super lice

Highly-resistant 'super lice' are taking over Canada and here's what you need to know

Getting hit with a bad case of lice already produces enough stress to make you want to pull your hair out, but being host to a specific strain of the blood-sucking parasites might be even worse, as genetic mutations are helping them become more resistant to conventional treatments. 

While common lice infestations can be treated with insecticide treatments with permethrin and pyrethrin, these historically successful products have proven to be less effective with "super lice." 

These pesky critters look just like any other lice, but their susceptibility in the face of conventional over-the-counter chemicals and medicated shampoos is what makes them so difficult to treat and get rid of. 

Unlike body lice, head lice aren't a primary health hazard or a sign of poor hygiene, but they are relatively expensive to treat, according to the Canadian Paediatric Society.

Head lice are wingless and usually 2 to 4 millimetres long as adults. The six-legged blood-sucking insects live on the human scalp, and infested children usually carry less than 20 mature head lice at a time, which can live three to four weeks without treatment. 

After mating, the troublesome female parasites can produce five or six eggs per day for 30 days, with each one glued to a hair shaft near the scalp. 

Head lice are most commonly spread through direct head-to-head (or hair-to-hair) contact, as they do not hop or fly, but do have the capacity to crawl rapidly. 

Common symptoms of a lice infestation include itching the scalp, and the presence of eggs (nits) in your hair, resulting in itching of the ears and beck, tickling sensation from lice movement, red bumps on the scalp, neck, or shoulders, as well as irritability. 

In recent years, the common nuisance has become more and more difficult to treat, thanks to cases being misdiagnosed and/or treatments being administered incorrectly. 

Since super lice have become more resistant to conventional treatments, doctors are recommending stronger medications, including those containing dimethicone (which suffocates lice), as well as Natroba, Sklice, and Ulesfia

If you're hit with a resistant case of lice, your best course of action is to consult a healthcare professional as soon as possible.

Lead photo by

Protasov AN/Shutterstock


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