Human lice are tiny insects that live on the body. It differs from lice found on other animals and the species of lice that affect different parts of the body may also vary. Head lice is by far the most common and can affect both adults and children. Pubic lice is another type that is mainly a problem for adults. Although lice infestation is not usually considered to be a serious health problem, the recent rise in drug resistant lice does mean that it is more difficult to treat these days.
Read more on resistant lice.
How to Spot Lice
Lice may cause obvious signs and symptoms to the person who has an infestation. However, this may not be as obvious to others. In fact you may find it difficult to spot a lice infestation on a friend, family member, class mate or work colleague. Furthermore a lice infestation is not entirely a matter of personal hygiene. A person who appears unclean or has a bad body odor is not definitely going to have or carry lice.
On the other hand, good personal hygiene can help reduce the spread of lice. Close contact can easily spread the infestation from one person to another, be it through direct contact or sharing personal items. Therefore lice infestation cannot be entirely prevented just by avoiding contact with a person who has lice. However, prompt and effective treatment will quickly eradicate the infestation.
It is important to note that these is not only one type of louse that affects humans. Different lice species may infesta the head, body or pubic region. Therefore a person who has a lice infestation in one area will not automatically be at risk of an infestation at one part of the body. For example, a person with head lice will not automatically develop a pubic lice infestation and vice versa.
Who gets lice?
Any person who comes in contact with a person with a lice infestation is at risk. According to reports, as many as 12 million American children in the 3 to 11 year age group develop a lice infestation every year. Head lice tends to be more common among children, body lice is more common among homeless people and pubic lice among sexually active teens and adults. Girls are at a greater risk of head lice but this is mainly due to social factors such as close head-to-head contact and sharing personal items.
Read more on how to get rid of lice.
What does lice infestation look like?
A lice infestation is a surface condition meaning that it is isolated to the skin and hair. There are the obvious signs and symptoms like itching, rash, sores and even the insects (lice) and its eggs (nits) may be visible. Less obvious symptoms include sleeplessness and irritability. Some lice can carry bacteria that may cause a heart infection and in these cases there may be heart-related symptoms.
Tickling and Itching
Tickling and itching of the skin over the affected area are some of the more common symptoms. The tickling sensation is due to the movement of the lice on the skin surface, particularly where there is significant hair. Some people will clearly feel the sensation of insects crawling on the skin. The itching is a result of the lice feeding on blood and the subsequent irritation of the bite and allergic reaction to lice saliva.
Eggs and Insects
Both the eggs and insects maybe visible particularly in pubic and head lice. The eggs (nits) can be seen sticking to the hair shaft on the head and pubic region. It appears as tiny white to yellow spots and is often mistaken for dandruff. The insects look like small seeds and may be seen moving around the infested area. It may also be seen on clothing and at times fall onto objects when scratching the affected area vigorously.
Skin Rash and Sores
A skin rash arises with the allergic response to the lice saliva, irritation to the skin surface by the bites and with scratching. It may appear as small red bumps over the infested area. Scratching can cause breaks in the skin and introduce bacteria into the wound. This may result in secondary bacterial infections of the skin where redness, swelling and pain is prominent. There may also be an oozing discharge from the sores in these cases.
Lice may feed at any time but tend to be more active at night. Therefore symptoms like itching tend to be worse at night and this may affect sleep. It may not always lead to a break in sleep cycle but a person will report a poor quality sleep with associated symptoms, such as fatigue, upon waking. Children may also be irritable and show other psychological symptoms due to sleep disturbances.
Hair Loss and Darkening
Sometimes hair is voluntarily removed when treating a head lice infestation. This hair loss is not spontaneous or occurs as part of the infestation. However, in severe and rare cases there may be hair loss as a result of the infestation and particularly with vigorous and persistent scratching. There may also be darkening of the skin usually due to repeated trauma as a result of the itching and subsequent scratching.
Lice and the Heart
Body lice can carry certain bacteria which can then cause an infection of the heart. These bacteria known as Bartonella quintana can lead to infective endocarditis where the inner lining of the heart and the valves are infected. As a result there may be a host of other signs and symptoms beyond the surface of the body. Some of these symptoms include:
- Shortness of breath
- Heart murmur
- Swollen legs and feet
- Persistent cough
There are other signs and symptoms that also need to be considered as part of the infective endocarditis presentation. It is important to note that infective endocarditis can be a very dangerous infection and can lead to serious complications like heart failure or a stroke if the infection is not promptly treated.