Head lice or head louse are small parasites that can only survive in a human host. Lice have six legs with tiny claws at the ends. This allows them to attach themselves to individual strands of hair. The parasites have the ability to stay attached to their human hosts, close to the scalp, where they feed on blood. Lice aren’t dangerous, in the sense that they don’t carry diseases according to the CDC. The bites will cause annoying itching and could potentially lead to an infection.
How Many Eggs Do Lice Lay?
Nits are the name for the eggs hatched by a head louse. An adult female louse will travel to a human’s scalp to lay her eggs and can lay about 3 to 5 eggs each day. When the egg is laid, a sticky substance comes out as well. This sticky substance glues the nit to the human hair giving it the opportunity to hatch on its human host. Nits are tiny and oval-shaped, ut can be identified by their yellowish, off-white color.
After about a week, the eggs hatch and a nymph are born. Nymphs feed on human blood. They need to remain on their human hosts to survive and grow into a full-sized louse. This progression of three growth spurts takes between 9 and 12 days. Although, even a full-grown adult louse is difficult to see, because of the tan, brown color and small size. They are roughly the size of a sesame seed. Like the nymph, the adult louse must stay attached to a human host to survive. On average, an adult louse will live about 30 days when attached to a host but will die within a few days if removed.
The Head Lice Lifecycle
This graphic depicts the life cycle of the head louse across each developmental stage starting with the egg and continuing to 1st nymph, 2nd nymph, 3rd nymph, an adult male or female.
The How Do People Get Head Lice?
Close-up underbelly view of a head louse attached to a human hair.
One commonly asked question is can black people get lice? Absolutely. Black people can get lice just like people from other ethnic origins.
Statistics show that black people tend to be less prone to get infected by the parasite, although I haven’t found any scientific evidence that substantiates the reason behind the data point.
There are some hypotheses that natural hair is more susceptible to head lice than chemically altered hair types or textures, although this theory hasn’t been substantiated.
Since the head louse is an obligate parasite, it can only survive on human hosts. The louse cannot be passed along from pets or other animals to humans. They can only be transmitted from one human host to another (source).
In order for a person to be infected with lice, they need to make contact with another person who is already carrying at least one head louse. There are a few other ways that someone can become infected, but we’ll discuss these less frequent methods later in the article.
Lice are common among children and are sometimes transmitted at school. However, it’s more commonly transmitted where many children are in close head-to-head contact. For example, sleepovers are a common culprit for lice transmission.
While a louse must travel from one host to another to live, they can survive for a few days without being attached to a host. This means that head lice can also be spread by sharing hats, combs, and other belongings.
Where Do Lice Come From?
It should be noted that infestations are not caused by poor hygiene. While there is still a stigma surrounding lice, it is extremely common and easy to treat.
With schools being at high risk of infestations, many have adopted a “no-nit” policy. This means that a child cannot be in the school if they have even a single nit.
While some schools see this as a necessary precaution, some parents and healthcare professionals take issue with the policy.
Those who are against the “no-nit” policy agree that a child should be allowed to go back to school when they begin treatment to eliminate the parasite.
Are Head Lice Dangerous?
The short answer is no, lice are not dangerous. The parasites do not carry diseases and shouldn’t be considered a medical hazard.
The CDC (Centers for Disease Control and Prevention) does not have any regulations for lice infestations, but local health departments will often have guidelines for schools. Consequently, schools are generally very cautious about dealing with infestations of the parasite.
If an individual discovers they have lice, they should treat the problem promptly. The insects cause an annoying itchy feeling and scratching can lead to a skin infection that could become more dangerous.
How Do You Know If You Have Head Lice?
Is it head lice or dandruff? The answer is pretty simple. Lice can be diagnosed when a nymph or adult head louse is found living in the hair.
It can be difficult to find and diagnose infestations because the parasites move quickly and hide within the hair when exposed to light.
It’s most common for the insects to be in the hair around the ears and on the back of the neck.
Signs of the insect include excessive itching, sores on the scalp from scratching, and the feeling of the insects moving throughout the hair.
Nits sticking to the hair shaft can indicate that the hair is infested with live insects, but that isn’t always the case.
When nits are found, the eggs have usually already hatched and turned into nymphs or adult lice which may or may not still be living in the hair.
Going over the hair with a fine-tooth comb and deliberately looking for the parasites is the best way to find them. Nits are often mistaken for other things like dandruff and hairspray.
So, how can you tell if you have lice? It’s best to be diagnosed by a medical professional or someone who is qualified to give a definitive answer.
How to Get Rid of Head Lice: Understanding Your Treatment Options
For as long as head lice have been around, people have been searching for the best method to eliminate the parasite. Everything from mayonnaise to prescription medication has been tested.
Find out what works, what doesn’t work, and what you need to do to keep these parasites out of your home.
While head lice aren’t dangerous, they should be treated immediately. This will help mitigate scratching that could lead to infection and prevent the infestation from spreading to others.
There are many products on the market that can get rid of lice. Your options include over the counter products, natural products, and prescription products.
Natural products for getting rid of head lice often include ingredients like tea tree oil and eucalyptus oil, which many believe can be equally as effective as the chemical ingredients in over the counter and prescription products.
The products, like foams and shampoos, work by killing the living parasites and eggs which can then be removed. If even one living nit is left in the hair, it can lead to another round of insects.
If your child is diagnosed with lice, it’s important to alert the school nurse or your child’s teacher so that other children can be checked and the lice cycle can be ended.
Eliminating lice from the hair and from the home will be a process that will take some time. Whether you choose a natural, over the counter, or prescription treatment option, you may need to go through several cycles of combing, applying products, and shampooing to remove all nits and lice from the hair.
After one cycle, there may be some remaining nits. Following instructions closely will ensure those remaining nits will be removed before they have a chance to hatch. Talk to your health care provider to choose the product you feel most comfortable with using to treat an infestation.
Natural Remedies and Home Remedies for Parasite Infestations
The image above shows a stainless steel nit free comb designed to help people deal with infestations.
If you’re wondering how to get rid of head lice—with its manic itching and other symptoms, start by checking the fridge. Most homes have this sandwich condiment handy, particularly in the summer when picnics and barbecues are popular. Experts recommend spreading mayonnaise over the entire scalp, covering it with a shower cap, and leaving it on overnight in the hopes that the lice will suffocate from the mayonnaise. In the morning, comb hair thoroughly—ideally with a special lice comb (you can buy one at most drug stores) to remove all the dead lice as well as nits, then wash with dish detergent in order to cut through the grease of the mayonnaise. Don’t worry if it takes several piles of washing. These are head lice symptoms that you need to watch out for.
Because some people have coconut allergies, another one of the more promising home remedies for lice involves using petroleum jelly, a household item you no doubt have in a drawer or closet somewhere. One caveat for the use of petroleum jelly, however, is that it is very resistant to cleansers. If you do apply petroleum jelly to the scalp and hair in order to kill lice and nits, it may take several passes with harsh dish detergent in order to remove all of the residues from your hair. Petroleum jelly may be a better option for those with very short hairstyles.
Danielle Fisher MD, FAAP, chair of pediatrics at Providence Saint John’s Health Center in Santa Monica, California, suggests trying tea tree oil as one of the home remedies for lice because it has powerful antiseptic properties. Use it in the same manner as mayonnaise. “The idea is the same,” she says, “To smother the lice and nits, and they die and can be removed.” Dr. Fisher warns, however, that there are mixed recommendations for how long to keep the oil on the head, and how often to repeat. Many recommend two or three treatments per week until there are no more lice or nits found when combing.
When you realize that your child has head lice you may have to choose between a traditional OTC lice treatment and several home remedies for head lice. Among them, olive oil is one of the most effective and simple ways to get rid of these parasites.
The olive tree has exceptional therapeutic properties. In fact, all parts of the tree possess interesting properties for medical use. Our ancestors in ancient Greece used olive oil as an ointment to treat aches, ulcers and even cholera.
They used the leaves of the olive tree as a base, astringent and purifying, as well as preparations made from leaves and olive oil to cure all kinds of inflammations. Moreover, the flowers, bark, and ash of the olive tree were included in many medicinal preparations.
Several informal studies showed the effectiveness of vegetable oils in the treatment of lice. A test (not a study) conducted by the Harvard School of Public Health found that lice submerged in olive oil for two hours die asphyxiated.
Other studies have shown that it takes more than 8 hours to suffocate the lice with a substance such as olive oil. The effectiveness of olive oil is explained by the fact that by coating the skin of adult lice, it deprives them of oxygen. After some time, as they can no longer breathe, they die.
Although lice are not actually vampires, using this ancient remedy against the undead can also get rid of a lice infestation. Garlic is one of the home remedies for lice that is a terribly smelly option but make a paste with 8 to 10 garlic cloves and a few teaspoons of lime juice. Spread on the scalp and leave the paste on for a half an hour. Shampoo to clean. The intense smell is believed to kill the live lice and their nits. This treatment should be repeated weekly for one or two months.
These are popular home remedies among those looking for a natural solution to eliminating lice. The success rate of several of these home remedies is questionable. Actually, some of these home remedies simply do not work.
Users expect these home remedies to suffocate the parasites, killing the existing nymphs and lice and not allowing the eggs to hatch. We don’t recommend using home remedies to treat head lice since many of them simply don’t work, but definitely understand why many people go with this option.
To use one of these natural remedies, start by using a fine-tooth comb to remove as many of the eggs and insects as possible. Then, coat the hair in one of the aforementioned substances.
Because these insects can survive without breathing for up to eight hours, it’s recommended that the hair remains coated and a shower cap be worn overnight in order to suffocate and kill the lice.
After letting the substance sit overnight, wash thoroughly with regular shampoo before combing again to remove what’s left of the nits and lice.
Many parents choose these natural home remedies in order to avoid using harsh chemicals on children. While the intentions behind the choice are great, home remedies may not always be effective.
The ability of these insects to survive without fresh air means that smothering won’t always kill all of the lice. While the process can be repeated daily, if any nits aren’t killed and removed from the hair, the parasites will continue to come back.
Treat the lice with essential oils
According to Healthline, A number of essential oils have been shown to be effective — along with combing — in eliminating head lice.
Essential oils are never ingested. In fact, some are toxic. Before you use any essential oil, always dilute them with a carrier oil and put a small drop of the diluted mixture on the back of your child’s hand. If there is no reaction, the essential oil should be safe to use.
There isn’t enough research to be sure that essential oils are safe for children.
Though pretty rare, some kids have allergic reactions to these oils — usually tea tree oil. If your child is allergic to one, move on to the next oil on the list. The oils that have shown effectiveness are:
- tea tree oil
- lavender oil
- neem oil
- clove oil
- eucalyptus oil
- aniseed oil
- cinnamon leaf oil
- red thyme oil
- peppermint oil
- nutmeg oil
Mix 2 ounces of olive oil with 15 to 20 drops of the essential oil. Apply this mixture to the scalp using cotton balls. Leave it on the scalp and hair overnight — at least 12 hours. Comb out and shampoo, rinse, and repeat.
An alternative approach is to mix the 15 to 20 drops of essential oil in 4 ounces of rubbing alcohol. Place the mixture in a spray bottle and saturate the hair with it. Again, leave it on for at least 12 hours. Once the lice have been eliminated, the alcohol spray can be used as a preventive treatment.
Remember — combing out the hair is absolutely essential to remove the lice and their eggs
Treating Infestations with Over the Counter and Prescription Medications
There are several reliable over the counter and prescription elimination products on the market. These products work in a variety of ways, but most serve to paralyze and kill the parasites quickly and effectively.
As with natural remedies, these products will also require combing before and after use. Start by combing the hair and removing as many eggs as possible. Then, follow the instructions on the product you choose.
Each product will have unique instructions for applying the substance, the amount of time the product should sit on the hair, how the hair should be cleaned afterward, and how frequently the product should be used to ensure that the hair won’t become infected again.
While over the counter and prescription medications for lice treatment are safe for use, it’s important to follow the instructions exactly and to only use the recommended amount of the product as directed.
If it’s clear that the product isn’t working after 2 to 3 applications, the lice may have a resistance to the medication. If this is the case, consult a medical professional to determine your next step.
With over the counter or prescription medication lice treatments, there is a chance of an allergic reaction. Some products may cause itching, soreness, or redness.
If you notice any type of reaction to a product, stop using that product immediately and consult a medical professional before continuing treatment or tying out another treatment option.
Eliminating the Parasite from Your Home
In addition to killing the lice living in the hair, it’s important to address the lice that may have found their way into your home. While lice need to have a human host in order to live, they can survive away from a host for a couple of days before dying.
Clothing, hats, scarves, plush toys, bedding, and towels should be machine washed and dried on the highest heat setting. The heat, anything higher than 128.3 degrees, will kill the lice within five minutes of exposure.
Those items that can’t be cleaned in a washing machine and dryer can be sealed in a plastic bag. While the lice can’t survive for more than a couple of days, it’s recommended that the items remain sealed for up to two weeks.
Don’t forget to soak any combs, brushes, and hair clips that you may have used in hot water for at least five minutes. It’s natural to have the desire to clean the house top to bottom when dealing with a lice infestation. Generally, a routine house cleaning is sufficient for eliminating lice from the home.
Be sure to vacuum carpets and any fabric-covered items in the home. Fumigant sprays are not only unnecessary but discouraged, as they can be harmful if inhaled or absorbed through the skin.
As you clean the home, remember that lice can only survive if attached to a human host. Only those items and surfaces that have made contact with the infected person’s hair will need to be cleaned. Human lice cannot survive on pets and pets do not need to be treated for human lice.
Understanding Everything About Malathion
Malathion, otherwise known as ovide lotion, is a prescribed drug that was approved for sale by the FDA (U.S. Food and Drug Administration), for treating head lice.
Malathion lotion was approved for treating head lice and is effective and safe when it is used as directed. Malathion lotion is both ovicidal (kills a portion of lice eggs), and pediculicidal (kills the live lice).
What are the Steps for Using Malathion?
Step 1 – Treating the Person Infected with Head Lice
Always be sure that you follow the pharmacist’s or physician’s detailed instructions and make certain to read the label on the bottle of malathion.
Carefully begin to apply the malathion to dry hair. Continue to do so until the hair and scalp are thoroughly coated and wet. Be sure to use the malathion behind the ears and on the back of the neck and head too.
According to the manufacturer’s recommendations, malathion should be left on uncovered hair for between eight and twelve hours.
During this time it is important to let the hair dry naturally, never use a hairdryer or other electric heat source on the treated areas.
While the hair is wet, never use a blow dryer, flat iron, curling iron, or styling stick. Once the head has been treated, make sure that the person changes into clean clothing.
The best time to apply the treatment is before bedtime to avoid having to reapply. Be sure to cover the pillow thoroughly with a clean towel to keep that medication from staining any bedding materials.
Once the eight to twelve-hour time period has elapsed, begin thoroughly shampooing the scalp and hair.
Begin to rinse the malathion and shampoo from the hair and make use of a fine-toothed nit comb. This type of comb will easily remove any of the dead nits and lice from the hair.
Every two to three days you should use the fine comb to check the hair for any signs of lice. Part the hair and carefully check the scalp, looking for live lice or eggs. Continue checking the hair for two weeks to make certain that all the parasites are gone. If any live lice are discovered during this time, retreat with another application with the malathion as instructed on the product’s label.
Important Warnings and Precautions about Malathion
The malathion is a powerful medication that can cause stinging of the scalp if there are open sores from scratching the lice. Avoid contact of the malathion with the eyes. Rinse your eyes immediately with cold water if contact occurs.
Keep the malathion away from heat sources like open flames, blow dryers, and flat irons, because it is flammable.
If you are pregnant, consult with your physician before using the medication.
Step 2 – Home Treatments Plus Additional Measures
If the parasites fall off the head, they are unable to feed and will die within a few days. The nits will not be able to hatch and usually die within the week if they aren’t kept at the same temperature that was on the scalp.
There is no need to spend a huge amount of time on house cleaning activities because any fallen lice and nits will be dead in days. The following steps can help avoid any re-infestation of the nits or live lice that could have fallen into clothing or furniture.
To effectively kill off the nits and live lice that could have crawled from the head to clothing during the application of the malathion, machine washes the bed linens, pillowcases, clothing, towels, stuffed animals, blankets, that the infected person came in contact with.
Make sure to wash in hot water and then dry on the highest heat setting available in your dryer. Items that can not be washed should be taken to the cleaners immediately.
Another good option is to place any infected items in a strong sealable plastic bag that can be properly sealed. Leave the items in the bag for two weeks. Soak any brushes and combs in hot water for approximately ten minutes.
Vacuum the floors, the upholstery, furniture, area rugs, or any area the infected person was sitting.
Although the risk of getting infected by lice that have fallen off the head is extremely unlikely, it is better to be safe. Avoid trying to fumigate the rooms or the house because those sprays can be highly toxic if absorbed through the skin or inhaled.
Step 3 – Preventing Re-Infestation of Head Lice
The most common way that the head lice are spread is from direct hair-to-hair or head-to-head contact. It is less common that the parasites can be spread by way of sharing belongings or clothing. Once the lice or nits have fallen off the head, they will die quickly unless they land on another person’s head immediately.
Teaching children to avoid certain types of play can lessen the chances of them getting infected by head lice.
Teach your kids to avoid head-to-head contact during activities at school, slumber parties, playgrounds, camp, and sporting activities.
Never allow children to share clothing like hats, caps, coats, scarves, sports uniforms and hair ribbons. Also don’t let children share brushes, combs, and towels.
Last but not least, don’t allow the child to lie on any bed, couch, carpet, pillow, stuffed animal, that was recently in contact with someone infected with head lice.
Frequently Asked Questions
My child is six years old and was sent home with head lice. Can I use the malathion lotion to treat their condition?
Before you treat any child for head lice, always ask their pediatrician for recommendations. The effectiveness and safety of the malathion have not yet been established in children under the age of six years old.
Are treatment failures common with malathion?
No, although re-infestation of the lice can occur, though.
Are the second treatments needed?
Possibly. If live lice and nits are still being found after seven days, the second treatment of malathion is recommended. During this time other family members should be checked for head lice infestation.
Does the malathion kill lice eggs?
Answer: Yes. The malathion available by prescription in the United States will kill lice eggs.
Do lice like clean or dirty hair?
A popular misconception is that head lice are attracted to “dirty” hair. In reality, the spread of lice is not affected by personal hygiene and the cleanliness of a person’s hair or environment. The infestation is mostly spread through direct contact with an infected person’s hair. For children, this can happen while they’re at play with lice-infested kids, at school, at their homes, or any other environment where there is a chance for contact (like sleepovers, camps, and gyms).
How many infestations occur each year?
To my knowledge, there is no accurate data available regarding the number of head lice infestations that occur in the United States every year.
However, we do have data about the children aged three to eleven years who do get infested each year. The number is estimated to be around six to twelve million infestations every year for this particular age group.
Girls seem to be more vulnerable to getting infected than boys, probably due to having longer hair and more hair-to-hair contact.
Another interesting piece of data is regarding infestations in black people. Head lice infestations are less common among black people or African Americans compared to those of other races. Scientific research explaining the reasons are nonexistent to my knowledge, but I will continue to update this article when a comprehensive scientific study is released. However, just to make sure that you completely understand, black people can definitely get head lice. Also, black people should follow the same treatment advice outlined in this article.
What are the common head lice symptoms? Do head lice carry diseases?
A head louse has no capacity to carry disease (according to the CDC) and is not considered a major health hazard.
Some head lice infestations are asymptomatic (i.e. symptoms are not obvious). However, most cases are characterized by extreme itching (known medically as “pruritus”) that is caused by a person having an allergic reaction to lice bites. The itching can occur four to six weeks after a person gets infected.
Aside from the itching, there are also other symptoms that people need to watch out for. These include having a sensation or lingering feeling that there is something crawling through your hair. Also, sores on the head caused by incessant scratching are common symptoms. Sometimes these sores may get infected if the skin breaks.