What is so bad about head lice?

Head liceWe may feel disgusted by the thought of microscopic insects crawling around on our heads, laying their eggs, sucking our blood, and generally making our skin crawl – but head lice aren’t dangerous. In fact, they’re more of a general nuisance than something that can actually harm us.

Head lice are tiny white or grey-brown insects that can live in human hair. When newly hatched they can be smaller than the size of a pinhead and can grow to the size of a sesame seed when fully mature. They’re not great travellers and can’t jump, fly or swim and are only spread between people by direct head-to-head contact when they can climb from the hair of an infected person to the hair of somebody else. Head lice are more commonly found in children between the ages of 4 and 11, although anyone can get them. It’s important to remember that catching head lice isn’t a sign of dirty hair or poor personal hygiene; all types of hair can be affected, regardless of its length and condition.

Some people experience the uncomfortable symptoms of head lice before actually noticing the critters are there whereas others feel no symptoms whatsoever. Head lice bite your skin in order to feed off your blood, the parasites saliva is generally irritating to some people causing the scalp to itch like crazy! People may also develop sores or red raised bumps from scratching their head without realizing why they’re itching so much.

However, these annoying physical symptoms aside, head lice are not considered a medical or public health hazard and are not known to spread any diseases to humans. If you’re interested, you can read about how to spot head lice on the NHS Choices website.

If you’ve just started itching as a result of reading this answer (I’ve been itching the whole time I’ve been writing it!) and think you may have head lice then don’t worry! Similar to yawning, seeing someone itch or even thinking about itching can trick your brain into believing you need to scratch all over. Then again, I think I might just get someone to have a quick look in my hair anyway.

Answer by Nathan Beal

Photo credit : Gilles San Martin, on Flickr


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Article by Nathan Beal

December 11, 2014

Nathan is currently in the throes of a PhD in Computational Chemistry at the University of Manchester. When he’s not behind a computer, he’s outside enjoying the sights of the city. A fan of The Walking Dead, he has a strange apathy to all things football-related.


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