees play an important role in pollinating flowering plants. It is estimated that one third of the human food supply depends on insect pollination, most of which is done by bees. Although a bee sting can be deadly to those with allergies, virtually all bee species are non-aggressive if undisturbed. But like wasps and yellow jackets, bees will defend their nests from perceived threats.

If someone is stung by a bee, quickly remove the stinger if still present by scraping a straight-edged object, such as a credit card, across the stinger. Wash the sting site. Apply ice on and off for 10 minute periods. If necessary, take an antihistamine or apply creams to reduce itching. Call 911 if a person has a severe reaction, such as trouble breathing, swelling anywhere on the face or in the mouth, throat tightness, feeling week, or turning blue. Those with severe allergies should wear a medical ID bracelet and keep an emergency epinephrine kit with them.

Photo: iNaturalist, © 2008, Used with permission.

The hobo spider, Tegenaria agrestis, is a common funnel web weaving spider. Hobo spiders can be found around home foundations, and beneath rocks, wood, and ornaments in the yard. Their bites can produce skin injuries or lesions that are sometimes misidentified as the bite of a brown recluse (which doesn't live in Washington). Hobo spiders are often confused with the giant house spider, which are commonly found in and around homes.

Hobo spider bites typically occur when they are squeezed, such as when someone picks up a piece of fire wood or puts on clothing where the spider is hiding. Wear gloves when working around potential hobo spider habitat. Screen windows, plug gaps around doors, and check firewood before it's brought inside to help keep spiders out. If someone is bitten by a suspected hobo spider or develops what appears to be an allergic reaction to any other spider bite, seek medical attention.

Photo: Whitney Cranshaw, Colorado State University, Bugwood.org, Used with permission.

Fleas can cause great discomfort to our pets and leave us with small itchy bites, often on our legs. Their bites can cause allergic reactions and scratching can lead to infection. Fleas are capable of picking up plague from wild rodents and transmitting the bacterial disease to people. To help prevent flea infestations, keep lawns trimmed and avoid piling sand and gravel for long periods around the home. Vacuum carpet and furniture. Clean pet and people bedding regularly. Practice rodent control around the home. Use flea control for your pets - talk to your veterinarian about the most effective options. Keep pets away from wild animals. Flea control is best achieved with a simultaneous, coordinated effort that includes target cleaning, pet treatment, and home treatment.

Photo: Peter J. Bryant, © 2007, Used with permission.

Bed bugs are small, brownish, flat insects that often feed on people while they're sleeping. This bed bug has been feeding for five minutes and its belly is beginning to swell with blood. Bed bugs don't spread disease but their bites can cause itchy red welts. Scratching the bites can lead to an infection. During the day, bed bugs often cluster in crevices of the bed mattress, box spring, and bed frame. They can also be found in cracks along walls and floors and in and under other furniture. Signs of a bed bug infestation include itchy bites noticed after sleeping, and small rusty-red and black spots on the mattress, pillows, and bed linens. The first step in dealing with a bed bug problem is confirming the infestation by identifying the bugs. Contact a pest control company that has experience in controlling bed bugs.

Photo: Whitney Cranshaw, Colorado State University, Bugwood.org, Used with permission.