Facebook Twitter LinkedIn Syndicate. Minus Related Pages. Causal Agent: Pediculus humanus capitis , the head louse, is an insect of the order Psocodea and is an ectoparasite whose only host are humans. Life Cycle: The life cycle of the head louse has three stages: egg, nymph, and adult.
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These look like tiny yellow, tan, or brown dots before they hatch. Lice lay nits on hair shafts close to the scalp, where the temperature is perfect for keeping warm until they hatch. Nits look a bit like dandruff, but aren't removed by brushing or shaking them off. Unless a child has many head lice, it's more common to see nits in the hair than live lice crawling on the scalp. Lice eggs hatch 1—2 weeks after they're laid.
After hatching, the remaining shell looks white or clear and stays attached to the hair shaft. This is when it's easiest to spot them, as the hair is growing longer and the egg shell is moving away from the scalp. Adult lice and nymphs baby lice. Adult lice are no bigger than a sesame seed and are grayish-white or tan. Nymphs are smaller and become adult lice about 1—2 weeks after they hatch. This life cycle repeats itself about every 3 weeks. Most lice feed on blood several times a day, and they can survive up to 2 days off the scalp.
With lice bites come itching and scratching. This is due to a reaction to the saliva spit of lice. But the itching doesn't always start right away. It depends on how sensitive a child's skin is to the lice. It might take weeks for kids with lice to start scratching.
They may complain, though, of things tickling or moving around on their heads. Small red bumps or sores from scratching. Some kids have mild irritation from scratching, while others may get a bothersome rash. Scratching a lot can lead to a bacterial infection.
Watch for swollen lymph nodes glands on the back or front of the neck, and red, tender skin that might have crusting and oozing. Doctors can treat a skin infection with an antibiotic. How Are Head Lice Treated? The two main ways to treat lice are: medicine removing by hand Medicine: Medicated shampoos, cream rinses, and lotions are available that kill lice.
Are Head Lice Contagious? Pets can't catch head lice and pass them on to people or the other way around. Can We Prevent Head Lice?
Four out of five infested individuals will not feel an itching sensation from a head lice infestation. Female head lice live about 30 days while males live about 15 days. Vinegar has no effect on getting rid of head lice. Only several weeks after infestation does one feel an itching sensation. Head lice mate only once in their life.
The female head louse can lay between eggs per day. On average an infestation is diagnosed after 4 weeks. Head lice are basically helpless and unable to move on a smooth surface. Head lice have more than one dozen breathing openings. Head lice can live no longer than 55 hours without human blood. Poor bathing habits encourage lice infestations. Head lice can spread disease.
Head lice are commonly transmitted from a theater seat. Head lice drown while the host is swimming. Dogs and cats can spread head lice. Once you have killed all the hatched lice you are cured. Topical anti-lice shampoos are effective at killing lice eggs. Where do head lice come from? They would never chose to come off of a head and onto a pillow, hat, chair, etc Who can get head lice? How are head lice spread? What are the Symptoms of Head Lice? What do head lice and their eggs look like?
Do head lice jump? Do head lice carry or transmit any disease? What can be done to get rid of head lice and the eggs? What is the life cycle of head lice and their eggs? Eggs: Eggs are laid by adult female lice and usually take about a week to hatch into nymphs. What is the difference between an egg and a nit?
How can I tell if the nits are dead or alive? Are children the only ones who get head lice? Do pets get head lice? Head lice cannot live on pets. Head lice can only live on human heads. Experts used to suggest bagging items such as stuffed animals for a number of weeks to help bring infestations under control. Since lice cannot survive without human blood, this is unnecessary; vacuuming is a sufficient safeguard for any questionable areas or items that may be in contact with those who are infested.
You can also put bed linens, stuffed animals and other items in a dryer for 30 minutes. Save your physical and emotional energies for screening and thorough lice and nit removal. Head lice can be spread whenever there is direct contact of the head or hair with an infested individual.
Lice can also be spread through the sharing of personal articles like hats, towels, brushes, helmets, hair ties, etc. There is also a possibility of spreading head lice via a pillow, headrest or similar items.
Head lice do not jump or fly and generally cannot survive longer than 24 hours off the host. If a louse comes off the head and is left behind i. Vacuuming is recommended for any areas or items that may be in contact with those who are infested. Swimming with someone who has lice carries no greater risk of transmission than any other activity. When lice are in water, they go into a state of suspended animation but remain firmly locked onto the hair — literally hanging on for dear life.
This is how they survive shampooing, rain, seawater and swimming pools. Risk of transmission will occur with the sharing of towels, piling clothing or towels, storing personal items in close proximity or direct head to head contact. The extent to which head lice are transmitted to others via headphones or helmets is unknown. Ideally, risk of transmission can be eliminated by making sure children have and use their own equipment.
If this is not possible, you can clean the items between children by wiping them with a damp paper towel. An additional measure would be to encourage each child to wear a baseball cap to help shield the hair from contact with the item. Helmets and headphone should never be sprayed.
Most importantly — and best for the entire community — all parents should screen their children regularly. Children, like adults, do not want nits in their hair — dead or alive. The time it would take to make the distinction is time far better spent removing ALL the nits. Finding 10 dead nits guarantees nothing for the 11th.
Head lice do not come out of the air or from the ground. They are human parasites and have probably been here since the beginning of time. Desiccated dried up head lice and their eggs nits have been found on the hair and scalps of Egyptian mummies. While many have thought head lice to be only a nuisance, recent scientific study refutes this notion.
DNA technology shows head lice to be the same species as the notorious body louse which has long been associated with diseases such as typhus and relapsing fever.
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