Boil; skin; germ; carbuncle; staph; abscess; staphlococcus; cellulitis; golden staph; pimple; septicaemia; MRSA; staphylococci; aureus ;
Boils are infections just under the top layer of the skin. They cause a tender lump which may 'point' (come to a head) and release pus. Boils often form in the glands around the root of a hair. The wall of the gland keeps the infection in one place, so it does not spread into the surrounding skin.
What are boils?
- A boil is a type of abscess. Abscesses are infections that are walled off so that they do not spread (until they are very advanced). For example an abscess can form inside the appendix, around the root of a tooth, or inside the middle ear.
- The germs that cause boils are germs that live normally on the skin without causing problems. A common cause of boils is a bacterium called Staphylococcus aureus.
- This germ, and others, can cause a different type of skin infection which spreads more easily than boils because there is not a 'wall' around it. This type of infection is called cellulitis.
- The infection starts first in a few cells of the skin. The damage caused to these cells releases chemicals into the blood and surrounding cells, causing blood flow to the area to increase, other cells to swell, and white blood cells (which fight infection) to move to the infected area.
- This causes redness, swelling and tenderness. The infected area also becomes hotter than the surrounding area.
- Pus forms in the middle of the boil when white blood cells gather and work to kill the germs.
- There can be several results from this:
- It 'goes away' - the white blood cells and the rest of the immune system successfully kill the germs, the swelling and tenderness settle down and the boil goes away. A small lump may be there for several days or longer, but no treatment is needed.
- It drains - the amount of pus (dead white blood cells, germs and other tissue) is too big for the body to absorb, so is pushed out through the surface of the skin. The boil 'points' (comes to a head) or develops a white tip, which breaks and the pus escapes. Once the pus drains out of the boil, it usually heals without any further treatment. It may leave a scar.
- It spreads. The pus is pushed out into the surrounding tissue, spreading further in the skin, causing a more serious infection (cellulitis).
- Germs from the boil can 'escape' into the blood, causing a wide spread infection (septicaemia).
- Boils that form in parts of the skin that are quite tight (such as on the back of the neck) may form a type of boil that 'drains' out of several places. This sort of boil is called a carbuncle.
What to do
Most boils either go away or the pus is pushed out (by the body's reaction) and the infection is defeated by the body's own immune system.
- Do not try to squeeze the contents out of a boil because pus is likely to be squeezed into the surrounding skin and can cause a much more serious infection.
- Boils are usually painful. Something warm placed on the boil can help (such as a hot wet face-washer), plus paracetamol.
- Sometimes a boil needs to be 'lanced' (cut open) when the pus does not come out. The skin over the boil is cut, often with a small pointed knife (scalpel) which used to be called a 'lancet'. This should only be done when it is clear that a lot of pus has formed (early on there can be a lump but no pus), and with a sterile blade. Do not try this yourself. See your doctor or health worker if you think this needs to be done.
- There are many thick pastes or ointments that people apply to a boil to help with pain and to 'draw' out the pus. These may be helpful, but make sure they are not too hot (or they could burn) or that they don't damage the skin.
- The pus from a boil will have germs in it, and it can pass infection on to others, so dispose of any dressings carefully (place them in a plastic bag, then into the rubbish bin).
- Generally antibiotics are not needed to treat boils, however antibiotic treatment may be needed if:
- the person starts to feel unwell
- there are signs that the infection is spreading, eg redness spreads to surrounding skin, or starts to spread up the arm or leg
- lymph glands nearby start to swell.
Getting boils often
- Some people seem to get boils often, while others get them rarely if at all.
- If boils keep coming back it could be worth discussing with your doctor whether you have any health problem which makes you more likely to have infections (diabetes for example, or perhaps some immune disorder).
- Keeping clean seems to be important. Washing regularly with a soap that can kill germs may help. Make sure that the skin is dry after washing, and keep it as dry as possible (synthetic material such as nylon in clothes may keep skin moist).
- Make sure that your child does not have any other skin problem such as scabies which can cause scratching and skin infections.
- A good diet, adequate rest and a 'healthy' lifestyle are probably important, but some people seem to get boils even if they do everything 'right' and others don't get them even if they are not so careful.
Stopping the spread
- The pus from boils is infectious, so wash hands and the skin after touching a weeping boil, cover it with a waterproof dressing and dispose of dressings carefully so that others do not get the germs.
- If the boil drains and the pus gets onto towels or sheets wash them with detergent in hot water and dry them in the sun or hot air clothes drier. Ironing will also kill all the germs.
- Handwashing is also very important.
- Staphylococcus aureus is a bacterium (germ) which is also known as 'golden staph'.
- About 10% of people carry Staph aureus on their skin, and for most this does not cause any infection.
- Occasionally Staph aureus causes skin infections (eg school sores [impetigo] and boils) and rarely more serious infections.
- Staph aureus can get into food when hands are not properly washed, and can cause food poisoning.
- Most Staph aureus can be killed by antibiotics, but some are resistant to most of the commonly used antibiotics. These bacteria are called MRSA (methicillin resistant Staph aureus).
- MRSA do not cause more serious infections that other Staph aureus, but if antibiotic treatment is needed, special antibiotics will be used. (There are still antibiotics which will kill MRSA, but there is considerable concern that the MRSA may become more resistant, and that the ability to resist antibiotics will spread to other bacteria.)
- If a person in hospital is found to have MRSA additional precautions may be used, such as placing that person in a single room, extra handwashing etc.
Department of Health, South Australia, 'Staphylococcus aureus including methicillin resistant Staphylococcus aureus (MRSA)'
The information on this site should not be used as an alternative to professional care. If you have a particular problem, see a doctor, or ring the Parent Helpline on 1300 364 100 (local call cost from anywhere in South Australia).
This topic may use 'he' and 'she' in turn - please change to suit your child's sex.