One of the worse souvenirs from a vacation is scabies—microscopic mites that can be contracted on planes, trains, ships, in hotel rooms and crowded areas of the world. This is part 3, the last and final stage of our research into this annoying, irritating and sometimes hard to get rid of infestation of the body.
Diagnosing scabies isn’t easy. The parasite mites that cause it may be so few and the burrows they make in the top layers of skin so tiny that they can’t readily be identified. What’s more, the tell-tale pimply, itchy rash of scabies is similar to rashes caused by numerous other conditions, including eczema, drug eruption, heat rash, insect bites, contact dermatitis, a disease called Grover’s and even cancer.
Since dealing with scabies is so difficult (more on this below), it is important to get a diagnosis from a dermatologist asap, especially if you’ve been traveling. The only certain way to identify scabies is to get positive evidence of presence of the mite or its eggs through a skin scraping examined under a microscope. Very few medical generalists will do this, and a scabies diagnosis without a skin scraping will lead to onerous and time-consuming treatment s and protocols that may end up useless.
An experienced dermatologist will examine the skin with a hand-held microscope in order to find likely mites and then use a scalpel to excise samples. Unfortunately, however, mites may be so few that a skin scraping may turn out negative when mites are present—another diagnostic problem.
Difficult diagnosis is only one way dealing with scabies is no walk in the park. After a positive diagnosis, the gold-standard of treatment is the head-to-toe application of 5% permethrin cream that must remain for a minimum of eight hours. The insecticide, a synthetic pyrethroid similar to the natural insecticide in chrysanthemum flowers (but preserved with formaldehyde, a known carcinogen), is massaged into every inch of skin, including between toes and fingers.
However, scabies mites have developed some resistance to permethrin, so it may not work. If a second application a week later appears to fail, oral Stromectol (ivermectin) is usually prescribed. The proprietary Merck drug is FDA-approved to treat parasitic worms, but it is commonly prescribed “off-label” to treat scabies. Two doses 14 days apart are based on the patient’s weight.
While Stromectol has a good track record in treating scabies, a positive cure is difficult to proclaim. The only way to know if a victim is rid of the mites is if no new bumps appear or the old ones don’t gradually fade. At the same time, a maddening itch can last for weeks after the mites are long gone, an allergic reaction to the dead mites.
Meanwhile, the threat of spreading the mites to others and re-infestation of the original victim means an exhausting anti-scabies protocol. Since shed mites can live for three days without a human host, the parasites can lurk on clothing, bedding, towels, furniture, carpet and everything else in the home environment. All of it must be washed or cleaned daily.
And because an infested person can easily spread the mites to anyone they are in close constant contact with, avoiding touch and sleeping alone is important. It is also the reason that all people in a household should get scabies treatment at the same time that the original victim does.
Until a month or so without new symptoms, a scabies sufferer can only hope he or she is cured.