Head Lice: Causes, Symptoms, Transmission, Risk Factors

Head lice are tiny insects that feed on a person's scalp blood. Typically, head lice affect children. The insects usually spread straight from one person's hair to another.

Having head lice is not a sign of poor personal hygiene or unclean living conditions. There are no viruses or bacteria spread by head lice.

Head lice can be treated with prescription and over-the-counter medications. Take great care to adhere to the treatment suggestions to eliminate lice and their eggs from the scalp and hair.

People also use a range of natural or at-home remedies to get rid of head lice. Nevertheless, there is little to no clinical evidence supporting their effectiveness.

Causes Of  Head Lice

A head louse is a brown or greyish insect about the size of a strawberry seed. It feeds on the scalp blood of humans. The base of a hair shaft is where each egg is firmly connected by the sticky substance generated by the female louse, less than 1/4 inch (5 mm) from the scalp.

The life cycle of Louse

For a louse, there are three stages:

• It takes six to nine days for the eggs to hatch.
• The juvenile, immature stages of the louse are called nymphs, and they take nine to twelve days to evolve into adults.
• Adult lice have a three- to four-week life cycle. The female louse lays six to ten eggs each day.

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Symptoms Of Head Lice

The following symptoms are often present in head lice cases:

• Itching: Ear, neck, and scalp scratching is the most common symptom of head lice. This is an allergic reaction to flea bites. When someone catches head lice for the first time, it can take four to six weeks for the itching to begin.
• Lice on the scalp: Lice can be observed, but because of their small size, ability to avoid light and fast movement, they are usually hard to detect.
• On nits, lice eggs, or hair shafts: Since nits stick to hair shafts, it might be challenging to identify them due to their small size. 
• The most common areas to see are the areas around the ears and the hairline of the neck. Empty nits may be easier to spot since they are lighter in colour and are farther away from the scalp. However, the presence of nits does not necessarily mean that live lice are present.
• Sores on the scalp, neck, and shoulders: Scratching may cause small, red lumps that could occasionally become infected with bacteria.

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Transmission Of Head Lice

While they can crawl, head lice cannot jump or fly. Direct head-to-head contact, which can happen within a family or between children who play or go to school together frequently, is the usual way that head lice spreads.

It is less typical for head lice to spread by indirect touch. Nonetheless, the insects can spread from one person to another through personal items such as:

• Hats and scarves
• Brushes and combs
• Hair accessories
• Headphones
• Pillows, upholstery, and towels
• Head lice may spread more easily when clothes are piled together. Scarves and hats, for example, can transmit lice if they are stored in the same school locker or hanging from the same hook.
• Household pets such as dogs and cats do not aid in the spread of head lice.

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Risk Factors Of  Head Lice

Direct head-to-head contact is the primary method by which head lice are transmitted. Consequently, the greatest risk of head lice transmission occurs amongst youngsters who play or go to school together. The presence of head lice primarily affect children in preschool and elementary school in the United States.

Diagnosis Of  Head Lice

The American Academy of Paediatrics recommends that the best way to diagnose head lice is to find a live nymph or adult lice.

Wet hair lubricated with a hair conditioner or another substance has to be inspected, according to the guidelines. Your child's physician will carefully comb their hair, from the scalp to the tips, with a fine-toothed comb also called a "nit comb." If no live louse is found, the doctor will likely perform the entire check again during the second appointment.

The doctor who sees your child will also examine their hair for nits. To find nits, the person caring for your child may use a Wood's light, a unique type of light that gives the appearance of bluish dots on the skin. Nevertheless, the existence of nits does not always imply the presence of live lice.

A live nit has to be near the scalp to survive. If nits are located more than 1/4 inch (6 mm) from the scalp, they are most likely dead or empty. If it's thought that the suspect nits are alive, a microscope can be used to examine them.

Treatment Of  Head Lice

If the healthcare professional discovers no living nits, the lice were probably carried over from a previous infestation and don't need to be treated.

Lice in some locations have developed resistance to over-the-counter medications. Treatment failure can also result from improper use of over-the-counter medications, such as missing doses or failing to return to appointments on time.

If the appropriate use of a nonprescription treatment has not proven effective, your healthcare provider may recommend a prescription medicine. Among them are:

Spinosad Natroba. Spinosad is safe for usage by adults and toddlers six months of age and up. It can be applied to dry hair and rinsed with warm water after ten minutes. It destroys lice and nits and usually doesn't require any further treatments.

Your doctor might recommend an over-the-counter medication that eradicates lice and certain types of mites. These medications might not damage recently implanted eggs. Therefore, a second treatment given at the appropriate time is frequently needed to eliminate nymphs after they hatch but before they become adult lice.

Many re-treatment plans are available; however, some research suggests that the optimal window for a second treatment is seven to nine days after the first. Ask your healthcare provider for specific advice on a recommended course of treatment.

The following pharmaceuticals are available without a prescription:

• Permethrin: Permethrin is produced by synthesizing pyrethrin, a chemical component extracted from chrysanthemum flowers. Perchlorin poisoning affects lice. Before applying permethrin, wash your child's hair with shampoo, not conditioner. Rinsing the hair with white vinegar before washing can help break the glue that binds nits to hair shafts.
  • Leave the medication in your hair for the recommended amount of time, as instructed on the packaging. After that, rinse your child's hair over a washbasin with warm water. Permethrin does not kill nits, thus treatment needs to be repeated nine or ten days after the first application. Irritation of the scalp and redness are potential adverse effects.
• Ivermectin- Ivermectin is harmed by lice: The lotion is safe for use by adults and children six months of age and up. It can be applied once to dry hair and then washed out with water. Before applying permethrin, wash your child's hair with shampoo, not conditioner. Rinsing the hair with white vinegar before washing can help break the glue that binds nits to hair shafts. Leave the medication in your hair for the recommended amount of time, as instructed on the packaging. After that, rinse your child's hair over a washbasin with warm water.

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Prevention Of  Head Lice

Due to the close contact that children have at daycare centres and schools, it is challenging to stop the spread of head lice.

There is very little chance of private information being indirectly disclosed. However, you can teach your child how to: stop head lice from spreading

• Separate clothes and hang them on various hooks from other kids' clothes.
• Never share scarves, combs, brushes, or hats.
• Refrain from resting on sofas, beds, or pillows that have recently been in contact with a head lice carrier.
• Whether sharing is respected, it's not necessary to refrain from sharing protective headgear whether playing sports or riding.

Complications Of  Head Lice

 If your child scratches their head lice-causing itchy scalp, the skin may crack and become infected.

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