Head Lice? They Might Be Welcome Guests In The Classroom

In the before times, when the notion of Covid-19 infections keeping kids home from school was not even a glimmer of a thought, the dreaded call or email from a child’s school that there was— gasp!— a case or two of head lice in the classroom would make even the most staid adult scratch one’s head incessantly. This would usually be followed up with a note statinig the obvious fact that said louse-ridden children were promptly removed from the premises, and that your child and all the others would undergo thorough lice checks on arrival to school the next morning. In other words, prepare to make arrangements for your child to be picked up from school at the beginning of the next day, as how could they possibly squeak by without having lice, you wonder, as now your whole body feels itchy.

In this month’s issue of the journal Pediatrics, the American Academy of Pediatrics (AAP) issued a statement and clinical update on evaluation, treatment, and yes, school attendance, when it comes to head lice. This pesky condition, caused by the organism pediculus humanus capitis, has literally been lurking in human scalps for thousands of years. A head louse is a tiny creature, about 3mm long, with six legs. Females lay up to ten eggs per day (often known as “nits”). These nits hang out at the base of the hair shaft, incubating for a week or two. After the egg is hatched (a “nymph” is expelled), it takes another 9 days or so for the louse to reach adulthood. The following day, these new adult lice are ready to mate and repeat the cycle.

The scalp itch comes from the saliva that the louse injects into the scalp, which leads to a tiny local inflammatory (and itchy) reaction. As awful as they can be, lice do not have wings, nor do they jump like crickets from one head to the next. Transmission occurs from direct contact (head to head), or from sharing objects such as hair brushes, combs, hair ties, hats, or helmets. Diagnosing head lice is usually based on symptoms— severe itching, followed by a good look at the scalp. Typically, nits, which can be eggs or egg casings, are easier to see than lice themselves.

Treatment options span the range from manually picking out the lice with specialized combs to shampoos containing the substances permethrin or pyrethrin, which act to kill the lice by paralyzing them. And good old ivermectin, erroneously thought to treat acute Covid-19 infections, does have a role in treating lice outbreaks in adults. Other products such as essential oils placed on the scalp or other household items such as butter, margarine, or mayonnaise washes have been met with inconsistent success.

As itchy as you may feel right now, the new AAP recommendations may either put you at ease or make your skin crawl even more. The first new recommendation states that school screenings for lice are neither effective nor warranted. The American Academy of Pediatrics is actually discouraging this practice. But perhaps the biggest updated guidance is that schools should no longer require children to be nit-free or lice-free to come to school. Education on hygiene, and recognition and treatment of the condition, should be provided by school health offices, but lice and the scalps they are thriving on are no longer required to miss out on school.