How to tell if you have bed bugs
Most people who discover bed bugs do not see the insect first. They see the traces. Four signs that come before a sighting, and all of them you can check tonight.
Bed bugs are exceptional at hiding. Their bodies are flat enough to slide into a gap the thickness of a sheet of paper, and they come out only at night and only briefly. Weeks often pass between an infestation starting and anyone seeing a single insect.
Sign one: bites in a line or a cluster
Bites usually appear on skin left uncovered during sleep: arms, shoulders, neck, legs. What identifies them is not the shape of the bite but the arrangement: three or four in a line or a small group, because the insect feeds, moves a little, and feeds again.
One important caveat. Reactions vary enormously between people. One person can wake up covered in visible bites while whoever sleeps beside them shows nothing at all. No bites on one person does not rule out an infestation.
Sign two: dark spots on the bedding
Look for small dark brown or black dots on the sheet or along the mattress edge, about the size of a pen tip. This is faeces, and because it soaks into fabric it spreads slightly at the edges, unlike a dried spot of ink.
If you find those dots clustered along a mattress seam, you are not testing a possibility any more. You are looking at a harbourage.
Sign three: shed skins
Bed bugs moult several times before adulthood, leaving behind a translucent amber shell shaped exactly like the insect but empty. Finding these means the infestation is not new and the population is breeding in place rather than having arrived yesterday.
Sign four: exactly where to look
A proper check takes ten minutes with a torch, and works outward from wherever the sleeper is closest to:
- Mattress seams and edges, especially the corners and the piping.
- The inside of the bed frame, its joints, and underneath the base.
- Behind the headboard and in the gap between it and the wall.
- Nearby sofas, cushion seams, and the carpet edge against the skirting.
What not to do
Three common reactions all make the problem harder:
- Moving the mattress to another room. This moves the infestation with it and turns one room into two.
- Spraying a general insecticide from a shop. It scatters them into deeper and more distant cracks, which makes proper treatment harder later.
- Throwing the bed out immediately. Expensive, usually unnecessary, and it solves nothing if they have already reached the surrounding furniture.
Why this pest needs follow-up more than most
Bed bug eggs are tiny and cemented into cracks, and surface treatment does not reach them any more than it reaches a cockroach egg case. Treating bed bugs in a single visit is therefore incomplete by nature, and is finished with a second visit once the remainder has hatched.