Pronunciation: [hˈɛd lˈa͡ɪsɪz] (IPA) 
The correct spelling of the word is "head lice," not "head lices." The word "lice" is already plural, so there is no need to add an -s to the end of it. The pronunciation of the word "lice" is /laɪs/ in IPA phonetic transcription, with the long "i" sound represented by the /aɪ/ symbol. It is important to use correct spelling and pronunciation when discussing this common problem, which affects many people worldwide.
Head lice, also known as Pediculus humanus capitis, are tiny parasitic insects that infest the human scalp and feed on blood. They are commonly found in children of school-going age, but anyone, regardless of age or personal hygiene, can become infested.
The adult head louse is very small, measuring about 2-3 millimeters in length, and has a tan to grayish-white color. Female head lice lay eggs, known as nits, which stick firmly to the base of hair shafts close to the scalp. Nits are oval-shaped, about the size of a grain of sand, and typically hatch after 7-10 days. Once hatched, the newborn lice grow into adults in about 9-12 days. The entire life cycle lasts approximately 30 days.
Head lice are primarily transmitted through direct head-to-head contact, such as when children share combs, brushes, hats, or pillows. Indirect transmission can occur when personal items such as hats or scarves are shared. Itching is the most common symptom associated with head lice infestation, caused by an allergic reaction to their saliva. Scratching can lead to skin irritation, inflammation, and secondary infections.
Treatment for head lice typically involves the use of over-the-counter or prescription medicated shampoos, lotions, or creams that contain insecticides. Additionally, manual removal of live lice and nits using a fine-toothed comb is necessary to ensure complete eradication. To prevent re-infestation, it is important to thoroughly wash, vacuum, or dry clean personal items, as well as frequently wash bed linens, combs, and brushes. Regular inspection of the scalp can help detect and treat head lice infest
The word "lice" comes from the Old English "lūs", which was derived from the Proto-Germanic root *lūs-. This root has cognates in other Germanic languages such as German "Laus", Dutch "luis", and Old Norse "lús".
The term "head lice" specifically refers to lice that infest the scalp or hair of humans. The word "head" in this context simply denotes the location of the infestation. So, the combination of "head" and "lice" essentially describes lice found on the head.
