Lice are parasites, living externally on warm-blooded hosts from birds to mammals, including humans. Chewing lice live among the hairs or feathers of their host and feed on skin and debris, while sucking lice pierce the host’s skin and feed on blood and other secretions. Lice need warmth and blood to thrive and once they have found a host, they will settle there and start laying eggs. They usually spend their whole life on a single host, cementing their eggs, which are known as nits, to hairs or feathers. The eggs hatch into nymphs, which moult three times before becoming fully grown, a process that takes about four weeks.
Humans host three species of louse, the head louse, the body louse and the pubic louse. The body louse has the smallest genome of any known insect; it has been used as a model organism and has been the subject of much research.
Lice have no wings or powerful legs for jumping, so they move by using their claw-like legs to transfer from hair to hair. Normally head lice infest a new host only by close contact between individuals, making social contacts among children and parent-child interactions more likely routes of infestation than shared combs, hats, brushes, towels, clothing, beds or closets. Head-to-head contact is by far the most common route of lice transmission. About 6–12 million people, mainly children, are treated annually for head lice in the United States alone. High levels of louse infestations have also been reported from all over the world, including Australia, Denmark, France, Ireland, Israel and Sweden. Keep in mind that head lice can live off the head, for example on soft furnishings such as pillow cases, on hairbrushes, or on coat hoods for up to 48 hours, so it is important to take those into consideration when preparing your prevention measures.
Sometimes it can take up to six weeks for those with lice to experience symptoms such as itching, and other times they lice can be easily noticed before it’s an epidemic. No matter the case, the best way to fight lice is to prevent them from making way into your life.
Advice and solutions for keeping your household lice free
To reduce the risk of you or any member of your family catching a case of head lice, start by not sharing items that touch the head. Avoid sharing thing such as combs and brushes, hair clips and accessories, hats and bike helmets, scarves and coats, towels, headsets or earbuds. Also avoid using the same pillow or any other objects that promote direct head-to-head contact between a carrier and potential carrier. Lice don’t fly, but they crawl, so make it difficult for the little guys to crawl onto your family’s heads. Tie long hair up as often as possible in buns which are a great prevention hairdo, but even braids and ponytails will help minimize the surface area.
Keep in mind that shared spaces and belongings can be breeding places for lice. Places such as closets, lockers, drawers can easily create the opportunity for lice to pass from one person to another.
It is important to know the symptoms of lice and where to find them. The most common symptom of head lice is itchiness in and around the back of the neck. They’re most common around the ears and the back of the neck, and feed off of human blood. They are much more noticeable on darker-colored hair. Because in many children they do not produce symptoms until weeks after they have moved in, regular checks are recommended. The best time is after the child has taken a bath, while the hair is still wet. Especially during winter months, the scalp tends to be dryer and may cause flakes. Make sure those flakes are really the result of dry scalp by pulling them down the shaft of the hair strand. If it’s a flake, it will come off, but if it is a nit (cemented lice egg), it won’t budge.
As head lice mostly affect children, teach them not to share certain objects and not to make contact with lice carriers. Even if the person has had treatment, but two weeks have not passed, it is advised to try and avoid contact with any of their fabrics.
Make sure to regularly wash worn or slept-in items if you suspect anyone in your family has been exposed to a lice infestation. When possible, also do this with the toys your children sleep with. Machine wash and dry clothing, bed linens, and other items that an infested person wore or used during the 2 days before treatment using the hot water (130°F) laundry cycle and the high heat drying cycle. Clothing and items that are not washable can be dry-cleaned or sealed in a plastic bag and store them for 2 weeks. This should allow for enough time to pass and any remaining lice to die, as they usually only hold up for 2 days without food.
You can also soak hair care products in water, isopropyl alcohol or medicated shampoo solution. Items such as brushes, combs, hair ties, headbands, barrettes should be soaked periodically to kill any lice attached to them. There are also several hair products that you can use, which are meant to repel lice, whether they are based on smell or chemical reactions. Such products are usually shampoos or conditioners which contain tea tree oil, or you can also directly use coconut oil, menthol, eucalyptus oil, lavender oil, and rosemary oil, as lice dislike the smell of these strong oils.
As a preventive measure around the house, vacuum thoroughly and make sure you tackle any area where lice might breed, establish a colony and wait for another chance for human contact. The risk of getting infested by a louse that has fallen onto a carpet or furniture is very small, however, you need to be proactive. Head lice survive less than 1–2 days if they fall off a person and cannot feed; nits cannot hatch and usually die within a week if they are not kept at the same temperature as that found close to the scalp.
The number of children per family, the sharing of beds and closets, hair washing habits, local customs and social contacts, healthcare in a particular area (i.e. school) and socioeconomic status are found to be significant factors in head louse infestation. Girls are two to four times more frequently infested than boys due to the length of their hair. Children between 4 and 14 years of age are the most frequently infested group, as it is harder for them to comply with the ‘no-sharing’ policy.
As lice are a becoming a bigger problem because they are starting to develop a tolerance to the products used to get rid of them, most people are going back to home remedies that are safer for children as well. Keep in mind that most lice outbreaks take place during summer time, so be prepared for when the season comes. Should you need further information on how to get rid of a lice infestation, you can also visit our related article.
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