Waitematā DHB Dermatology Service
Bacterial Skin Infections
Our skin is our body’s first defence mechanism and even though many types of bacteria live on its surface, we still need a healthy, intact skin surface to maintain its defence. Any break in this defence, whether it is from a cut or a pimple, is a possible risk for a bacterial infection.
Some diseases such as diabetes and HIV increase the risk of major infection when this barrier is broken, as these patients already have a faulty immune system.
This is a bacterial infection of the outer layers of the skin. It is infectious and is spread to others by direct contact, but can also spread to other areas on the body. It shows up as a crusty, weepy area and most often begins on the face or exposed areas of the arms and legs. The bacteria that causes it is commonly found around children and schools. Thus, impetigo is more common among children than adults and often occurs in spring and autumn.
Impetigo is easily treated with oral or topical antibiotics.
In some cases a child may require time off from school to prevent spread to others.
This is a bacterial infection of the skin and underlying tissues that can happen in normal skin but often occurs in an area of skin damaged by a wound, insect bite, eczema, chicken pox etc. It usually involves the skin of the face, arms and legs. Bacteria spread and cause the following symptoms:
- swelling, pain and inflammation of tissue
- warmth and redness of skin
- aches and general unwellness
- red streaks from original cellulitis site.
In someone with diabetes or someone who is taking medications to suppress the immune system, cellulitis can start in areas of intact skin.
The bacteria that cause cellulitis are usually Streptococcus or Staphylococcus.
Cellulitis responds rapidly to antibiotic treatment, either orally or through injections.
This is a tender, red, inflamed raised lump that has a pus-filled centre. A boil develops when a hair follicle becomes infected with bacteria. The usual bacteria that causes a boil is Staphylococcus. Common areas of infection are the neck and face, breast and buttocks.
Boils are more prevalent in people who have a low immunity.
This is the term for a cluster of boils.
This is inflammation of the hair follicle, caused by the Staphylococcus bacteria.
The inflammation produces pus-filled pimples around the follicle. It can occur on any area of the body but is more common in areas that are shaved or plucked.
Often boils, carbuncles and folliculitis clear without any specific treatment. They may burst and release the pus.
Keeping the skin clean with antibacterial wash can prevent infections and prevent the spread. Do not squeeze as this can spread and worsen the infection.
Application of warm heat can help to relieve symptoms. Antibiotics can be prescribed in some cases.