SymptomSkin, hair & nails
Skin Infections on Various Body Parts
Skin infections happen when bacteria, fungi or viruses get into or grow on the skin, and each part of the body has its usual suspects. Red, warm, spreading skin on the legs is often cellulitis; itchy, ring-shaped or peeling rashes in the groin, feet and skin folds are usually fungal; and honey-crusted sores on a child's face suggest impetigo. Spreading redness with fever, severe pain or red streaks needs same-day care. Repeated infections in several places can point to diabetes, MRSA carriage or a weak immune system.
Also called: Skin infection, infected skin, recurrent skin infections, bacterial or fungal skin infections
At a glance
- What it is
- Infection of the skin or the tissue just beneath it.
- Bacterial examples
- Cellulitis, impetigo, folliculitis, boils, infected wounds.
- Fungal examples
- Athlete's foot, jock itch, ringworm, yeast in skin folds, nail fungus.
- Viral examples
- Cold sores, shingles, warts, molluscum.
- Red flags
- Fast-spreading redness, red streaks, fever, severe pain or dark, blistered skin.
- Treatment
- Antibiotics, antifungals or antivirals depending on cause, plus drainage of abscesses.
When to get help
Call 911 or go to the ER
- Rapidly spreading redness with severe pain out of proportion to how the skin looks, dusky or blistered skin, or crackling under the skin (possible necrotizing fasciitis)
- Skin infection with confusion, low blood pressure, very fast heartbeat or feeling extremely unwell (possible sepsis)
- Swelling and redness around the eye with pain on moving the eye, double vision or bulging (possible orbital cellulitis)
See a doctor within a day or two
- Red, warm, swollen, tender skin that is spreading, especially with fever of 38 °C (100.4 °F) or higher
- Red streaks running up a limb from a wound (lymphangitis)
- A painful lump full of pus larger than about 2 cm (3/4 in), or a boil on the face
- Any infected-looking wound or foot sore in someone with diabetes
- A painful blistering rash in a band on one side of the body, especially near the eye (possible shingles)
Book a routine appointment
- Itchy, scaly, ring-shaped or peeling rash that does not clear with 2 weeks of over-the-counter antifungal
- Repeated boils or skin infections, or several family members affected
- Thick, discolored, crumbling nails
Usually safe to manage at home
- Mild athlete's foot or jock itch without broken skin or spreading redness
- A single small pimple-like bump at a hair follicle
- A small cut with mild redness at the edges only, which is improving
Skin infections by body part
| Body area | Common infections | Typical clues |
|---|---|---|
| Face | Impetigo, cold sores, folliculitis, cellulitis, erysipelas, shingles | Honey-colored crusts around nose and mouth; lip blisters; sharply raised red patch on the cheek |
| Scalp | Folliculitis, scalp ringworm, infected cysts | Pustules at hair roots; patchy hair loss with scale in children |
| Eyelids and around eye | Stye, preseptal or orbital cellulitis | Red, swollen lid; pain on moving the eye is a red flag |
| Armpits and groin | Boils, hidradenitis flares, jock itch, candida | Painful lumps; itchy red rash with raised edge; red rash with satellite spots in folds |
| Under breasts, belly folds | Intertrigo with candida or bacteria | Raw, moist red skin, sometimes smelly |
| Hands and fingers | Paronychia, infected cuts, herpetic whitlow | Red, swollen nail fold with pus; painful blisters on a fingertip |
| Legs | Cellulitis, erysipelas, infected insect bites, folliculitis after shaving | Warm, tender, spreading redness, usually on one leg |
| Feet | Athlete's foot, nail fungus, infected ulcers, cellulitis | Peeling between toes; thickened nails; sores in diabetes |
| Buttocks and thighs | Boils, MRSA abscesses, folliculitis | Painful pus-filled lumps, often mistaken for spider bites |
| Trunk | Ringworm, tinea versicolor, shingles, folliculitis | Ring-shaped patches; light or dark spots; band of blisters |
Bacterial skin infections
Bacterial skin infections are mostly caused by Staphylococcus aureus (including MRSA) and Streptococcus bacteria, entering through cuts, insect bites, cracks from athlete's foot, eczema or shaving.
- Cellulitis: a deeper infection with warm, red, swollen, tender skin that spreads, usually on one lower leg. Often with fever. Both legs red and itchy is more often venous eczema than cellulitis.
- Impetigo: a superficial, contagious infection common in children, with sores that burst and form golden crusts, mostly around the nose and mouth.
- Folliculitis: small red bumps or pustules at hair follicles, after shaving, hot tubs or tight clothing.
- Boils and abscesses: painful, swollen lumps filled with pus. Larger ones need drainage.
- Erysipelas: a superficial cellulitis with a sharply defined, raised, bright red border, often on the face or legs.
Fungal skin infections
Fungal skin infections thrive in warm, moist areas:
- Athlete's foot (tinea pedis): itchy, peeling, cracked skin between the toes.
- Jock itch (tinea cruris): itchy, red rash in the groin with a raised edge, usually sparing the scrotum.
- Ringworm (tinea corporis): ring-shaped scaly patches with clearer centers.
- Candida (yeast): bright red, moist rash in skin folds with small "satellite" spots, common in diabetes, obesity and babies (diaper rash).
- Tinea versicolor: pale, pink or brown patches on the chest and back.
- Nail fungus: thick, yellow, crumbly nails.
Viral skin infections
- Cold sores (herpes simplex) on the lips.
- Shingles: a painful band of blisters on one side of the body.
- Warts and molluscum contagiosum: small growths spread by contact.
Why skin infections keep coming back
Recurrent infections in different places suggest a predisposing factor:
- MRSA or staph carriage in the nose, armpits or groin, often shared within households or sports teams
- diabetes or high blood sugar
- eczema or other conditions that break the skin barrier
- leg swelling (lymphedema), which predisposes to recurrent cellulitis
- obesity, sweating and skin folds
- a weakened immune system from medicines, cancer treatment or HIV
- athlete's foot, which lets bacteria into the leg and causes repeated cellulitis
How skin infections are diagnosed
Most are diagnosed by examination. A doctor may take a swab of pus, skin scrapings for fungus, or blood tests (blood sugar, blood count and inflammatory markers) in more severe or recurrent infections. Imaging is used if a deep abscess, bone infection or necrotizing infection is suspected.
Treatment
- Bacterial: antibiotic ointment for small areas of impetigo; oral antibiotics for cellulitis and widespread infection; drainage for abscesses; IV antibiotics in hospital for severe infections.
- Fungal: antifungal creams such as terbinafine or clotrimazole for 2 to 4 weeks; tablets for scalp, nail or widespread infections.
- Viral: antiviral medicines for cold sores and shingles when started early.
- Recurrent staph infections: decolonization regimens such as antiseptic body washes and a nasal antibiotic ointment, and washing towels and bedding.
Mark the edge of spreading redness with a pen. If it moves beyond the line despite treatment, see a doctor again.
Preventing skin infections
- Clean cuts and scrapes promptly and cover them.
- Keep skin folds and feet dry; change socks daily.
- Treat athlete's foot and eczema.
- Do not share towels, razors or sports equipment.
- Keep blood sugar well controlled if you have diabetes.
- Elevate swollen legs and wear compression if advised.
Frequently asked questions
What are the most common skin infections?
The most common are bacterial infections such as cellulitis, impetigo, folliculitis and boils, fungal infections such as athlete's foot, jock itch, ringworm and yeast in skin folds, and viral infections such as cold sores, shingles and warts. The body area affected often points to the cause.
Why do I keep getting skin infections?
Recurring skin infections are often linked to staph or MRSA carriage, diabetes, eczema, obesity, swollen legs, athlete's foot or a weakened immune system. A doctor can test for diabetes, take swabs, and suggest decolonization or treatment of the underlying problem.
How do I know if a skin infection is serious?
Warning signs include redness that spreads quickly, red streaks, fever, severe pain, skin turning dark or blistered, or feeling very unwell. Infections near the eye or on the face, and any infection in someone with diabetes or a weak immune system, also need prompt care.
Is a skin infection bacterial or fungal?
Bacterial infections are usually painful, warm and red, sometimes with pus. Fungal infections are usually itchy, scaly and slowly spreading, often with a ring shape or in moist folds. Some can look alike, so a doctor may take scrapings or swabs.
Can skin infections spread to other parts of the body?
Yes. Fungal infections can spread from feet to groin or hands by touch or towels. Impetigo spreads by scratching. Bacterial infections can extend into deeper tissue or the bloodstream, which is why spreading redness with fever needs urgent treatment.
Sources
This guide was written from current patient and clinical guidance, including:
- American Academy of Dermatology: Cellulitis; Impetigo; Ringworm
- Infectious Diseases Society of America: Practice guidelines for skin and soft tissue infections
- CDC: Methicillin-resistant Staphylococcus aureus (MRSA)
- NHS: Cellulitis; Fungal nail infection
- MedlinePlus: Skin infections