If you have a cluster of bites, it’s particularly likely that you have bed begs. “One of the most tell-tale signs that you’ve been bit by a bed bug is having a group of bites clustered or in a lined path on an area of your body that has had direct contact with your mattress while sleeping,” says pest expert Zack DeAngelis. “Bed bugs usually don’t leave one single bite and often leave multiple in clusters.“ae0fcc31ae342fd3a1346ebb1f342fcb To find out the tell-tale mark of another insect, beware that If You See This in Your Yard, Prepare for a Bug Invasion, USDA Says. Of course, there are exceptions to every rule and not all bed bugs bite in clusters. So if you see a single bite, it could still be from a bed bug. People have a variety of reactions to bed bug bites, but something that tends to be common across the board is that bed bug bites are often red and swollen. “Depending on the sensitivity of an individual, bed bug bites can range from a small red bump to an inflamed itchy red bump,” says entomologist and pest control manager Mike Duncan. To see which scary bug warrants a call to officials, check out If You See This Terrifying Insect, Call the Authorities Immediately. Unlike mosquito and flea bites that only last for a few days, the evidence of bed bug bites lingers for longer. “Bed bug bites can take up to two weeks to heal; it will vary based on how severe the bites are,” explains DeAngelis. He also notes that if you have bed bugs, the bites will likely keep coming, which will make your skin irritated for a longer time. And for more up-to-date tips and tricks delivered straight to your inbox, sign up for our daily newsletter. Itching is a common response to bed bug bites. “More than likely, after being bit by a bed bug, people will feel a strong source of discomfort and itchiness at the source of the bites,” says DeAngelis. “However, the degree of itchiness and discomfort will vary, as it depends on that individual’s immune response.” It’s important to note that if you got the bite in the middle of the night, the itching may subside by the time you wake up—so a non-itchy bite could be from a bed bug, too. To see if you have an even bigger bug problem, check out If Your House Smells Like This, You May Have a Bug Problem.