Head Lice: What They Are and How to Get Rid of Them
Published: 03 March 2020
Published: 03 March 2020
If you’ve ever had head lice, you’ll know that they aren’t easy to get rid of. So much so, in fact, they’ve managed to exist for thousands of years - head lice were even around long before human evolution (Better Health Channel 2018).
Head lice are small wingless biting insects. They live and breed in human hair and feed on blood from the scalp.
An adult louse can range from a whitish-brown to reddish-brown colour and is about two to four millimetres in length. Lice eggs, called ‘nits’, are oblong-shaped, white or brown in colour and attached to hair shafts (SA Health, 2019). The warmth from the human head acts as an incubator, causing the nits to hatch (Better Health Channel 2018).
Once a female louse has laid her first eggs on a new host, they will hatch after seven to ten days. From here, the nits will progress through their short life cycle consisting of three stages: egg, nymph and adult. The total lifespan of a louse is only 32-35 days, but after mating, each female can lay three to ten eggs per day. These eggs will then hatch and continue the cycle (Health VIC n.d.).
As long as there are living eggs or lice on a person’s head, that individual is infectious to others (SA Health 2019).
Lice are transferred between people through direct head-to-head contact. They can not fly or jump but will crawl from one person to another (Health VIC n.d.).
Lice spread through being in close proximity to others in times such as playing and cuddling, so children and families are most commonly affected (Better Health Channel 2018).
Without a human host, lice can not survive for more than two days (SA Health 2019).
There are different species of lice that live on animals such as dogs and cats, but they can not be spread to people, and vice-versa (SA Health 2019).
Head lice can sometimes be transferred by using or sharing items that someone with lice has recently used. These items may include:
(SA Health 2019, Mayo Clinic 2018)
Head lice are commonly associated with itching on the scalp, neck and ears, which is caused by an allergic reaction to louse saliva. However, many people will not experience any itching, and it is possible to have a lice infestation without knowing (Mayo Clinic 2018).
The best way to detect lice is to use the ‘conditioner and combing’ or ‘mechanical’ method (Health VIC n.d.).
These are the steps:
(Better Health Channel 2018; Health NSW 2014)
This process should be repeated every second to third day until no more lice or nits can be found (Health NSW 2014).
(Health NSW 2014; Health VIC n.d; Better Health Channel 2018.)
There is no product that can prevent head lice. However, there are some strategies that may help stop lice from spreading. These include:
(SA Health 2019; CDC 2019)
Once someone has successfully treated head lice, the following strategies may stop them from coming back:
(KidsHealth 2019; SA Health 2019)
Although head lice can be tricky to deal with, they are not dangerous and do not spread disease (Healthdirect 2018).
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