Scabies is a common skin infestation caused due to tiny mites called Sarcoptes scabiei. These mites are microscopic in nature and can live on your skin for few months. These mites have the ability to grow and reproduce on your skin surface and burrow into your skin and lay eggs. This can lead to an itchy, pimple-like rash that will develop on the surface of your skin.
Around 300 million scabies cases are reported every year. It is a highly contagious condition that can spread from one person to another through direct skin contact. The infection can also spread when you make use of personal items of an infected individual.
Individuals infected with scabies generally show visible symptoms in six weeks of infection. The symptoms appear more quickly when you have had scabies in the past. The common symptom associate with scabies is intense itching and rash that can get worse overnight.
Continuously itching at the infected are can create sores that may become infected with time. The commonly infected parts in toddlers include:
- Sole of the feet
The site of infection differs with age and the common site of infection in older children and adults include:
- Area between your fingers
The rash that appears during scabies consists of tiny blisters or bumps. In most of the cases the burrow tracks of mites are also seen on the skin surface. The rashes generally appear as tiny raised or discolored lines on your body.
Scabies is generally caused due to a specific mite called Sarcoptes scabiei. These mites are usually small eight-legged parasites and are 1/3 millimeter long. These mites can produce intense itching. The female mites are 0.3mm -0.4mm long whereas, the males are about half the size of female.
These mites can crawl on the surface of your skin, but cannot fly or jump. The mobility is reduced or diminished below the 20C temperature, but they can survive for longer time at these temperatures. Scabies are known to occur in epidemics in nursing homes, long-term care facilities and hospitals.
Scabies transmission is possible through direct contact with the infected individual. These mites can survive only for 24-36 hours away from the host. The common mode of transmission is sexual contact with the infected individual. Thus, it is also considered as a sexually transmitted disease.
Scabies diagnosis is initially done by the presence of typical rash and severe itchy sensation particularly at night time. The exact diagnosis is done by taking the skin samples through scraping it. The A sterilized scalpel blade is used to collect the sample for microscopic observation. With the help of scraping skin sample, it is possible to identify mites, eggs or pellets.
It is difficult to diagnose scabies as taking scraping sample from more than one burrow will reveal only one or two mites. In few rare cases PCR (polymerase chain reaction) testing is done to identify the genetic material associated with scabies.