Pubic lice spread primarily through sexual contact with an infested person. Often called “crabs” because of their claw-like legs, these tiny parasites crawl from one person’s body hair to another’s during close skin-to-skin contact. While non-sexual transmission is possible, it’s uncommon and requires very specific circumstances.
Sexual Contact Is the Main Route
The overwhelming majority of pubic lice cases result from intimate, skin-to-skin contact with someone who already has them. During sex, the lice crawl directly from one person’s body hair to another’s. Their second and third pairs of legs have large modified claws with thumb-like projections specifically designed for gripping hair shafts, which makes them well-suited for transferring between bodies pressed together.
Condoms do not prevent the spread of pubic lice. Because the lice live in the hair surrounding the genitals rather than on the genitals themselves, a condom covers only a small portion of the area where lice are active. Any form of sexual contact that brings pubic regions close together creates an opportunity for transmission, regardless of barrier protection.
Where They Live on the Body
Pubic lice are most commonly found in the pubic and perianal regions, but they aren’t limited to those areas. They can also infest armpit hair, chest hair, and even mustaches or beards. They need coarse body hair to grip onto, which is why they don’t typically colonize the finer hair on your head (that’s a different species of louse). Any area of coarse body hair that comes into prolonged contact with an infested person’s hair is a potential landing zone.
Spread Through Shared Items
Pubic lice can occasionally spread through shared clothing, bedding, or towels. This happens because a louse that falls off the body can survive for 24 to 48 hours without a blood meal. If you sleep in the same sheets or share a towel with someone who is infested, a stray louse could potentially transfer to you during that short survival window.
That said, this route is genuinely uncommon. Pubic lice are slow-moving parasites that strongly prefer to stay on a warm human host. They don’t jump or fly. Once separated from the body, they’re weakening and dying, not actively seeking a new host. The scenario requires near-immediate reuse of contaminated fabric, which limits how often it actually happens in practice.
Toilet Seats and Other Myths
The CDC describes toilet seat transmission as “very rare.” The logic is simple: a louse would need to have fallen off someone’s body onto the seat and then be picked up by the next person to sit down, all within a window of hours. Because pubic lice grip tightly to hair shafts and don’t survive long away from a host, this chain of events is extremely unlikely. You also cannot get pubic lice from swimming pools, handshakes, hugging, or sitting on furniture in public places.
What You’ll Notice After Exposure
The hallmark symptom is itching in the pubic area, caused by an allergic reaction to louse bites. This itching often takes days to weeks to develop after initial exposure, because your body needs time to become sensitized to the lice saliva. During that delay, you may be unaware you’re infested and could unknowingly pass the lice to a partner.
If you look closely, you may spot tiny tan or grayish-white insects clinging to the base of pubic hairs. Their eggs (called nits) attach firmly to individual hair shafts and look like small oval specks. Some people also notice bluish-gray spots on the skin where lice have been feeding, or small dark specks in their underwear from louse droppings.
The Link to Other STIs
Because pubic lice spread through sexual contact, having them signals potential exposure to other sexually transmitted infections. A large number of people diagnosed with pubic lice also have a concurrent STI. For that reason, a diagnosis of pubic lice typically prompts screening for infections like chlamydia and HIV. The lice themselves don’t transmit these diseases, but the same sexual encounter that passed along the lice may have also exposed you to something else.
Reducing Your Risk
Since condoms don’t help and the lice spread through any close genital contact, your options for prevention are limited. The most effective way to avoid pubic lice is to avoid intimate contact with someone who has them. In practice, that means being aware of symptoms in yourself and your partners: persistent itching in the pubic area, visible lice or nits, or unexplained irritation.
If you know someone in your household is infested, avoid sharing towels, bedding, and clothing until they’ve been treated. Washing potentially contaminated fabrics in hot water and drying them on high heat kills both lice and eggs. Items that can’t be washed can be sealed in a plastic bag for 72 hours, well beyond the 48-hour survival limit for adult lice off the body.
Sexual partners of someone diagnosed with pubic lice should be treated at the same time, even if they don’t yet have symptoms. Reinfestation is common when one partner clears the lice but the other doesn’t, creating a cycle of passing them back and forth.