Scabies: Symptoms, Causes & Treatment

Scabies is a common contagious skin infection caused by a type of very tiny microscopic mite, whose female burrows fine tunnels in the surface layer of the skin and lays its eggs there. The presence of the mite and its waste leads to an allergic reaction in the skin producing scabies' most prominent symptom, intense itching. Scabies is not evidence of poor hygiene, as it spreads easily among people regardless of their level of cleanliness.

The most prominent symptoms of scabies are very intense itching that worsens at night and after a warm bath, and a skin rash in the form of small red bumps or thin lines (the tunnels the mite digs). These signs appear in characteristic places: between the fingers, on the wrists and elbows, around the waist and armpits, and in warm covered body areas. In infants they may appear on the palms, feet, and face. Often more than one family member complains of itching at the same time, which is an important indicator of scabies.

Scabies spreads mainly through prolonged direct skin contact (as among members of one family), and sometimes through sharing bedding and clothes. The doctor often diagnoses it clinically from the rash's appearance and locations and the presence of family itching. Treatment is effective and relies on a medication that kills the mite, either a cream or lotion applied to the whole body from the neck down and left for the prescribed time, or an oral medication in some cases. Two principles are fundamental for successful treatment: treating all close contacts and household members at the same time, even those without symptoms (because symptoms are delayed), and washing clothes, bedding, and towels with hot water and drying them well or isolating them in a bag for several days. It is normal for itching to continue several weeks after successful treatment (as a residual allergic reaction), and this does not necessarily mean treatment failure.

• Very intense itching that worsens at night and after a warm bath.
• A rash with small bumps or thin lines (the tunnels).
• Appears between the fingers, on the wrists, armpits, and around the waist.
• Itching in more than one family member at the same time.

• A microscopic mite that burrows tunnels in the skin and lays its eggs.
• An allergic reaction to the mite and its waste causing itching.
• Spread by prolonged direct skin contact, and sometimes sharing bedding and clothes.

• Clinical diagnosis from the rash's appearance and locations and night itching.
• Simultaneous family itching (an important indicator).
• Sometimes scraping a skin sample to see the mite under the microscope.

The mite-killing medication

• A cream or lotion applied to the whole body from the neck down and left for the prescribed time, or an oral medication in some cases.

Principles essential for success

• Treating all close contacts and household members at the same time (even without symptoms).
• Washing clothes, bedding, and towels with hot water or isolating them in a bag for several days.

Itching may continue for weeks after successful treatment as a residual reaction. This content is educational and does not replace consulting a dermatologist.

• A secondary bacterial infection from intense scratching.
• Spread of infection to the family when not everyone is treated together.
• Reinfection when clothes and bedding are not washed.

• Treating all close contacts at the same time to prevent reinfection.
• Washing clothes and bedding with hot water and isolating what cannot be washed for several days.
• Avoiding prolonged skin contact and sharing clothes with an untreated patient.