How can I prevent the transfer of pediculosis (lice)?

How to Prevent Lice Transfer

The most effective way to prevent lice transmission is to avoid direct head-to-head contact, as this is how lice spread in the vast majority of cases—not through shared objects or environmental surfaces. 1

Primary Prevention Strategy: Avoid Head-to-Head Contact

• Direct scalp-to-scalp contact is the primary transmission route for head lice, as lice cannot hop or fly—they only crawl. 1
• Discourage children from engaging in activities that bring heads together during play, sports, sleepovers, and group activities. 1
• Remind children not to huddle together when using electronic devices, reading, or doing group work. 1

Why Environmental Measures Are Overemphasized

• Fomite transmission (through objects) is much less common than direct contact, despite widespread belief otherwise. 1
• Studies demonstrate that lice found on combs are typically injured or dead, and healthy lice rarely leave a healthy head unless there is heavy infestation. 1
• Examination of 118 classroom floors found zero lice on carpets despite over 14,000 live lice on the heads of 466 children using those classrooms. 1
• Only 4% of pillowcases used by infested individuals had live lice transferred to them overnight. 1

Reasonable Environmental Precautions (Secondary Measures)

While less critical than avoiding head contact, these measures are still prudent:

• Change and wash pillowcases in hot water, as this addresses the small (4%) risk of overnight transfer. 1
• Clean hair care items (combs, brushes, hair accessories) used by someone with active infestation. 1
• Wash recently worn clothing and bedding in hot water. 2
• Do not waste time or money on extensive environmental decontamination—spraying homes with insecticides or pediculicides is not recommended. 3

Household Screening and Management

• Check all household members systematically by parting hair in sections and examining the scalp with good lighting, particularly behind the ears and at the nape of the neck. 4, 2
• Treat only those with confirmed live lice or nits within 1 cm of the scalp—do not treat based on nits alone, as empty egg casings can remain for months after successful treatment. 1, 2
• Treat family members who share a bed with the infested person even if no live lice are found, as this is a prudent precaution. 1

School and Childcare Settings

• Children with head lice should remain in class and not be excluded from school, as head lice have low contagion in classrooms. 1
• Discourage close direct head contact with others once diagnosed, but allow the child to continue normal activities. 1
• "No-nit" policies should be abandoned—they are based on misinformation rather than science and result in unnecessary school exclusion. 1
• Mass screening programs have not been proven effective in reducing head lice incidence over time and are not cost-effective. 1

Special Considerations for High-Risk Situations

• Before and after sleepovers or camps where children share sleeping quarters, carefully check your child's head, as these settings allow easier spread. 1
• Child care centers with close contact among young children may facilitate transmission more readily than school classrooms. 1

Common Pitfalls to Avoid

• Do not panic about shared hats, coats, or classroom materials—these pose minimal risk compared to head-to-head contact. 1
• Do not use preventive pediculicide treatments on children without confirmed infestation, as this contributes to resistance and unnecessary chemical exposure. 1
• Do not keep children home from school once treatment is initiated—this causes unnecessary educational disruption without public health benefit. 1, 2