What is scabies?
Scabies also known as “craw-craw” is a common skin disease caused by mites. The mites produce rashes (eruptions) in certain parts of the body. These rashes are very itchy; making the infested individuals to scratch all the time. The itching is especially worse at night. Sometimes these rashes can be superinfected with bacterial infections making them to swell, become painful and bring out pus. Children are commonly affected. Scabies can affect adults as well. Males and females are affected equally.
What causes scabies?
The mites that cause scabies are called Sarcoptes scabiei var hominis. The female mites dig (burrow) through the outer layer of the skin and lays 0-4 eggs every day for up to 6 weeks before dying. Primary infestations show an increase in mites’ numbers for up to 4 weeks with a gradual reduction as the infested individuals’ immune system begin to fight back. Animals such as dogs and cats can also have scabies, but are infected by a different type of mite. When humans come in contact with an infested animal, although the animal mites can crawl on to their skin and produce itching, they are unable to multiply and will eventually die within one week. Basically, the human craw-craw is transferred from person to person by prolonged direct skin-to-skin contact as well as through sexual contact with an infested individual. It takes approximately 15-20mins of close contact for direct transmission to be successful.
Factors that encourage the spread of scabies
Overcrowding is one of the important factors that cause the spread of scabies. Individuals in closed-up communities and institutions such as prisons, orphanages, displacement camps (IDPs), barracks are at high risk. Scabies can be localized within a family unit, daycare centers and schools. Sharing blankets and clothing of infected individuals are important factors that also encourage the spread of scabies in our environment since the high environmental temperature and humidity can help the mites to survive outside the skin for at most 3 days. A huge transmission of scabies can occur during war and economic crisis.
Symptoms of scabies infestation usually begin to appear approximately 14 days after the mites have infected the skin of the individual. Itching is noticed in between the fingers, wrists, elbows, shoulders, ankles, under the breasts in women, genital area including the scrotum and penis in males. The infected individual will have scratch marks, small papules/pustules and raised/flattened burrows (home of the mites). Also important is the presence of someone in the same household with similar condition, although may not be as severe. Sometimes, the initial rash may get infected with bacteria or increase in size to form nodules (bumps); as a result of the individual developing allergic reaction to the mites. People that are immunocompromised may develop the crusted form of scabies, also known as Norwegian scabies. This form of scabies is less itchy to the individual and highly contagious (easily spread to other people). The close family members of a patient with Norwegian scabies who gets infested by the mites usually manifest with the normal form of scabies. Scabies infection can sometimes lead to kidney disease known as acute glomerulonephritis especially in those with superimposed bacterial infection by group A streptococci.
Prevention of scabies
People need to know about scabies. Knowledge on the cause, spread and manifestation of scabies will enable early presentation, management and eventual spread of scabies. Patients with rashes resembling scabies need to see the dermatologist for proper diagnosis and treatment.
Infested individuals will be advised to avoid close physical contact until they and their sexual partners have completed treatment. Children must complete treatment before returning to school.
Prompt treatment of those affected and contact tracing is advised. Usually close contact family members are also treated.
Clothing and beddings of infested individuals must be washed in hot water, dried in the sun and ironed properly before being used again. Encourage good and proper general/skin hygiene (bath daily, regular change and wearing of clean clothing, etc). Avoid overcrowding. Maintain sexual discipline.
Different modes of treatment of scabies are available. Please consult a dermatologist near you.