Pediculosis is a human parasitic infection that has been widespread and known for thousands of years. Lice are bloodsucking insects (which feed on blood), of which only three species out of the over 4000 listed are human parasites.
Definition of pediculosis
Pediculosis means an infestation with lice in humans. There are three types of pediculosis: pediculosis of the scalp, which mainly affects children, body pediculosis, and a sign of health precariousness and the vector of infectious diseases, and finally pubic pediculosis or “lice”.
The causes of pediculosis
The three exclusive lice of man are called pediculus humanus, we distinguish:
- Pediculus humanus variety capitis, responsible for head lice or head lice. This attack of the scalp is experiencing resurgence in recent years.
- Pediculus humanus variety corporis giving body lice, which were very common during the First World War and are now seen in a precarious situation (homeless, migrants …).
- Phtirus pubis, responsible for pubic phthiriasis, colonization by “pubic hair”, which is most often to be considered a sexually transmitted disease.
Who is most often affected?
The pediculosis of the scalp, especially affects children when they frequent the communities (schools, crèches, holiday centers …).
Body lice are mainly found in people living in precarious conditions (lice are found in rarely washed clothes).
Pubic phthiriasis is especially seen in people with multiple sexual partners.
Evolution and possible complications
Pediculosis tends to be infected by scratching.
In body pediculosis, body lice can inoculate bacteria (Bartonella quintana giving trench fever, Rickettsia prowazeckii causing exanthematous typhus and Borrelia recurrentis responsible for recurrent fever).
In cases of pubic phtiriasis, often sexual contamination must search for other sexually transmitted diseases (HIV, herpes, syphilis, chlamydia …).
Symptoms of pediculosis
All pediculosis have itching in common. The seat varies according to the louse involved:
Pediculosis of the scalp causes itching of the scalp and pimples located most often in the neck (the hottest place, where the lice come to bite to suck the blood)
Body lice cause predominant itching in the folds (axillary, inguinal …) and itchy pimples
Pubic phtiriase causes itching of the pubis, even pimples.
Pediculosis of the scalp is common in children in communities (schools, crèches, holiday centers …). Risk factors are unattached long hair, beanies, caps, scarves, close contacts and games between children
Body lice are found in rarely washed clothes. They are therefore frequent in case of precariousness, purchase of second-hand clothing and unwashed second-hand clothes.
Pubic phthiriasis is especially seen in people with multiple sexual partners, with or without a condom. Hair removal of the pubis is a protective factor for phthiriasis (while it favors other sexually transmitted diseases such as herpes, molluscum contagiosums …) because the pubic louse needs hair to move and lay.
The opinion of experts
The pediculosis most often encountered is that of the scalp. Parents are often confused by their children’s recidivism. Here are the causes of treatment failure that must be addressed:
- Lack of treatment of community classmates (class, nursery, etc.) who are therefore still contaminants and spread the disease back to the community. The cause is sometimes the cost of treatment.
- Treatment poorly done: no disinfection of textiles, too short a product application time, too little product applied, product imperfectly lenticidal or resistant, no new treatment 8 days after the first.
It is therefore often necessary to repeat step by step the course of treatment to see what has been lacking and not hesitate to change product because there is often resistance.
Treatment and prevention
The pediculosis of the scalp is partly prevented by the eviction of exchange of cap, cap, scarf, helmet … and wearing short hair or tied if they are long: the lice do not jump but go hair in hair in close contact, the longer one has the long hair the more one risks being contaminated.
The pediculosis of the body can be partly prevented by the washing of used clothes before their fitting.
Pubic phthiriasis is partially prevented by the complete depilation of sex and pubis (the “crabs” cannot cling from one person to another if there is no hair).
The treatments used must have pediculicidal and lenticidal activity. They are not reimbursed by Social Security.
Pediculosis of the scalp
The product can be a lotion insecticide (Malathion, Prioderm to avoid before two years, pyrethrins: Para , Spray Pax …), often more effective than shampoos, or an asphyxiating product (dimeticone, such as Pouxit or Apaisyl ).
The lotion must be applied line by line, in sufficient quantity to wet the whole scalp. It stays in place for a few minutes to a few hours depending on the lotion used. It must follow the instructions for use provided, and then the product is most often rinsed with a non-treating shampoo.
The hair is then combed for the lenght.
It is also necessary to decontaminate combs, brushes, hats, hats, scarves, soft toys, bedding with a contact insecticide or by simply washing at 60 ° C in the machine.
For pediculosis of the body, the disinfection of linen and bedding is usually sufficient by washing at 60 ° C. Non-washable textiles at 60 ° C must be insulated in a plastic bag for at least 3 days. The patient should take a shower with soap to eliminate any lice present on the skin and hair. The shaving of the hairs is necessary in case of abundant nits.
Treat sexual partners and seek concomitant STIs
On the eyelashes, it is possible to apply a cream containing 1% permethrin or in the absence of pure petrolatum.
The pediculosis of the pubis is treated with the same products as that of the scalp, by a lotion insecticide (Malathion, Prioderm to avoid before two years, pyrethrins: Para, Spray Pax …). It is best to treat all the hairy areas of the trunk and thighs but not the scalp. Hair shaving is sometimes necessary in case of heavy nits and mowers, razors, scissors, etc. must be removed by soaking them in water at more than 65 ° C for at least 10 minutes. Clothing that has been in contact with the infested area of the person for 3 days prior to treatment is disinfected by washing at 60 ° C. Non washable textiles at 60 ° C must be insulated in a plastic bag for at least 3 days
Pyrethrins are a group of substances with insecticidal properties, derived from Dalmatian pyrethrum flowers or certain chrysanthemums, in particular the Persian chrysanthemum (Tanacetum coccineum). They are marketed in pharmacy under the trade names Para , Spray Pax …
To prove: coconut oil
Coconut oil has an asphyxiating effect but only dimeticone has been the subject of scientific studies proving its asphyxiating effect in the management of pediculosis