Good Night, Sleep Tight… A beany, bed-bug delight

Did you sleep well last night? You would not have felt so cosy if your mattress had been infested with bed bugs (Cimex lectularius), an ancient pest that is making a comeback in the modern world, complete with pesticide resistence. Looking for a new solution to this age-old problem, scientists from the Universities of California and Kentucky took their inspiration from reports written in the first half of the twentieth century (sadly not available online) that describe the use of bean leaves (in Eastern Europe) to trap bed bugs so that they can then be destroyed.

The reason that those reports are only now being taken seriously is that for more than 50 years, bed bugs haven’t been a problem for the majority of people living in the Western world. Since the Second World War, we have been dealing with infestations with pesticides, and we had been winning the bed bug war. But now they are appearing again in the US and the UK, and no one is entirely sure why the tide seems to be turning in their favour.

Bed bugs have plagued humanity since history began, and it’s thought that they evolved to parasitize bats before moving on to humans. When we were hunter-gatherers and roving herdsmen, we presented a moving target – there were no beds to house bugs. But it has been a different story since we started moving in to cities, and since we developed a taste for heating our homes in the winter that allows bed bugs to breed all year round.

And so intrepid researchers have been trying to find out exactly how bean leaves trap bed bugs, which involves collecting bean leaves, forcing bed bugs to wander over them and tracking how long it takes them to get stuck. Once they have got stuck, videography and scanning electron microscopy allows us to