What is a bacterial skin rash?

A bacterial skin rash occurs when your skin becomes infected with certain types of bacteria, causing red bumps or a rash. There are several types of infection. They are often mild and can go away on their own, but sometimes antibiotics are used to treat them.

Different types of bacterial skin infections include:

• cellulitis
• impetigo
• erysipelas
• bacterial folliculitis
• erythrasma
• carbuncles
• furuncles

They happen when bacteria enter your skin when it is damaged or broken often because of a skin condition, or  a cut or  bite. Bacterial skin infections are common and usually straightforward to treat. But if they go untreated, some can cause serious and even life-threatening complications. 

Common bacterial skin rashes

There are several common bacterial skin infections and rashes.

Cellulitis

Cellulitis affects the deepest layers of the skin, your subcutaneous tissue and dermis. It usually causes swollen red areas on your skin which can feel sensitive, inflamed, and hot when you touch them.

It normally occurs where your skin is broken, often on your lower legs, but can happen in other areas including your face and arms. Cellulitis is caused by bacteria (typically staphylococcus or streptococcus) entering through the broken skin. It can be deadly if it spreads to your lymph nodes and bloodstream, so it is very important you get it treated immediately.

Cellulitis can be treated with a prescription oral antibiotic. You must finish the course, even if you feel better and your symptoms are disappearing. If your symptoms do not respond to treatment, become worse, or you have a high fever, you may need antibiotics injected through your veins in hospital.

Erysipelas

Erysipelas is an infection of the top two layers of your skin. It causes your skin to become very red and swollen, with a clear distinction between normal and infected skin. It can look a bit like cellulitis, but cellulitis occurs deeper in your skin.

Erysipelas is sometimes referred to as “St. Anthony’s fire” because of the burning sensation it causes. The infection is caused by a bacteria called streptococcus entering through a break in your skin, or through your nasal passages.

It is treated using antibiotics, often containing penicillin. If you are allergic to penicillin, tell your doctor so they can prescribe an alternative. Antibiotics are usually taken for 7 to 14 days. If they do not work, you may need antibiotics injected into your veins. Starting treatment as soon as possible will help to minimise the risk of further complications.

Bacterial Folliculitis

Bacterial folliculitis is a common infection of the hair follicles on your skin. It can occur anywhere you have hair follicles, and normally causes small red bumps or white-headed spots with pus inside. 

It is normally caused by ingrown hair, blockages caused by products put onto your skin, or a fungus. Plucking hairs out of your skin, and shaving can both increase your risk of bacterial folliculitis.

Bacterial folliculitis normally heals on its own, but it sometimes requires antibiotics if the infection is particularly bad or persistent. If a bad case of bacterial folliculitis is left untreated it can cause permanent hair loss.

Hot Tub Folliculitis

Hot tub folliculitis is an infection which causes an itchy red rash and pus-filled bumps on your skin. It happens when your skin is infected by bacteria that are often found in hot tubs, whirlpools, and jacuzzis. It often occurs on your chest or groin anywhere from a few hours to a few days after you are exposed to the bacteria.

A bacteria which can survive in chlorinated water called pseudomonas aeruginosa causes hot tub folliculitis, making it difficult to prevent. Children are more vulnerable than adults to it because their skin is not as thick. People with acne or dermatitis are also at greater risk because their conditions can allow the bacteria into their skin.

There is no particular treatment for hot tub folliculitis and it normally clears up within 14 days. If your condition worsens or persists, contact your GP.

Furuncles (Boils)

Furuncles are a painful infection around a hair follicle, sometimes called a boil. They start small and become larger as they fill with pus. They often occur on your face, neck, buttocks, armpits, or thighs. 

Furuncles are different to bacterial folliculitis because they infect not only the hair follicle but also the area around it. Compressing a warm towel can help drain a furuncle. If it gets worse or persists, contact your GP, who may need to puncture it with a sterile instrument to drain the pus. If you do not get it treated, it can turn into a more serious infection called an abscess.

Carbuncles

A carbuncle is when furuncles (boils) cluster together on your skin. A carbuncle can be up to 4 inches (about 10cm) across, and have multiple openings where pus comes out. It can also cause you to feel weak and exhausted and have a fever.

Carbuncles often occur on your thighs, back, or the back of your neck. It is often deeper in your skin, and more serious than furuncles. It is typically caused by staph bacteria and is contagious. If you have a carbuncle, you should seek medical attention. A doctor will usually incise and drain it, and in some cases you may require antibiotics.

Impetigo

Impetigo is a common bacterial skin infection. It is highly contagious, but it’s not normally serious and symptoms usually go away after 7 to 10 days with treatment. It typically affects children aged 2 to 5, but adults can sometimes get it too.

Impetigo occurs when skin – particularly broken and irritated skin – comes into contact with staphylococcus or streptococcus bacteria, which can spread through skin-to-skin contact, clothing, towels and other items. It causes blisters and sores, usually around the nose and mouth, which burst and form a golden-coloured crust. It can be itchy and painful. Impetigo is very common in young children. It is usually treated with topical antibiotics.

Erythrasma

Erythrasma is a skin infection caused by a bacteria called Corynebacterium minutissimum. It causes pink patches on your skin that are scaly and wrinkled, which later become red, and then brown. It normally occurs in areas where your skin comes into contact with itself, such as your armpits, between your toes, or your groin. It can often look similar to athlete’s foot. 

Symptoms are usually mild, with some itchiness and burning, especially if the infection is in your groin. It is especially common in humid and hot environments. Erythrasma can be treated in several ways, including oral antibiotics, antibiotic soap, fusidic acid, antibacterial solutions and creams, and red light therapy. Treatments can take two to four weeks to work and are sometimes used in combination.

MRSA skin infections

Methicillin-resistant staphylococcus aureus (MRSA) is a bacterial infection which can be serious, as it resists standard antibiotics. It can cause mild sores on your skin that look like blisters. MRSA can become serious if it spreads into other parts of your body, such as your lungs, through the bloodstream. Symptoms may also include redness, swelling, pus, a fever, or pain. A lab test can be used to diagnose MRSA, and it can be treated using special antibiotics which work against it. You may have to isolate away from others to stop the infection from spreading.

How are bacterial skin rashes diagnosed?

If you think you might have a bacterial skin infection, you should see a doctor, or use Superdrug Online Doctor’s skin condition diagnosis service to get the correct diagnosis and to have a treatment recommended. In some cases, your GP may refer you to a dermatologist for specialist treatments.

It is especially important to contact a doctor if you have a skin rash and have:

• a sore throat
• been bitten recently by an animal or insect
• pain in your joints
• red streaking near your rash
• tender skin near to the rash
• a lot of pus

If you have any of the following symptoms, go to the hospital immediately:

• rapid changes in the colour of your skin
• difficulty with breathing
• feeling like your throat is closing up
• increased or severe pain
• high fever, confusion, dizziness
• swelling on your face, hands, or feet
• repeated diarrhoea and vomiting

How to prevent bacterial skin rashes

Bacterial skin rashes cannot always be prevented. However, practising good hygiene can help. This includes:

• regularly washing your hands with soap for 20 seconds
• covering up damaged skin, including cuts and bites, and keeping it clean and dry
• having a bath or shower daily
• using disposable tissues
• avoiding sharing towels, linens, toothbrushes, and razors with others

Sources

Staph Infection NHS [accessed 24th August 2022]

Skin Infection Healthline [accessed 24th August 2022]

Preventing Skin Infections Department of Health, New York State [accessed 24th August 2022]

Impetigo NHS [accessed 9th August 2022]

Erythrasma Healthline [accessed 25th August 2022]

MRSA NHS [accessed 25th August 2022]