What is scabies?
Scabies is an itchy skin infestation caused by a small mite called Sarcoptes scabiei. Intense itching occurs as the mites burrow and lay eggs inside the skin.
Scabies is an infectious disease that can spread rapidly through close physical contact between family members, childcare group, school class, or nursing home. Since scabies can be transmitted to others easily, doctors often recommend treatment for families or entire contact groups.
Scabies can be easily treated. Medicines are applied to the skin to kill the mites and their eggs that cause scabies. However, you may experience some itching for several weeks after treatment.
What are the symptoms of scabies?
- Severe itching that worsens at night
- Irregular, thin tracks consisting of small blisters or bumps on the skin
The tracks usually appear in the folds of the skin. Although it can affect almost any area of the body, scabies is most often found between the fingers, in the armpits, around the waist, on the inner elbows, on the soles of the feet, around the breasts, around the male genital area, on the buttocks, and the knees.
If you have ever had scabies, signs and symptoms may appear within a few days of exposure. If you have never had scabies, it may take up to six weeks for signs and symptoms to appear. You can still transmit a scabies infection even if you do not have any signs or symptoms yet.
What are the causes of scabies?
The eight-legged mite that causes scabies in humans is microscopic. Only female mites dig burrows under your skin to create a tunnel where they will lay eggs.
Then the eggs hatch and the mite larvae dig their way to the surface of your skin, where they mature and spread to other areas of your skin or other people. The itch from scabies results from your body’s allergic reaction to the mites, their eggs, and wastes.
The mites can spread through direct physical contact, and in a few cases, by sharing clothing and bedding with an infected person.
What are the complications of scabies?
Intense itching causes cracks in the skin and leads to a secondary bacterial infection, such as impetigo. Impetigo is a superficial infection of the skin, often caused by bacteria (streptococcus) or streptococcus bacteria (Streptococcus pyogenes).
There is a more severe form of scabies, and it is called crusted scabies. It may affect certain high-risk groups, including the following:
- People with chronic diseases that weaken the immune system, such as HIV or chronic leukemia.
- People with severe illnesses, such as people in hospitals.
- Older people in nursing homes.
Crusted scabies usually causes the skin to crust over large areas of the body. This condition is very contagious and difficult to treat.
Usually, a person with scabies has about 10 to 15 mites. Conversely, a person with crusty scabies may be infested with millions of mites.
How is scabies diagnosed?
To diagnose scabies, the doctor will examine the skin to look for signs indicating the presence of mites, including the burrows that are specific to scabies. When your doctor determines the location of the scabies burrow, they may take a scab from this area of skin for examination under a microscope. A microscopic examination can determine the presence of the mites or their eggs.
How is scabies treated?
Treatment for scabies involves eliminating the parasitic infestations with medication. The doctor can prescribe several creams and lotions to eliminate the infestation.
Your doctor will likely ask you to apply the medicine all over your body, from the neck to the lower body, and leave it on for at least eight to ten hours. Some treatments require a second use, and if a new scab and a rash appear, the treatments should be repeated.
Medicines commonly prescribed for scabies include:
- Permethrin cream. Permethrin is a topical cream that contains chemicals that kill the scabies mites and their eggs. It is generally safe for adults, pregnant women, and children two months of age and older.
- Lindane. This drug is only recommended for people who cannot tolerate other approved treatments or for whom other treatments have not worked. This medicine is not safe for children under ten years old, pregnant, or breastfeeding women, or anyone weighing less than fifty kilograms.
- Ivermectin. Doctors may prescribe this oral medication for people whose immune systems have changed, people who have had scabies (crusted scabies), or those who do not respond to the types of creams prescribed. Ivermectin is not recommended for pregnant or breastfeeding women or for children who weigh less than fifteen kg.
Although these medications kill the mites immediately, you may find that the itching does not stop until several weeks after the treatment.