Why bites are a bad test
The Washington Department of Health: “Bed bug bites can take up to two weeks to produce a reaction. Some people may have no reaction at all.” One partner covered in welts and the other untouched is common and proves nothing about who is being bitten. Bites also look like other things. Look for the bugs and their traces instead.
What to look for
- Live bugs: flat, oval, apple-seed sized and reddish-brown when fed; nymphs are smaller and paler
- Dark fecal spots that bleed into fabric like a marker dot, along mattress seams and box-spring edges
- Shed skins and tiny pale eggs in seams, screw holes, behind headboards
- Rust-colored smears on sheets
- A sweet, musty odor in heavy infestations
Where
Within a few feet of where people sleep or sit for long periods: mattress seams and tags, the box-spring frame and its underside, the bed frame’s joints, the headboard, nightstands, the sofa where someone naps. Later, baseboards and outlet covers. They do not need a dirty home; they need a host and a crack.
The biology that makes them hard
WSU Extension’s fact sheet: “Under ideal conditions, bed bugs can complete their life cycle from egg to adult in as little as 35 days, and they may reproduce 3 to 4 generations per year,” and an adult “can live up to 10 months and can survive several months without feeding.” That is why an empty unit does not fix itself and why a one-time spray that misses eggs comes back in a month.
What to do with a suspect
Catch it with clear tape onto white paper — the local health department gives schools the same advice — and send us a photo. Identification is free and keeps you from paying to heat-treat a carpet beetle.