Body lice are tiny insects that live primarily in clothing and bedding, feeding on human blood. These parasites are distinct from head lice, which infest the scalp, and pubic lice, found in coarse body hair. Understanding the visual cues of body lice on skin is important for identifying an infestation.
What Body Lice Look Like
Adult body lice are small, measuring 2.5 to 3.5 millimeters in length, which is comparable to a sesame seed. Their bodies are flat and oval-shaped, appearing tan to grayish-white. After feeding on blood, they may take on a reddish-brown color. They have six legs with claws, allowing them to cling to clothing fibers or hair.
Immature lice, known as nymphs, resemble smaller versions of the adults, about the size of a pinhead. Their eggs, called nits, are tiny, oval-shaped, yellow to white specks. While head lice nits are commonly found on hair, body lice nits are predominantly attached firmly to the seams and fibers of clothing, especially in areas like the waistline and armpits. Occasionally, they may also be seen on body hairs.
Skin Reactions to Infestation
Body lice bites cause specific skin reactions. Small, red bumps or lesions often appear in lines or clusters. These bites cause intense itching, an allergic reaction to the louse’s saliva. Persistent scratching can lead to a red, irritated rash, sometimes developing into scabs or crusts.
Prolonged infestation can lead to more noticeable skin changes. Affected areas may become thickened and discolored, appearing darkened or rust-colored. This is sometimes called “vagabond’s disease”. Constant scratching can also break the skin barrier, creating open sores that are vulnerable to bacterial infections, which may manifest as pus-filled lesions or impetigo.
Where to Inspect for Body Lice
Body lice primarily reside in clothing seams and folds that contact the skin. Bites and skin reactions are most commonly observed in these areas. Specific body regions to inspect include the trunk, such as the torso, back, and abdomen. Other frequent sites for bites and irritation are the shoulders, armpits, groin, and neck, especially where clothing fits snugly or gathers.
Lice move onto the skin only to feed, then retreat to clothing afterward. A thorough examination of clothing seams, particularly around the waist and under the arms, is important for identifying an infestation. While less common, body lice might be seen crawling on the skin when they are actively feeding.