Some bed bugs are better at getting between your sheets than others, reveals new research.
The study suggests many leading traps used by pest management firms are ineffective at getting rid of the little critters.
Researchers found that tropical bed bugs are better able to use small pads on their legs to grip the surface of the trap and scale the inner wall.
The study, published in the Journal of Economic Entomology, has shown that the tropical bed bug, Cimex hemipterus, can readily climb out of smooth-walled pitfall traps.
The researchers tested four leading traps, all designed in the US, where the bed bug Cimex lectularius is more common.
The traps were effective at trapping adult C. lectularius but not adult C. hemipterus.
The C. hemipterus bugs were better at using the small pads on their legs to climb things.
Taking a close look using a scanning electron microscope, the Malaysian researchers found that the tibial pad of adult C. hemipterus bed bugs showed the presence of a greater number of hairs than on that of C. lectularius.
They also had a more well-developed organ for glandular secretion at the base of the hairs.
The researchers saw the bed bugs using the tibial pad while climbing on the smooth surfaces.
However they say further study is needed to understand exactly how the enhanced hairs and glands in the tibial pads enable C. hemipterus to grip a smooth vertical surface.
In 2014, genetic tests revealed that a single undetected pregnant bed bug is all it takes to start an entire infestation.
One pregnant bug could rapidly create a colony of thousands that feed on humans.
Bed bugs are capable of surviving without feeding for a month as they wait for a human.
Study co-author Professor Chow-Yang Lee, of Universiti Sains Malaysia, said, regardless of how tropical bed bugs do it, their ability to escape pitfall traps 'has profound implications in the monitoring and potential management of bed bug infestations.'
C. lectularius is mainly found in temperate regions, and C. hemipterus is found primarily in tropical regions.
However they often co-exist in regions such as Africa, Australia, Florida, Japan, Taiwan, and southern China.
'Unfortunately, due to their close resemblance, most pest management professionals are unable to tell between C. lectularius and C. hemipterus' said Dr Lee.
'Hence, if some of the pitfall traps used in this study, which otherwise could effectively contain C. lectularius, were used during the monitoring process, they would not be able to contain C. hemipterus, which may give a false impression that the monitored premises are free of bed bugs or having a low infestation rate.
'This may affect the decision-making process on the treatment type, and eventually lead to control failure.'