Humid conditions have helped lice to thrive and a number of schools are said to be desperate for term to end to put a stop to their spread.
However there are fears that as millions descend on Britain for the Olympics the crowds could fuel the problem, particularly in London.
With June’s weather the wettest on record and no let up in the soggy conditions expected until at least next month, climactic conditions are aiding the spread of the nits – while the bugs are also building up resistance to conventional treatments.
Ian Burgess, director of insect research and development at the Medical Entomology Centre, told the Evening Standard: “We have had lots of damp weather and our studies suggest this has caused a higher level of lice than normal.
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“The weather has also meant more children indoors and in close contact which has increased the speed at which the infestation has spread.
“Currently our research suggests about 10 per cent of pupils in a school have nits, which in an average primary school is about 40 at any one time.
“Chances are this is also being passed on from these children to their siblings and even their parents, who in turn can pass it on to their colleagues at work and fellow commuters.
“Lice have also built up some resistance to treatments such as pesticides, so the incidence of lice has risen dramatically over the past few generations.”
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Dee Wright, who runs a north London company called Hairforce which specialises in lice-busting treatments, said there had been a noticeable increase in the problem inn recent months.
She said the ordeal of having nits could be “traumatic” for those who were “constantly re-infected”.
There had been a “real pick-up” among adults, who currently represented a quarter of clients, she added.
“In this weather, there is a big pick-up, there is a lot around. We have heard from our clients, talking about schools where their children are, that there are real problems, and everybody is desperate for term to end so they don’t have to deal with them.”
Recent figures showed there had been a 15% rise in lice so far this year, with those living or working in large cities and using public transport regularly worst affected.
Head lice spread mainly through direct physical contact with a carrier but can also be caught from objects they have crawled onto from a carrier.
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Over half of Britain's four to 11 years olds catch lice every year and £33 million is spent on products annually showing head lice is already at epidemic levels among children and those close to them.
Parents take 2.78 million days off work each year and children miss 2.73 million days of school because they are infested with the itchy insects.
Helping the bugs to flourish is the fact that 53% of people who catch lice are asymptomatic, which means they will not even realise they have nits until it reaches full infestation and their hair is crawling with thousands of lice.
Although there are many products available over the counter, lice are immune to them 80 per cent of the time - leading to a costly and uncomfortable process of trying to tackle the problem head on.
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