As some parents will already know, head lice infestations can be very difficult to treat. Typically a toxic shampoo or lotion has to first be applied to the sufferer's scalp, after which the lice are removed by pulling a specialized comb through their hair. Louse eggs aren't harmed by such shampoos, however, so the treatment needs to be repeated once they've hatched. This means more nasty chemicals, and more discomfort for the child (or adult). That's why researchers at Germany's Fraunhofer Institute for Surface Engineering and Thin Films have developed an alternative, in the form of a comb that zaps the pests with cold plasma.
Already in use in some German pediatric clinics, the comb has conductive teeth that serve as electrodes. When electrical pulses are sent to those teeth, the air space between them is ionized, generating plasma. Exposure to that plasma kills both adult lice and their eggs, which are known as nits.
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Because the pulses are very short, however, the plasma is no warmer than room temperature. Therefore, there's no danger of burns or singeing to the patient.
Just one treatment reportedly kills half of the lice and nits immediately, with the other half dying within a day. No chemicals or second treatments are required. Additionally, by altering the spacing between the teeth, the comb could be used on pets.
Plans call for it to be brought to market soon, initially in small production batches.
Scientists at the University of Utah previously had success with another form of chemical-free louse treatment, in which hot air was used to kill them.