What Is Scabies?

Scabies is a skin condition caused by a parasitic infestation in which mites of the species Sarcoptes scabiei work their way into the skin. Here, they lay eggs, causing a rash and intense itching.

How do you get scabies?

Scabies is spread from person to person by skin contact. Burrowing mites dig into the skin, moving up to 5 millimeters per day. They then stay in their burrows over their 4–6-week lifetime, laying eggs that further spread the infestation. The higher the level of infestation in the affected person and the closeness of the contact influence the risk.

The WHO states that contact with infested clothes, bed linens and other personal items is “unlikely” to result in transmission, except in rare cases. Scabies can be passed from an infested person before they start showing symptoms, due to an asymptomatic incubation period.

What does scabies look like?

According to the WHO, symptoms of scabies include itchy lines – called linear burrows – and bumps – called papules – along the arms, wrists, fingers, legs and waist. In women, the breasts and areolae are particularly affected, as are the penis and scrotum of men. Only 10–15 mites are actually present during an infestation. Scabies in children is thought to involve a greater number of mites and is often not treated thoroughly enough. Complications of the disorder include bacterial infection of the picked-at skin area.

In people with compromised immune systems, the number of mites multiplies exponentially, as the body is unable to fight off the spread. This severe variant is called crusted scabies. This produces a thick crust on the skin, called hyperkeratosis, on the hands, feet, head, neck and elbows. The lack of immune response means that people with crusted scabies don’t itch. People with crusted scabies are extremely contagious.

How is scabies treated?

Scabies is treated using drugs that kill either the mites or their eggs. These include topical permethrin, crotamiton, benzyl benzoate and ivermectin.

Are scabies cases on the rise?

Medic testimonies obtained by The Guardian suggest that a surge in scabies cases is happening across the UK. The problem is exacerbated by a shortage of two major treatment options in the country – permethrin, and the insecticide malathion. Dr. Michael Head, a senior research fellow in global health in the Faculty of Medicine at the University of Southampton, told Technology Networks that awareness would be key to fighting the outbreak: “Scabies is a stigmatized disease, so cases often go unreported. It can also be hard to diagnose and distinguish from other skin conditions, so misdiagnosis can be an issue too.”

Head stated that other treatment options should be considered in response to rising cases: “In the UK, we use permethrin as a first line of treatment. This is a skin lotion that is effective. However, given the shortages, we really should be considering greater use of ivermectin. Ivermectin gained a high profile during the pandemic when it was incorrectly associated with being a useful treatment for COVID-19. However, it is very effective against scabies, and is sometimes used off-license in the UK. We could make more and better use of ivermectin, alongside treatments such as permethrin.”

Head concluded that if treatment shortages continue, the outbreak could be sustained. “Ultimately, if cases are untreated, then the mites often continue to reproduce and the infection and potential for transmission continues,” he said.