An ectoparasitic infection occurs when an ectoparasite uses a human as its host. Ectoparasites infect only the upper layers of the skin, and while their relationship with their human host is beneficial to them, it is harmful to the human. The two ectoparasitic infections that are sexually transmitted include scabies and pubic lice, also known as crabs or pediculosis. Pubic lice live in the pubic hair of a person. They are tiny insects that survive by feeding on human blood.
Pubic lice are not found on the head or skin, but they can be found in other places with similar hair, like the armpits, chest, facial hair, and even the eyebrows. While pubic lice are very common, they don’t actually spread infection. They’re just itchy and annoying. Scabies occurs when tiny mites enter the top layers of the skin, where they live and reproduce. Scabies spreads due to continued close contact with infected persons, making sexual intercourse one of the most common ways scabies spreads.
The symptoms of scabies and pubic lice share some similarities, but because they are caused by two different organisms in different parts of the body, they also have some differences.
Symptoms of pubic lice include:
Symptoms of scabies include:
Both of these ectoparasitic infections mainly spread through sexual intercourse and are classified as sexually transmitted diseases (STD). However, it can happen from sharing linens with an infected person. Scabies can also be spread from person to person among those who live in crowded quarters, in the elderly, and in healthcare settings.
Risk factors for pubic lice include already having a STD. Risk factors for scabies include working in healthcare and age, as the elderly may be more likely to spread it from person to person when it’s spread in a non-sexual manner, as many elderly people live in close quarters.
A healthcare provider can definitively diagnose pubic lice using a microscope or doing an exam of the affected area. They can diagnose scabies either by looking at the skin or getting a swab of skin cells to examine under a microscope for the mite that causes scabies.
Complications of pubic lice include:
Complications of scabies include:
Treatment for pubic lice involves using special creams and shampoos to kill the lice. These are usually sold over the counter, without the need for a prescription, although it’s always a good idea to see a doctor.
In addition to applying these treatments, check in other areas of the body for lice to ensure you’re getting all of them, clean clothes, towels, and linens using hot water and hot air in the dryer, seal items that cannot be washed for 2 weeks from the start of treatment, do not use insect killer, put your sex life on hold for 2 weeks, and repeat treatment if the lice remain in 10 days.
Treatment for scabies involves use of a medicinal cream that needs to be ordered by a doctor. You can also take anti-allergy medication to help with the itching.