The Brown Marmorated Stink Bug (Halyomorpha halys) is the species most commonly encountered as a home invader, particularly during cooler months when they seek shelter indoors. This insect, originally from East Asia, has become a widespread nuisance pest across the United States. While their presence is unwelcome and their odor is unpleasant, the overall danger they pose to human health is generally low. Stink bugs do not possess venom and do not actively seek to cause physical harm. The primary concerns stem from the defensive chemicals they release and the potential for allergic reactions in sensitive individuals.
Addressing Physical Harm: Do Stink Bugs Bite or Sting?
Stink bugs are not equipped with stingers and cannot sting a person. Furthermore, they do not bite humans in a defensive or aggressive manner.
These insects are phytophagous, meaning their diet consists exclusively of plants. Their mouthparts are a specialized structure known as a rostrum, designed for piercing plant tissue and sucking out internal juices. Since they do not feed on blood, they lack the motivation of pests like mosquitoes or ticks to bite humans.
Health Effects from Defensive Odor and Secretions
The main health concern arises from the foul-smelling chemical cocktail that stink bugs release when disturbed, threatened, or crushed. This secretion is produced by scent glands on the abdomen and thorax and acts as a defense mechanism. The characteristic odor is caused by aldehydes, specifically trans-2-octenal and trans-2-decenal.
Direct contact with this defensive liquid can cause skin irritation, often resulting in temporary contact dermatitis. If the secretion contacts the eyes, it may lead to irritation or conjunctivitis. Washing the affected area immediately with soap and water is recommended to minimize irritation.
Accidental ingestion of a stink bug, such as one hidden in fresh produce, is not poisonous, but the strong chemicals can still cause temporary discomfort. The digestive system may react to the potent aldehydes, leading to symptoms like nausea, upset stomach, or localized irritation of the mouth and throat.
Assessing Indirect Health Risks
While stink bugs do not transmit human pathogens, they can pose an indirect health risk to individuals with pre-existing sensitivities. Allergic reactions are a secondary concern, triggered by proteins found in the insect’s body, including shed exoskeletons, dried feces, or aerosolized defensive secretions.
These airborne particles can act as allergens, similar to dust mites or cockroaches, especially when large numbers aggregate indoors during overwintering. Exposure to these aeroallergens may trigger symptoms of allergic rhinitis, such as a runny nose and sneezing, or cause eye symptoms like tearing and itching. For people who suffer from asthma, inhaling these irritants can exacerbate the condition, leading to coughing, wheezing, or shortness of breath.