The symptoms of scabies can resemble many other conditions, all with very different causes and courses of treatment.  Therefore, it is important for patients to correctly identify the condition in order to minimize the discomfort it can cause.  Fortunately, once this first step of recognizing scabies is achieved, the treatment is fairly straightforward and effective.  For the rest of this article, we will explore the key clues central to the presentation of scabies.

Put simply, scabies is an infestation of the skin by a human mite.  This mite burrows into skin, releasing feces and eggs.    The body’s reaction to these products results in the main symptom of scabies: itch.  Before discussing the itch any further, it is helpful to talk about which kind of people get scabies and the circumstances which give rise to the infestation.  Nearly anyone can be affected, regardless of age or socioeconomic status.  Those that tend to get affected more include women, children, and those with crowded living conditions.  The fact that scabies is highly contagious is important as cases tend to occur in clusters or epidemics.  One should determine if family, friends or any other close contact are affected (eg. daycare playmates).  The spread of the mite generally occurs through close physical contact or by sharing items (eg. towels, clothing) with an affected person.  In young adults, spread by sexual contact is common.  Mites are present in the skin for up to a month before symptoms appear, so it may take some reflection to find the triggering event.

As mentioned above, the hallmark symptom of scabies is itch.  The itch is almost always severe and it generally worsens at night.  The itch is especially problematic if it results in interrupted sleep.  Scratching is strongly discouraged as it can lead to breaks in the skin that cause infections.  Although itch is the most common symptom, it isn’t very useful on its own to differentiate from other conditions.

Lesions,  visible on the skin, are another very common symptom of the mite.  The most important thing to look for are burrows, which appear as thread-like lines on the skin, generally a few millimetres in length,  and often having a wavy pattern.  The burrows vary in colour from skin tones to a silvery or white appearance.  They are generally accompanied by raised red bumps on the surrounding skin that can have a rash-like appearance.   Rarely, more serious lesions present due to excessive scratching.    The more serious symptoms may present with a high degree of scaling and pus, or large patches of thickened skin.   This appearance warrants a visit to your doctor to check for weakened immune function or infection.

Common scabies lesions are most commonly found in a few key locations, which include webs of the fingers, sides of the hands and feet, armpits, near the belt line and around the nipples or groin.  The face and scalp may be affected in infants and young children but these areas are usually spared in adults. 

The common symptoms of scabies, itch and lesions, are present in a variety of skin conditions.  Therefore, it is important to look at the specific aspects of these symptoms as mentioned above.  Does the itch worsen at night?  Do the lesions fall in areas that match the distribution mentioned above?  One should also determine if others around them are experiencing similar symptoms, which is likely due to the highly contagious nature of the condition.  One should also consider alternative explanations for these symptoms such as insect bites, atopic dermatitis, psoriasis, impetigo, and lice.

A pharmacist or doctor can help you recognize scabies.  In addition to a detailed history of the symptoms mentioned above, a definitive diagnosis typically involves viewing a scraping of the skin under a microscope for mites, eggs or feces.  It is always recommended that you seek the advice of your caregiver before attempting any kind of self-treatment for scabies.