Lice are spread through direct contact as they crawl. Indirect contact (through brushes or hats) is less likely. One study showed that live lice were found in only 4% of infested volunteers pillowcases.
During an initial infestation, lice can reside on the head for up to 4 to 6 weeks before becoming symptomatic. Therefore, when lice are detected at school, there is no need to send the child home (or to the ED). Children also do not need to be kept out of school while receiving treatment.
Bonus: First line treatment is 1% Permethrin applied on day 0 and 9. The patient should wash their hair first with a non conditioned shampoo, apply Permethrin for 10 minutes and then rinse.
References
Devore CD and Schutze G. Head Lice. Pediatrics. 2015; 135 (5) e1355 -e1365.
