Head lice live and breed on the scalp. Children with head lice are often isolated and treated with topical applications designed to poison and kill the lice, but these treatments are not always effective. In many cases, they are unnecessary and in some cases they are more dangerous than the lice themselves, which are relatively harmless.
Contamination
One danger of head lice is the possibility of contamination. This can occur in schools, where hundreds of children may be exposed to contaminated students, but is most often attributable to conditions in the home. The danger is lower than assumed, however, as direct head-to-head contract is the usual method of transfer, according to SchoolNurse.com. Lice that fall from a child's head are often injured or dying, and are incapable of establishing a new population.
Scalp Irritation
Feces from lice can cause itching and scalp irritation. Children who scratch their scalp in response to irritation can further irritate the skin. Excessive scratching may also break the skin, exposing the child to possible skin infections.
Dangers of Lice Treatments
Pediculicides are not considered 100 percent effective in treating head lice. They can also be dangerous if used in quantities above the recommended dose or left on too long. Some head lice treatments may contain Lindane, which is a neurotoxin banned in the United Kingdom and is not recommended by consumer reports. Many lice sprays may also be harmful to children and pets, according to HeadLiceInfo.com.
Overreactions to Head Lice
SchoolNurse.com lists overreaction and over-treatment as some of the most common dangers of head lice. Fumigation of schools, buses and other public buildings can be expensive and often unnecessary. Children with lice can often miss out on important time in school because of no-nit policies which require them to stay at home. Lice populations can not sustain themselves due to their small sizes, which eventually lead to destructive inbreeding and the death of the population, so many of the concerns and treatments surrounding them are unnecessary.
