Head lice: Misinformation, resistance in the pediatrician’s office

Summer is nearly upon us, and for many children in the United States, the season is about enjoying sun, sand, summer camp and sleepovers. However, many pediatricians will be spending the summer helping patients and their families deal with an unwanted guest:  Pediculus humanus capitis, or the head louse.

Considered one of the oldest parasites, head lice are known to predate modern Homo sapiens by about 1.18 million years. Unable to fly or jump, head lice are neither ambulant nor particularly hardy parasites, dying within 1 or 2 days once removed from the scalp; they are, however, uniquely adapted to anchor themselves to hair shafts on the human head. Additionally, as a species-specific parasite, head lice cannot be spread through contact with animals, leaving humans as their sole source of food as well as their only means of transportation and dissemination to new hosts.

“Head lice have been with humans for thousands of years,” said Joseph A. Bocchini Jr., MD, FAAP, a professor and chairman of pediatrics at Louisiana State University Health — Shreveport. “They are well adapted to humans and, in fact, their entire life cycle is completed on the scalp. It is a well-developed relationship for the head louse.”

Despite their largely immobile lifestyle, head lice are reported to be responsible for an estimated 6 million to 12 million infestations each year in the U.S. among children aged 3 to 11 years; this age demographic is also most likely to gather in settings where summer activities with the direct head-to-head contact that head lice need to thrive are likely to occur, such as playgrouds, summer camps and slumber parties.

Confronting head lice myths, misconceptions

Although a common issue among children, and not associated with any disease risk, head lice infestations nevertheless Confronting head lice myths, misconceptions. Among the widespread myths about head lice, their association with poor hygiene has been the most difficult to debunk, according to Ashley A. DeHudy, MD, MPH, from the University of Michigan’s Mott Children’s Hospital. “It is important for families to know that this is a very common diagnosis that many people deal with. Anyone is at risk for lice infestation, since according to the CDC, personal hygiene and environmental cleanliness do not play a role in lice.”

In a study published in the International Journal of Dermatology, Parison and colleagues determined that the societal impact of head lice countermeasures, including quarantine and overtreatment, may have a more damaging effect on parents and children than the actual head lice infestation itself. Compared with perceptions of head lice in traditional societies, researchers found that parent populations in the U.S., Canada and Australia exhibited overwhelmingly negative emotions regarding head lice, further contributing to persistent head lice stigma.

While affirming that head lice infestation is common, regardless of socioeconomic status or living conditions, pediatricians are often forced to confront the misconception that head lice spread diseases. Unlike their larger cousins — the body louse, known to carry diseases such as typhus and trench fever — head lice are not a disease vector, although excessive scratching can occasionally increase the risk of a secondary skin infections.

“Head lice do not carry disease, as [they are] different than the body louse,” Bocchini said. “Head lice do not transmit any known infection.”

Additionally, pediatricians are encouraged to spend time educating parents about lice transmission, namely that people become infested with head lice, but inanimate objects or homes do not. Sleeping in a bed formerly used by a person with head lice, for example, is unlikely to spread head lice; however, sharing a bed or spending extended periods of time with heads close together – such as at a sleepover – represents significant risk factors for transmission, providing lice with sufficient time to crawl from one head to the other.

“Head lice often become a problem when people are concentrated together in one place, so naturally we think about children in the classroom, yet even more so during activities like summer camps; whenever people are head-to-head, that is when there is the greatest risk of exposure,” DeHudy told Infectious Diseases in Children.