How did bedbugs make a comeback?

SDSTAFF Doug replies:

Recently in the U.S. we’ve seen the resurgence of two pests that were, for many years, getting by almost entirely under the radar: bedbugs (Cimex lectularius) and lice (Pediculus humanus et al). The reasons behind the resurgence are a little murky, but there’s a fundamental factor at work here that’s hard for some people to accept: our cultural practices have changed over the last generation or two, and the things people used to do, and know, regarding these pests, have fallen out of our collective awareness — and all the while, the critters were effectively waiting for us to let our guard down.

Back around the start of World War II, people dealt with bedbugs and lice all the time. The use of DDT — which is, contrary to popular perception, a remarkably safe pesticide when used in small amounts in people’s homes rather than released in huge quantities into the environment — was a big part of our temporary success against these pests. But there were also cultural practices which folks then took for granted, but persist today only in words and phrases whose original senses have been lost: “Sleep tight, don’t let the bedbugs bite” was a reference to the once-standard practice of changing one’s bed sheets every day and tucking them in tightly, a simple but effective way of keeping bedbugs out; the terms “nitpicking” and “cootie shots” both related to the control of head lice. Modern parents generally do not check their kids’ hair regularly for nits, nor do they change the sheets and check under the mattress every day — so the return of bedbugs and lice is not really a big surprise.

Matters are made worse because we now have a generation of people who didn’t grow up with bedbugs and lice, whose “knowledge” about them consists of little more than myths and rumors, and who frequently are unwilling to abandon these beliefs — e.g. that such pests are a sign of filth, or associated with poverty. These animals are hitchhikers, and can ride from a conventionally clean home to an obviously dirty one just as easily as the other way around. Practically any home can harbor both bedbugs and lice, in large numbers, because the normal routines of home cleanliness aren’t sufficient to control them: head lice hide in children’s hair, and bedbugs take cover under mattresses, behind pictures, in crevices in walls or furniture, behind wallpaper or paneling, or under carpeting. Information about spotting signs of these pests and the proper ways to control them is readily available in many places online. (One of the all-time best sources of guidance like this is the University of Florida’s Featured Creatures site. Authoritative and useful articles on bedbugs can be found here and here; good louse info is here, here, and here.)

But re-educating people about bedbugs and lice is going to be a drawn-out and difficult process as long as there are people who say “It can’t possibly be my kids or my home that’s the problem, because I keep things spotless!” Households where an infestation exists but is ignored or actively denied because it’s largely out of sight will serve as a refuge for pests, which will then reinfest other people’s kids and homes no matter how good everyone else is at control. (This combination of lack of awareness and denial is also a major reason that little is known about regional abundances of bedbugs. Since bedbugs occur exclusively in human dwellings, our knowledge of their whereabouts is limited by what people actually report — and clearly a lot of people have bedbugs in their homes and either don’t know it or don’t tell anyone about it. Bedbugs occur everywhere, we know, but we don’t reliably know whether some parts of the country have significantly more.) Management of these pests can only be truly effective if everyone follows the same practices and accepts their responsibility as part of a community. In the immortal words of Walt Kelly: “We have met the enemy, and he is us.”

SDSTAFF Doug

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