Scabies
What is scabies?
Scabies is a skin disease caused by a parasite named Sarcoptes scabei. The female parasite burrows under the skin and begins laying eggs within 2-3 hours of infection and generally lays 2-3 eggs daily. The eggs hatch and become adult mites (a term referring to this parasite) within 10 days.
How do you get scabies?
Sexual transmission: transmission is more likely to occur when partners spend the night together than with a brief sexual encounter.
Nonsexual transmission : possibly from sleeping in infested bedding, wearing infested clothing, even routine contact such as shaking or holding hands. Transmission from a toilet seat may be possible, but is unlikely.
How long does it take before symptoms appear?
The female mite burrows under the skin and begins laying eggs within hours (2-3 eggs daily). The eggs hatch and become adult mites within 10 days. Symptoms, primarily itching, appear approximately4 weeks from the time of contact as a result of sensitization to the presence of immature mites.
How long are you infectious?
A person with scabies is considered infectious as long as they have not been treated. Infested pieces of clothing and bedding are considered infectious until treated. After treatment, a person may unknowingly re-infest themselves by coming into contact with the same person who had scabies to begin with or with someone else who has scabies.
What are the symptoms of scabies?
- Presence of the mite burrow(s), reddish brown nodules or lesions, and persistent itching. Itching is known to worsen at night.
- Common sites are: webs and sides of fingers and toes, pubic and groin area, armpits, bends of elbows and knees, wrists, navel, breasts, lower portion of buttocks, occasionally the penis and scrotum, waist and abdomen; they are rarely found on the palms of the hands and soles of the feet, and rarely from the neck upward.
How is scabies diagnosed?
- Microscopic exams of scrapings from suspicious lesion(s).
- Diagnosis is simple if family members present classic symptoms.
- BIT - Burrow Ink Test may also indicate scabies. (The suspicious area is rubbed with ink from a fountain pen. The surface is then wiped off with an alcohol pad; if the person is infected with scabies, the characteristic zig-zag line of the burrow across the skin will appear.)
- Shave biopsies -- a very fine layer of skin is shaved off and examined under a light microscope.
- Topical tetracycline may be applied to the area and examined under a special light to detect the burrows.
How is scabies treated?
- Recommended treatment is Permethrin (RID; A-200) cream applied to all areas of the body from the neck down.
- Alternative Treatments: Kwell (Lindane) or Sulfur. NOTE: Kwell (Lindane) should not be used after a bath; should not be used by (a) persons with extensive dermatitis; (b) pregnant or lactating women; and, (c) children under 2 years.
- Wear clean clothing and sleep between freshly laundered bed linens after treatment.
- Bedding and clothing should be washed and dried at very hot settings or dry cleaned. Family members and close contacts may be treated simultaneously (depending on doctor's recommendation).
- Fumigation of living areas is not necessary.
- After treatment symptoms may persist, but a person may not be infectious.
What else do I need to do to get rid of scabies through sexual contact?
- Use medication as directed; treat all partners.
- Abstain from intimate or sexual contact until the treatment is complete and successful.
- Retest for cure is advised.
- Wash (using hot cycle) or dry clean clothing or bed linen used by an infected person within the past2 days.
How can I keep from getting scabies?
- Abstinence (not having sex) is the best form of prevention.
- Mutual monogamy (having sex with sex with only 1 uninfected partner who only has sex with you) is effective.
- Limit the number of sexual partners to reduce exposure to all STDs.
- Use latex condoms for all types of sexual penetration (oral, vaginal, anal).Note: Latex condoms, when used consistently and correctly, can reduce the risk of transmission of other STDs, but are not considered effective against scabies.
- Know your partner(s). Careful consideration and open communication between partners may protect all partners involved from infection.
- Have regular check-ups if you are sexually active.
- If you have an STD, don't have sex (oral, vaginal, or anal) until all partners have been treated.
- Prompt, qualified, and appropriate medical intervention and treatment and follow-up are important steps in breaking the disease cycle.
What about complications from scabies?
- Kwell may be harmful to the fetus of pregnant women and may damage the nervous systems of newborns and children under the age of two.
- Secondary bacterial infections may be caused by aggressive scratching.
- Scabies is not usually known to cause anything more than discomfort and inconvenience.
Where can I get more information?
Illinois Department of Public Health
HIV/STD Hotline 800-243-2437 (TTY 800-782-0423)
Centers for Disease Control and Prevention (CDC)
CDC-INFO Hotline (24 hours, 7 days a week)
STD information and referrals to STD Clinics
800-CDC-INFO (800-232-4636)
TTY: 888-232-6348
In English, en Español
CDC National Prevention Information Network (NPIN)
P.O. Box 6003
Rockville, MD 20849-6003
800-458-5231
888-282-7681 Fax
800-243-7012 TTY
E-mail:info@cdcnpin.org
American Social Health Association (ASHA)
P. O. Box 13827
Research Triangle Park, NC 27709-3827
800-783-9877
