Complete Guide To Identifying A Bug Bite In The NW

August 10, 2022
yellow jacket bite

Bug bites can be annoying, worrisome, and sometimes painful. No one likes to get bit by bugs but it does happen from time to time. However, sometimes they can be challenging to identify as they leave similar bite marks. Identifying a bug bit not only helps you identify the bug that bit you but also helps you to know how to treat the bite as well. Listed below is an easy guide to identifying a bug bit in the NW. 


Carpenter And Moisture Ants

The most common ants in Oregon and Washington are moisture ants, carpenter ants, and odorous ants. Odorous ants do not bite whereas carpenter ants and moisture ants can bite if they feel threatened. When they feel the need to defend themselves they will bite with their jaws and pinchers or their stingers. As this happens they release a chemical called formic acid into the skin which some people are allergic to.  

Ants belong to the Formicidae family and range in size. They are typically black, brown, or red in color and have segmented bodies consisting of a head, thorax, and abdomen connected by a narrow waist. They have six legs and two antennae. Most of the time ants are found outside but they can make their way inside when searching for food and shelter becoming an inconvenient nuisance to homeowners. 

carpenter ant bite

The American And German Cockroach

There are four different kinds of cockroaches that live within the Pacific Northwest. Of the four different types, only two have been known to bite humans which are the German cockroach and American cockroach. 

Typically cockroaches will leave humans alone but if an infestation gets bad enough and they no longer have a thriving food source they have been known to bite humans. The most serious case of cockroaches biting humans was on seafaring ships where cockroaches depleted their food source and started eating the skin and nails of those on board. 

Cockroach bites are similar to bed bugs and mosquito bites but are larger in size. They are bright red in color, itchy, and look like raised bumps on the skin. 

cockroach bites

Common Spiders

There are over 20 types of spiders identified in the states of Oregon and Washington. However, not all of them are commonly seen by humans on a consistent basis. Here we will address the most common spiders known to live close by and in people’s homes. 

The Common House Spider– This spider is the most common spider to be seen living indoors. You will know if this type of spider is living within your home because of the webs it leaves in the corners of your room. A common house spider will most likely leave a small, red, itchy bump accompanied by a little swelling

The Hobo Spider– Contrary to popular belief, these spiders are mostly harmless. A bite from one of these spiders will induce some redness, mild pain, and maybe some swelling. You will also most likely see them outside of your home as they live in woodpiles and around retaining walls. 

The Wolf Spider– This spider bite looks like many of the other spider bites. A red, itchy, swollen bump that usually goes away within a few days. Some people do, however, have an allergic reaction to these bites increasing the size of the bite and possibly leaving a red line that extends from the bite mark. 

The Western Black Widow– Compared to the other spiders listed, this spider is venomous and can be dangerous to small children, the elderly, and those who have high blood pressure. Signs that you’ve been bit by one of these spiders are small red marks with swelling followed by more pain as time passes. It may induce stomach cramping, sweating, and in serious cases trouble with breathing. 

To learn more, read one of our previous articles on how to treat a spider bite  and signs you’ve been bitten by a spider.

black widow bite

@Davido flickr

Bed Bugs

These nasty pests can be found in homes and hotels anywhere in Oregon and Washington. They can be found in clean spaces or dirty spaces and are known to hitch rides with those who travel. Once they have found their way into your sleeping quarters they are difficult to get rid of so it’s important to know what to look for when it comes to signs that you have bed bugs. 

Bed bug bites look similar to most insect bites except they have a feeding pattern of breakfast, lunch, and dinner that resembles a zig-zag pattern where they bite. Their bites are very itchy and will most likely appear red in color anywhere on the body. 

bed bug bite

@Magalie flickr


The most common wasps that people run into in Oregon and Washington are yellowjackets and paper wasps. The problem with these wasps is that they can sting over and over causing it to be a very painful experience. Wasp stings are venomous so you will know when you have been bitten. Symptoms include pain, redness, burning, swelling, and itching that is localized. Wasp stings are also the stings most likely to trigger an allergic reaction. About 2 million Americans are allergic to the venom of stinging insects. A sign of of an allergic reaction can result in redness and swelling that extends beyond the sting site. The swelling may extend about 4 inches from the sting site over a period of a couple of days. A more serious reaction is a systemic allergic reaction known as anaphylaxis. Symptons can include a diffulty breathing, hives, rapid pulse, and dizziness. This condition requires immediate medical attention. The good news when it comes to wasps is that if you leave them alone it is unlikely that you will get stung. 

wasp sting



This year in the Portland Oregon and Vancouver Washington area mosquitos have been at an all-time high for increased populations, especially near areas of water. Though mosquitos are common throughout the spring and summer it’s not enjoyable to be outside when you feel like you’re being attacked by these pests. If you do get bit by a mosquito you will notice that a puffy, reddish bump appears within minutes of the bite. This bump can become hard over time and very itchy. They can even turn into small blisters or dark spots that look similar to bruises. If you have an impaired immune system, you may experience a more severe reaction such as hives. Why does it itch? Mosquitos inject saliva into your body while siphoning your blood. Their saliva contains an anticoagulant and proteins that most people are allergic to and triggers your body’s immune system.  Your immune system then releases histamine, a compound that helps white blood cells get to the affected area. Histamine is what causes the itchiness, inflammation, and swelling.


Since insect bites can look very similar it’s important to pay attention to your surroundings. If you know the insect that bit you then you will be able to take care of it before it causes problems. If you do not know what bit you then we suggest a little research along with some investigation around the area you were bitten. You can also learn more about some common pest allergies in one of our previous articles. Whether you are able to discover the source or not, our local pest control technicians can help with preventing further bug bites in or around your living spaces. 


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