The STI Files: Scabies
Stat: This disease has bothered humans for thousands of years, but it seems to come and go in unexplainable cycles. Scabies used to be very rare in America, but now it is coming back again.
What is it exactly? Scabies ("skay-bees") is a skin disease caused by a mite called Sarcoptes scabiei. The mite can barely be seen by the human eye.
About how many people have it? Unknown, but probably less than 1% of the population has it.
How is it spread? Scabies can be transmitted with non-sexual activities like holding hands or touching infested towels. However, most cases of scabies come from sexual contact because sexual contact gives the mites a lot of time to move from one person to the other. The risk increases if partners spend the night together in the same bed. Even people who share a bed or towel with someone might get infected because mites can live for up to two days on linens.
What are its symptoms? The female mite burrows into skin to lay her eggs which hatch and become adults in 10 days. The first symptom people get is an intense itching from the eggs in the skin. It can take as long as 4 weeks for itching to start, which usually becomes so bad the person cannot sleep. Small red bumps like pimples or lines like small scratches appear where the mite has burrowed into the skin.
Scabies prefer warmer sites on the skin such as skin folds or under tight clothing. Examples include between the fingers, the bend of the elbow, under the arms, the wrists, the buttocks or belt line, around the nipples, and on the penis. Mites also like to be under rings, bracelets, watchbands, and fingernails. They are rarely found above the neck.
If scabies is not treated, the skin may be crusty or scaly. This is more common in older people or people with decreased immunity (like those with AIDS).
How is it diagnosed? Self diagnosis is possible, but difficult. May require microscopic examination of a skin scraping or biopsy.
Is it treatable? Yes. You may need to see a special skin doctor (called a dermatologist) to get the best treatment for you. Most treatments involve a skin cream that is put all over the body for 12 hours. During this time, all bedding and dirty clothing should be washed in hot water and put in a hot drier. Everyone who might also be infected should also be treated during those same 12 hours. This includes people who live with you, people you have close physical contact with, and all sexual partners.
After treatment, the mites will be dead but it takes a while for the symptoms to go away, so it is a good idea to be rechecked by your doctor. If the itching is still a problem, you can take an anti-histamine or use a hydrocortisone cream.
Is it curable? Yes, but you can get it again.
Can it affect fertility? No, but it can damage the nerves of fetuses or children younger than two years old.
Can it cause death? Scabies usually doesn't cause anything more than discomfort and inconvenience, though people who scratch the bites may get more bacterial infections.
How can we protect against it? It is very hard to protect against scabies. If you know someone with scabies, it is best to avoid any sort of physical contact with that person because the mites may be anywhere on their body. Do not share any clothes, towels, or bedding with the person, either, until they have been treated and everything has been washed.