Head lice infest many fewer people in North America than might be believed by the general public or the medical community. In general, one should expect about one infested child in a school group of 100 children in the kindergarten through 4th grades. Frequently cited references of “6 to 12 million” infestations in the US annually are based upon flawed analyses of marketing statistics. If such statistics were valid, then head louse infestations would truly be rampant. Whereas prevalence is, on average, only about 1% in North America, a greater percentage of children are infested in some other countries. Reasonable explanations for this difference remain elusive.
Reports of ‘epidemics’ of head lice in North America may generally be attributed to frequent incorrect identifications, misdiagnoses and subsequent mass hysteria. Furthermore, the apparent annual and seasonal ‘increases’ in prevalence are most likely attributable to peculiarities in monitoring activities. Indeed, school personnel tend to concentrate their screening efforts at the beginning of each school term. The perception that lice are more prevalent today is probably imaginary, as it may simply reflect a trend toward greater candor in discussing such issues.
As long as there have been - and will be - children with hair, there have been and will likely be kids with head lice. Head louse infestations are not likely any more or less frequent or burdensome then they were in past generations. Somehow, we all survived, and so will our children.