Bed bugs hide during the day and wander at night to feed on the blood of nearby sleeping humans. The inconspicuous habits make bed bugs difficult to detect and that in turn makes their control problematic. Bed bug control would be enhanced with accurate and effective detection at the earliest stages of infestation. A number of bed bug detection methods are currently used including bed bug sniffing dogs, tiny wasps that respond to bed bug odor and a variety of traps. Traps would be more effective if we knew what attracted bed bugs. Some attractants are known. Carbon dioxide, released when we exhale, is known to attract bed bugs and can increase effectiveness of some types of traps. However, carbon dioxide is difficult to manage in a trap. Bed bugs also respond to body heat and a heated trap can be more effective than an unheated one. Do humans produce odors that could be used to lure bed bugs into a trap?
Odor will attract some insects, such as male moths, from considerable distances and are effective for detecting moth species. Entomologists would love to be able to trap all insects as easily as male moths, but that goal has not been achieved and is probably not practical. Some insects are not reliant on odors for finding resources, so an odor based trap is not possible.
Bed bugs are not very reliant on odor for orientation. Bed bugs do have a pheromone, but it is marginally effective in bed bug traps. A group of Swedish scientists recently collected odors from human volunteers, and tested the ability of bed bugs to detect and respond to the odors. The volunteers were required to shower with a non-perfumed soap 24 h prior to the odor collection and refrain from eating foods that are known to contain chemicals that are released as odors through the skin (such as garlic). The collection device, a giant odor proof plastic bag, was created by heat sealing together, multiple commercially available plastic turkey roasting bags. Volunteers were required to strip naked and be sealed in the bags for 150 minutes with only the head protruding.
About 100 volatile odor chemicals were collected and tested. Bed bugs odor receptors responded to only 5 of these chemicals. The 5 chemicals were tested for attractiveness and failed to attract bed bugs. The conclusion is that bed bugs are not using their sense of smell, other than carbon dioxide detection to locate their human hosts. Other factors such as heat (or infrared detection) may be more important to locating a host. This research suggests that a better bed bug detection system must involve traps that work by means other than odorous attraction.