New research indicates that bed bug faeces contain high levels of histamines and that they can be long lasting in homes with a history of bed bug infestations.
Bed bugs are a nuisance pest. They’re seen as disgusting and their bites while itchy, aren’t really considered of significant medical importance. However, recent studies on bed bug histamines suggests a re-think. Histamines in humans are released within the body as part of the immune response.
They cause inflammation, allowing other components of the immune system to do their work. However, they can also be released in response to allergens which may be inhaled or land on the skin, causing respiratory problems or skin rashes. Some foods are also high in histamines such as fermented food and alcohol (especially red wine) and can trigger this inflammation response. It turns out that bed bug faeces are also high in histamines.
A study from North Carolina State University has found that histamine levels in bed bug infested homes were 20 times higher than the histamine levels in homes with no history of bed bugs. What’s more, the histamine levels in bed bug infested homes did not reduce significantly when tested three months after insecticide and heat treatments were used.
With the histamines concentrated in the bedrooms, generally the centre of a bed bug infestation, inhabitants would be exposed to high levels of histamines over a prolonged period. Whether the histamine levels are high enough to cause allergic responses and health problems will be the subject of future research.
DeVries, Z., Santangelo, R., Barbarin A. and Schal, C. (2018). Histamine as an emergent indoor contaminant: Accumulation and persistence in bed bug infested homes. PloS One, 13(2).