Bed bugs are small, parasitic insects that feed on the blood of humans and animals. Adult bed bugs are flat, oval-shaped, and about the size of an apple seed, making them difficult to spot. Their secretive nature and ability to hide in tiny crevices make the possibility of them moving through bedding a common concern during an infestation. Understanding how these creatures interact with linens clarifies their movement toward a sleeping host.
The Truth About Fabric Penetration
Bed bugs generally cannot physically crawl through the woven fibers of a standard bed sheet. The limiting factor is their size, even at the earliest stage of their life cycle. A newly hatched bed bug, known as a first-instar nymph, measures approximately 1.5 millimeters in length.
The tight weave of modern sheets, especially those with a moderate to high thread count, creates a barrier too dense for even the smallest nymphs to push through. The spaces between the threads are significantly smaller than the width of the nymph’s body. This barrier is only effective if the fabric is undamaged and the weave is tight. Loosely woven materials, such as some knit blankets, may have gaps large enough for the smallest nymphs to potentially pass through.
How Bed Bugs Navigate Bedding Surfaces
Bed bugs easily use sheets as a pathway to reach a host, as they rely solely on crawling. The insects are attracted to the carbon dioxide and heat a sleeping person emits. This guides them from their hiding places in the mattress or bed frame toward the top of the sheets.
Bed bugs possess tiny claws that allow them to grip and climb textured surfaces effectively. The rough texture of common bedding materials, such as cotton or flannel, provides the necessary friction for movement. This is in contrast to slick surfaces like glass, which they struggle to climb. The sheet acts as the final bridge from their harborages to the exposed skin of the person in bed.
Using Bedding as a Barrier
Since bed bugs use the surface of bedding as a route, certain types of bedding are used for non-chemical control. Specialized encasements designed for mattresses and box springs are an important part of managing an infestation. These encasements feature specialized zippers and impermeable fabric to prevent bed bugs from entering or escaping.
The encasement fabric traps any existing bed bugs inside to starve them. For this strategy to work, the encasement must remain on the mattress for 12 to 18 months, as bed bugs can survive for long periods without a blood meal. Regular sheets and other washable bedding should be laundered frequently using high heat to kill any bugs or eggs resting on the surface. Washing at temperatures of 140°F or higher, followed by a high-heat drying cycle, is necessary to eliminate all life stages.