Itchy Skin Infestation

STDs scabies images

scabies on the wrist
Scabies on a patient's wrist



What Is Scabies?
How Do You Catch Scabies?
What Are The Symptoms?
How Is It Diagnosed?
What Is The Treatment For Scabies?
Can Scabies Be Prevented?
What Is Norwegian Crusted Scabies?

Return To Main Article

Sexually Transmitted Diseases


Crusted Scabies

What Is Scabies?

Scabies is a highly contagious parasite infection of the skin. It occurs when mites called Sarcoptes scabiei burrow under the skin and deposit their eggs and feces. The result is agonizing itching particularly at night and after exercising. Scratching can lead to broken areas of skin which exposes the person to infestation by other microorganisms. Infestations are particularly common on the wrists, between the fingers, armpits, breasts, soles of the feet, labia (visible part of the vulva) and buttocks. When scabies is transmitted through sexual contact it is considered a sexually transmitted disease (STD). It can be a very annoying condition which, if untreated, can last for years. Scabies should not be confused with pubic lice (crabs), which is another common STD.

Scabies: The Parasite

The mite Sarcoptes scabiei are 8-legged parasites about 1/3 of a millimeter long. They can only be seen with a microscope or magnifying glass. They are unable to fly or jump, they can only crawl. Mites are immobile below 20 C temperatures but can survive and reproduce for prolonged periods at the right temperature. Scabies infestations have been reported by humans for over 2,500 years and 300 million cases still occur worldwide every year.

How Do You Catch Scabies?

Scabies are transferred by skin to skin contact. Sexual contact is one of the most common ways to catch an infection. It is nearly impossible however to get infected by shaking hands, or through bed linen and towels (but cases have been documented). From time to time epidemics are reported in nursing homes and hospitals. You cannot catch scabies from animals. The type of parasite that infects cats and dogs are different - if they land on human skin they can produce a mild itch but die quickly and do not spread.

What Are The Symptoms?

The first time you are infected it may take a month before symptoms appear. Later infestations appear more quickly, sometimes within 24 hours. Signs include:

• Skin rash with small red bumps (called papules) and blisters.
• Rash likely to appear on the elbows, wrists, between the fingers, knees, around the waist, around nipples, on the soles of feet, genital area and buttocks.
• Burrows or tunnels of tiny threadlike projections on the skin (2 to 15 mm long) which appear as thin brown, gray or red lines. Scratching usually destroys burrows.
• Itching is worse at night and progressively becomes worse if untreated.

Tip: Learn to recognize common symptoms of STDs and warning signs.

How Is It Diagnosed?

The symptoms of scabies are similar to many other skin complaints, including hives, eczema, mosquito bites, poison ivy and allergic reactions. Your doctor will be able to differentiate between these conditions by taking a scraping of a burrow or blister and examining it under a microscope. If mites or their eggs are present a diagnosis will be made. If a person shows all the characteristic signs of infection, a scraping may not be necessary before treatment is recommended.

What Is The Treatment For Scabies?

Topical Creams And Lotions
There are no approved over the counter medications for treating scabies, although Nix (for the treatment of crabs) may be effective. Kwell (lindane) is a prescription lotion which is applied from the neck down and washed off after 8 hours. As lindane is a powerful medication that can cause seizures, it should not be used if the rash is extensive with open cuts or after a bath when the skin pores are open. Neither should it be used by pregnant or breastfeeding women, elderly people, those weighing less than 110 pounds and children under the age of 2. Another alternative prescription medication is Elimite (permethrin), a cream which is applied from the head down to the soles of the feet. It is left on overnight and washed off in the morning. It may require a second application. Crotamiton lotions and creams (Crotan, Eurax) are other approved drugs for treating scabies but studies show they are less effective. Sulfur petrolatum (applied as a cream or ointment) is an age old home remedy treatment for the disease. It may be considered if other topical lotions cannot be tolerated - sulfur is safe for example for pregnant women and infants.

Oral Medications
It topical creams and ointments fail to clear the infection; an oral medication called Ivermectin will be prescribed. Although not specifically approved by the FDA for treating scabies, it is taken as a single dose and repeated two weeks later. You may also take antihistamines (Benadryl) to help provide relief from itching while other treatments kick in.

Washing Linen
You should wash and machine dry all bed linen and towels. As mites don't live long outside of the body, there is no need to wash all the clothes in your wardrobe or spray furniture (although you may wish to do so anyway). Sexual partners should also be treated, regardless if they show signs of infection or not.

Prognosis - Outcome

It can take a few days after treatment for itching to subside; it is not an instant cure. It may take a week or two before all itching disappears.

Can Scabies Be Prevented?

Following STD prevention advice can help prevent the spread of scabies. In addition, as scabies can occasionally spread through objects, where possible avoid sharing towels with other people and cover public toilet seats with tissue paper. If you have been infected with scabies, you should contact your doctor or STD clinic for STD testing - you have exposed to other nasty conditions without realizing it.

What Is Norwegian Crusted Scabies?

It is a severe form of scabies first described by Norwegian doctors. It nearly always affects elderly people whose immune system is compromised as well as those who are physically disabled or in patients with AIDS/HIV or lymphoma. Due to the body's poor response to fighting infection, the person becomes infected with thousands of mites. Lesions spread all over the body and the scaly areas eventually take on a crusted, wart-like appearance. Interestingly, the person is likely to have little or no itching.

  Related Articles on STDs

For more advice on sexual health, see the following:

Gonorrhea and trichomoniasis: Common STDs, know the signs.
Genital warts: What they look like and what it means.
Bones and joint problems: Symptom-checker.

Back to Homepage: Womens Health Advice

original content

Please Note: Information provided on this site is no substitute for professional medical help. See Disclaimer.
Copyright. All rights reserved.