Skin infections guide: types, symptoms, treatment, prevention

TL;DR:

Skin infections come from bacteria, fungi, viruses, or parasites.
Mild cases may heal at home. Deep or fast-spreading cases need care.
Red flags include fever, severe pain, or fast-spreading redness.
Treat the cause. Do not use leftover creams or partial antibiotics.
Good wound care and hygiene prevent many infections.

Skin infections: a clear, practical guide

Publisher: ClubRive. Author: ClubRive. Date: 2025-10-08.

Skin protects you from germs. When that barrier breaks, bugs can enter and cause infection. This guide explains the types, signs, treatment, and prevention. It also shows when to seek urgent care.

What counts as a skin infection

A skin infection happens when germs grow in the skin or nearby tissue. The main types are:

Bacterial. Often due to Staphylococcus or Streptococcus. Examples include impetigo, folliculitis, boils, and cellulitis.
Fungal. Caused by dermatophytes and yeasts. Examples include ringworm, athlete’s foot, jock itch, and intertrigo.
Viral. Caused by viruses like varicella zoster and herpes simplex. Examples include shingles and cold sores.
Parasitic. Caused by mites or insects. Example, scabies.

People with eczema, diabetes, poor circulation, or weak immunity get infections more easily. Cuts, bites, tattoos, piercings, and shaving nicks also raise risk.

Common symptoms to watch

Symptoms vary by cause and depth. Look for:

Redness, warmth, swelling, and pain.
Pus, crusts, or blisters.
Itch for many fungal or parasitic cases.
Fever or chills in deeper infections.
Fast-spreading redness or streaks toward the groin or armpit.
New numbness, purple skin, or severe pain out of proportion to the look.

If you feel unwell, or pain is severe, get care the same day.

When to seek urgent medical care

Go to urgent care or an emergency department if you have:

Fever above 38 C with a skin infection.
Rapid spread of redness within hours.
Severe pain, dusky or black skin, or large blisters.
Infection near the eyes, genitals, or a surgical wound.
Signs of sepsis, such as confusion, very fast heartbeat, or trouble breathing.
Weak immunity, cancer treatment, advanced diabetes, or leg swelling with redness.

These signs can point to cellulitis or a deep soft tissue infection. These need prompt antibiotics and close follow up.

How doctors diagnose skin infections

Your doctor starts with a history and exam. Key steps can include:

Swab or culture of pus or crusts to find bacteria.
KOH prep or a skin scraping to check for fungi.
Viral tests for shingles or cold sores in special cases.
Needle aspiration, ultrasound, or MRI if a deep pocket of pus is suspected.
Blood tests when you are very unwell or the infection is severe.

Self-diagnosis is often wrong. For example, ringworm can look like eczema. A test helps pick the right treatment.

Treatment basics by cause

Bacterial infections

Impetigo. Often appears as honey-colored crusts, near the mouth or nose. Usual care is a topical antibiotic for small areas. Oral antibiotics are used for larger areas or outbreaks.
Folliculitis and small boils. Warm compresses help. Many small boils drain on their own.
Abscesses. The key treatment is drainage by a clinician. Antibiotics are added if you have fever, many lesions, or risk factors.
Cellulitis. This is infection of deeper skin. It needs oral or IV antibiotics. Elevate the limb, rest, and use pain relief. Mark the edge of redness with a pen. If it spreads beyond the mark, seek care again.

Do not share antibiotics or stop early. Finish the full course even if the skin looks better.

Fungal infections

Ringworm, athlete’s foot, jock itch. Use a topical antifungal twice a day for 2 to 4 weeks. Keep skin dry. Wash socks and towels hot.
Yeast intertrigo. Dry the folds, use a topical antifungal, and consider barrier creams to cut friction.
Nail fungus and scalp ringworm. These often need oral antifungals for weeks to months. Your doctor may test before treatment.

Topical steroids can hide and worsen ringworm. Avoid steroid-only creams on scaly, ring-shaped rashes unless a clinician says so.

Viral infections

Cold sores. Antiviral creams or pills help if started early.
Shingles. Start oral antivirals within 72 hours of the rash to lower pain and reduce nerve damage. Keep blisters covered to reduce spread.

Parasitic infections

Scabies. Treat with permethrin cream from neck down, including under nails. Repeat in 7 days. Wash bedding and clothes on hot and dry on high heat. Treat close contacts on the same day to stop ping-pong spread.

Home care that helps most skin infections

Clean gently. Rinse with clean water or saline. Use mild soap.
Protect. Cover open areas with a breathable dressing.
Compress. Warm compresses help boils drain.
Elevate. Raise the limb to reduce swelling in cellulitis.
Pain control. Use paracetamol or ibuprofen unless told not to.
Do not pick, pop, or shave over infected skin.

If there is no improvement after 48 hours of proper care, check back with your doctor.

Quick guide: likely cause and first steps

This table gives clues. It is not a diagnosis. See a clinician for care.

Clue	More likely cause	First steps at home	Do not do
Itchy round ring with a clear edge on body	Fungal ringworm	Antifungal cream twice a day, keep dry	Do not use steroid-only cream
Red, warm, tender area that spreads, with fever	Bacterial cellulitis	Elevate, mark edge, seek care the same day	Do not delay antibiotics
Small yellow crusts near mouth or nose in child	Bacterial impetigo	Wash, cover, see GP for topical antibiotic	Do not send to school until 24 hours after starting antibiotics
Painful blister cluster on lip	Viral cold sore	Start antiviral at first tingle	Do not share cups or towels
Itchy rash in webs of fingers, worse at night	Scabies	Apply permethrin to all from neck down	Do not treat only one person in the home
Scaling between toes with itch and odor	Athlete’s foot	Dry well, antifungal spray or cream	Do not wear tight, sweaty shoes all day

Special groups who need extra care

Children. Impetigo spreads fast in schools. Keep nails short and cover lesions.
Athletes. Tinea and staph spread in shared gear and mats. Clean mats and do not share towels or razors.
People with diabetes or poor circulation. Check feet daily. Even small breaks can become serious.
Immunocompromised people. Call early for new infections. Some fungal infections are harder to diagnose and treat.
Travelers. Cuts, insect bites, and hot, humid climates raise risk. Pack plasters, antiseptic, and an antifungal cream.

Prevention that works

Wash hands often with soap and water, especially after sports or caring for wounds.
Keep skin dry, especially between toes and in skin folds.
Wear sandals in communal showers.
Do not share towels, razors, or nail clippers.
Clean and cover cuts. Change dressings daily or when wet.
Keep nails trimmed and clean.
For frequent cellulitis, ask your doctor about plans to prevent repeat attacks, such as foot care for athlete’s foot, leg elevation, and compression if advised.

Common mistakes

Using steroid cream on an undiagnosed scaly rash. This can hide and worsen ringworm.
Stopping antibiotics early. This raises the chance the infection returns.
Picking at boils. This can push pus deeper and spread germs.
Relying on home cures for severe infections. Deep infections need medical care.
Sharing creams or pills. Treatments are not one size fits all.

What to expect during recovery

Pain and redness may take 24 to 48 hours to settle after starting the right treatment. Swelling improves with elevation and compression if advised by your doctor. Fungal infections clear more slowly. Keep using antifungal cream for one week after the rash looks normal to prevent a rebound.

When to follow up

No improvement after 48 hours of the correct treatment.
Worsening pain, swelling, or spreading redness.
New fever, vomiting, or feeling very unwell.
Recurrent infections in the same spot. This may signal an underlying problem that needs care.

Why it matters

Skin infections are common and often preventable. Knowing early signs helps you act fast. Good wound care and smart hygiene lower your risk. Correct treatment shortens illness and prevents spread to others.

Simple 8-point checklist

Clean the area with soap and water.
Cover with a clean, dry dressing.
Mark the edge if red and spreading.
Elevate if a limb is involved.
Use correct medicine for the cause.
Avoid sharing towels and razors.
Recheck after 48 hours.
Seek urgent care if fever, severe pain, or fast spread.

Sources:

CDC, “Fungal Diseases,” https://www.cdc.gov/fungal/index.html, accessed 2025-10-08.
DermNet, “Skin infections,” https://dermnetnz.org/topics/skin-infections, accessed 2025-10-08.
Mayo Clinic, “Cellulitis – Symptoms & causes,” https://www.mayoclinic.org/diseases-conditions/cellulitis/symptoms-causes/syc-20370762, updated 2025-05-16, accessed 2025-10-08.

Skin infections guide