Head Lice Facts

Head lice (scientific name Pediculus humanus capitis) have been bothering humans for thousands of years. Archaeologists have discovered lice combs made of materials like bone and ivory, and even preserved nits in the hair of mummified human remains, dating back over 10,000 years. The relationship between humans and head lice is indeed an ancient one!

Head lice are found globally, regardless of climate, cleanliness, or socioeconomic status. This widespread presence indicates that virtually anyone can become infested.

Head lice are ectoparasites that feed on human blood several times a day. Their bites may lead to an allergic reaction, causing red, irritated bumps on the scalp, often accompanied by intense itching. The warmth and moisture of the human scalp provide the perfect environment for them to thrive, and they are entirely dependent on human hosts to survive.

Without a human host, head lice can only survive 1 to 2 days. Their dependence on human blood limits their ability to infest environments away from human contact.

Adult head lice are quite small, about 2-3 millimetres long and are tan or greyish-white which helps them blend into various hair shades. Their tiny size allows them to navigate and hide within the human hair, making detection without careful examination challenging.

Check out our head lice pictures to see for yourself just how small these pests can be!

Head lice have six legs, each equipped with claws that allow them to tightly grasp human hair, making them resistant normal washing or brushing. However, despite common myths, head lice cannot jump! While their movement might seem "quick" in the context of crawling through hair, particularly when they are trying to evade detection or removal, they are not known for their raw speed and cannot jump between hair strands.

Female lice can lay several eggs (nits) per day, attaching them securely to hair shafts near the scalp. Head lice typically live about 30 days on a human scalp. The rapid reproduction rate can quickly lead to a full-blown infestation if left unchecked: a single adult female lice can lay over a hundred eggs in her lifetime! Learn more about the life cycle of head lice.

Head lice can close their spiracles (the equivalent of nostrils) to protect themselves from water and some chemical treatments, allowing them to survive underwater for several hours.

Head lice cannot survive extreme temperatures, such as very hot water or freezing cold. This sensitivity is often utilized in treatment strategies like washing infested clothing in hot water or freezing personal items.

Children between ages 3 and 11 are the most commonly affected group. Their close physical interactions make them more susceptible to infestations, leading to frequent outbreaks in schools and childcare settings. According to NSW Health, studies suggest that approximately 1 in 4 primary school children in Australia have head lice!

Here’s a head-scratcher for you: a study found that as little as 35% of children with a head lice infestation actually had itchy scalps. This is why regular checks are so important! Be sure to also check the entire family for head lice to prevent re-infestations.

Head lice primarily spread through direct head-to-head contact. School-aged children are especially susceptible due to their close interactions during play. Indirect transmission via personal items, such as hats or headphones, is less common but possible.

Many people wrongfully associate head lice with being dirty; however, head lice infestations have nothing to do with cleanliness! Your chances of getting head lice remain the same no matter your personal hygiene.

Head lice are not vectors for any known diseases, making them less of a medical concern. The primary issues associated with infestations are discomfort, irritation, and social stigma.

While head lice themselves don’t carry any diseases, bites from head lice often (but not always) lead to itching and scratching, which may result in secondary skin infections in severe cases if not treated properly. The itching sensation might not develop immediately after infestation, if at all, complicating early detection.

While head lice don’t discriminate, some people may - head lice infestations are all too often stigmatized which may lead to embarrassment or reluctance to seek treatment. It’s important to remember that head lice can happen to anyone and prompt treatment is advised.

Effective treatment often involves a combination of specialized products, thorough combing with a fine-toothed comb and active prevention techniques to prevent reinfestation.