When you discover a bed bug and squish it, the sight of a red stain can be unsettling. This often leads to questions about what that red liquid is and why it appears. Understanding this phenomenon provides insight into bed bug biology and behavior.
The Nature of the Stain
The red liquid that appears when a bed bug is squished is blood. This is not the bed bug’s own blood. Insects, including bed bugs, possess hemolymph, a clear or yellowish fluid that transports nutrients but does not carry oxygen. The red color comes from the blood of the host the bed bug recently fed upon.
Bed bugs consume large blood meals. When engorged, their bodies swell. Squishing them expels the ingested blood meal, explaining the noticeable red stain, especially after a recent feeding.
Why Bed Bugs Carry Blood
Bed bugs are obligate hematophagous insects, meaning they must feed on blood to survive. Both male and female bed bugs, along with their immature stages (nymphs), require blood to develop.
These insects feed every 3 to 10 days. During feeding, a bed bug pierces the host’s skin with specialized mouthparts, injecting an anesthetic and anticoagulant to feed unnoticed. A single feeding can last between 3 to 12 minutes, allowing the bed bug to become fully engorged.
What a Bloody Stain Indicates
Finding a bloody stain from a squished bed bug indicates recent feeding activity and confirms bed bug presence. These stains, ranging from bright red to rusty or dark brown, are often found on bed sheets, mattresses, or other bedding. The stain’s color and freshness offer clues about the blood meal’s recency. A bright red stain suggests a very recent feeding, while darker, rust-colored spots indicate older, partially digested blood or fecal matter.
These discoveries are a key sign of an active bed bug infestation. Other signs include dark, ink-like fecal spots (digested blood) on surfaces, shed skins (exoskeletons) from growing nymphs, and tiny, pearl-white eggs. An unusual musty odor, sometimes described as sweet or like cilantro, can also indicate a larger infestation.
Next Steps After Finding a Squished Bed Bug
Discovering a squished bed bug with a blood stain should prompt immediate action to assess a potential infestation. First, confirm identification; if possible, save the specimen in a sealed bag for professional verification. While bites can suggest bed bugs, they are not a reliable indicator due to variable reactions. Focus instead on finding physical evidence.
Thoroughly inspect the surrounding area. Common hiding spots include mattress seams, box springs, bed frames, and headboards. Expand the search to nearby furniture, wall cracks, baseboards, and electrical outlets. Look for signs like dark fecal spots and translucent, empty shed skins.
Professional pest control is generally recommended for effective eradication. Do-it-yourself methods often fail to reach all hidden bed bugs and their eggs, leading to re-infestations. Professional exterminators possess the expertise, specialized equipment, and treatments, including heat or chemical applications, to target bed bugs at all life stages. They provide a comprehensive plan, including follow-up visits, to ensure complete elimination and prevent future problems.