A head louse beneath a microscope / Rex

Sure to make anyone itch, thousands of lice crawl around a mans scalp making his hair appear alive

This horrific video shows exactly what can happen if a case of the head lice is left untreated. In the video below you can see the lice crawling onto the mans hairline and across his forehead.

Warning: some viewers may find this disturbing

Head-lice feed from the blood of their human hosts and with an infestation this bad may actually result in the sufferer being incredibly faint and run-down. Information that is sure to have parents of school-aged children itching for the lice-shampoo.

London hair force's Dee Wright told the MailOnline "That's a very extreme case. He will have them in his eyebrows and his eyelashes - they will be falling down." adding  'That person's scalp will be raw in places and infected. That will be running his system down like crazy."

The problem with lice infestations is that its actually incredibly hard to prevent, they are attracted to all types of hair and spread by head to head contact. The best way is to comb hair regularly and check to see if any live louse are on the scalp, using nit shampoo or mouses won't work in prevention and should only be used when lice have been detected in the hair.