A boil is a skin infection that starts in a hair follicle or oil gland. At first, the skin turns red in the area of the infection, and a tender lump develops. After four to seven days, the lump starts turning white as pus collects under the skin.

The most common places for boils to appear are on the face, neck, armpits, shoulders, and buttocks. When one forms on the eyelid, it is called a sty.

If several boils appear in a group, this is a more serious type of infection called a carbuncle.
Causes of Boils

Most boils are caused by a germ (staphylococcal bacteria). This germ enters the body through tiny nicks or cuts in the skin or can travel

These health problems make people more susceptible to skin infections:

Diabetes
Problems with the immune system
Poor nutrition
Poor hygiene
Exposure to harsh chemicals that irritate the skin

Symptoms of Boils

A boil starts as a hard, red, painful lump usually about half an inch in size. Over the next few days, the lump becomes softer, larger, and more painful. Soon a pocket of pus forms on the top of the boil.

These are the signs of a severe infection:

The skin around the boil becomes infected. It turns red, painful, warm, and swollen.
More boils may appear around the original one.
A fever may develop.
Lymph nodes may become swollen.

When to Seek Medical Care

You start running a fever.
You have swollen lymph nodes.
The skin around the boil turns red or red streaks appear.
The pain becomes severe.
The boil does not drain.
A second boil appears.

You have a heart murmur, diabetes, any problem with your immune system, or use immune suppressing drugs (for example, corticosteroids or chemotherapy) and you develop a boil.
Boils usually do not need immediate emergency attention. However, if you are in poor health and you develop high fever and chills along with the infection, a trip to a hospital's emergency room is needed.

Boils Treatment -- Home Remedies

Apply warm compresses and soak the boil in warm water. This will decrease the pain and help draw the pus to the surface. Once the boil comes to a head, it will burst with repeated soakings. This usually occurs within 10 days of its appearance. You can make a warm compress by soaking a wash cloth in warm water and squeezing out the excess moisture.
When the boil starts draining, wash it with an antibacterial soap until all the pus is gone and clean with rubbing alcohol. Apply a medicated ointment (topical antibiotic) and a bandage. Continue to wash the infected area two to three times a day and to use warm compresses until the wound heals.
Do not pop the boil with a needle. This could make the infection worse.

source: http://tradot.com/blog/post?BrightMekaBlog_Causes-symptoms-Prevention-and-treatment-of-boils-142a