WATCH: Mother Combing Millions of Lice out of Her Daughter's Hair

This video shows millions of parasites crawling through a child’s hair in what experts have described as an extreme case of head lice.

The clip, posted on YouTube, shows a mother struggling to run a fine-toothed nit comb through her daughter’s coarse locks, which appear to be filled with white and green creepy crawlies.
As the camera focuses on the comb, countless squirming lice are revealed.

WATCH: Mother Combing Millions of Lice out of Her Daughter's Hair

Dr Alejandra Perotti, a lecturer at the University of Reading’s School of Biological Sciences, identified the infestation as head lice - and said she was shocked at the severity of it.

She told MailOnline: ‘They [infestations] are very common in the UK and in Europe, but not to this level.

‘I work in forensic sciences and these types of cases are found in cases of neglect of children or the elderly.

‘You also see it in cases of homeless people.’

Head lice, also known as pediculosis capitis, are tiny insects that live in human hair, which grow to the size of a sesame seed.

They feed by biting the scalp and feeding on blood.

The females lay eggs close to the root of the hair so they are kept warm by the scalp, and these hatch into more lice which breed and multiply.

Dr Perotti added that in bad cases such as this one, children often develop a condition called ‘plica polonica’ – where all the hairs get glued together and cannot brushed.

She said: ‘This child was almost in that condition.

‘To treat it you have to cut off all the hair. At this moment, they should remove all the hair, to remove the nits - combing and shampoo would not work.'

She added the nits are glued with cement to the hair by the mother louse, very close to the skin.

She continued: ‘So you have to cut the hair very short so the female lice don’t lay eggs.

‘Even if the child gets treatment, they will still get lice for about a year, as the old nits become visible.’

One underused method of treating head lice is to use antibiotics, Dr Perotti said.

She explained: ‘All human lice have a bacterium living inside them.

‘If you treat the person with antibiotics, it's likely the lice will die, because it kills this bacterium inside of them and they can’t survive without it.

‘Any simple, mild antibiotic will kill the lice.’

Dee Wright, founder of the Hairforce salons which offer a specialised ‘Lice Assasins’ service in various parts of the UK, agreed this case is on par with some of the more extreme cases she has faced in her salons.

She told MailOnline: ‘That looks very heavy. We see infestations of that nature.

‘We’ve even seen people with nests. That’s where you’ve got so many lice they’re clumping together.

‘They’re a big ball of lice fighting each other for survival.’

Ms Wright said given the lifespan and breeding capability of the female louse, it’s not hard to see how such extreme infestations occur.

She said: ‘The female only needs to lay once. She lives for 30 days lays up to 10 eggs a day.

‘So you can see how if you have 200 eggs hatching at one time, they grow up and mate, and you’re off. Things move quite quickly and you can be overrun.’

Often this happens because parents don’t check their children’s hair regularly, she added.

Ian Burgess, Director of the Medical Entomology Centre, in Cambridge, told MailOnline it was likely the child had been suffering with the lice for several months.

He said: 'There must be 200-300 adults there, however the combing technique is odd, without any break or cleaning of the comb.

'Strangely, the lice all seem to be stuck to the middle of the comb but I cannot work out why or how.

'This kid would have caught lice in the normal way and then the numbers just grew unchecked because nobody did anything.

'It would take a few months to get to this level.