Skin Infection

Medically Reviewed by Stephanie S. Gardner, MD on May 01, 2023
4 min read

A skin infection is a condition in which germs (bacteria, viruses, or fungi) infect your skin and sometimes the deep tissues underneath it. In some cases, it’s caused by a parasite invading your skin. You can get a skin infection any time your skin is broken, whether from a cut, tattoo, piercing, puncture, sting, or bite.

Some infections happen at the skin’s surface, but they can start deeper in the wound. You can treat minor skin infections at home, but you might have to go to the doctor or emergency room for a more serious one.

If you think your skin may be infected, watch for these signs:

  • Pus or fluid leaking out of the cut
  • Red skin around the injury
  • A red streak that radiates from the injury
  • A pimple or yellowish crust on top
  • Sores that look like blisters
  • Pain that gets worse after a few days
  • Swelling that gets worse after a few days
  • A fever
  • The wound hasn’t healed after 10 days

It can be hard to tell the difference between an infection and eczema, especially in children. People with eczema often get skin infections because the breaks in their skin let germs in. If an eczema treatment doesn’t work, or if the rash gets worse, it could be an infection.

When to see a doctor

Call a doctor or go to the hospital right away if you think you might have a skin infection and:

  • You have a fever of 100.4 degrees or higher.
  • You’re in a lot of pain.
  • The redness or swelling spreads.

Pink or red skin and swelling around a wound are normal, especially if you have stitches. Some amount of pain is normal, but it should start to go away after the second day.

If you see pus, fluid, or crust, call your doctor within 24 hours. Call if the pain gets worse after 48 hours.

Bacteria, a fungus, or a virus can cause skin infections. Common types include:

Boils. This is the most common type of skin infection. It’s usually caused by staph bacteria. It’s a pocket of pus that forms over a hair follicle or oil gland. Your skin gets red and swollen. If it breaks open, pus likely will drain out.

Impetigo. This contagious rash usually shows up as blisters with a honey-colored crust. Staph or strep bacteria are usually to blame.

Cellulitis. This bacterial infection grows in the deepest layers of your skin. It causes redness, swelling, and sores on the surface and can be painful.

Ringworm. It has nothing to do with worms. Its name comes from the circular shape of the rash it causes. The spots also have a border that’s slightly raised and darker in color. This fungal infection can appear anywhere on your body. Athlete’s foot and jock itch are types of ringworm.

MRSA. This bacterial infection can be dangerous because it resists some antibiotics. That means antibiotics used to treat staph infections don’t work like they should. The rash usually shows up as painful red bumps that look like pimples or spider bites. It may be warm to the touch, and you might have a fever. This skin infection often shows up in schools, military barracks, nursing homes, and other places where people live in close quarters.

Eczema  It’s a group of conditions that includes atopic dermatitis, contact dermatitis, seborrheic dermatitis, and others that inflame and dry out the skin. You might notice a red rash, serious itchiness, or thickened or scaly skin. Eczema can weaken the skin’s protective barrier and allow bacteria and other germs that live on the skin to go deeper, which can lead to more infection from bacteria like staph and viruses like herpes.

To diagnose a skin infection, your doctor will start off by looking at the affected area and any bumps or sores. They may also ask you about your symptoms. Since skin infections can result from many different types of germs, you may need lab tests to get a proper diagnosis. The doctor will collect samples of pus, fluids, or skin scrapings and send them to a lab for more testing. This will help them give you the right treatment.

If you have an infection, your doctor may prescribe medicine. What they give you depends on the type of infection:

  • Antibiotics fight a bacterial infection.
  • Antivirals treat viral infections.
  • Antifungal creams, ointments, powders, or pills treat fungal infections.

Any break in the skin can lead to a tetanus infection if your tetanus shot isn’t up to date. Check with your doctor to see if you need a booster shot. You should get a tetanus booster every 10 years.

Proper handwashing is important. Use soap and warm water to scrub your hands for 20 seconds, then rinse and dry with a clean towel or paper towel. Use hand sanitizer if soap and water aren't nearby.

If you’re an athlete or go to the gym often, use a clean towel as a barrier between your skin and shared surfaces like exercise machines or locker room benches. If the gym has sanitizer or cleaner and paper towels to clean gym equipment before and after you’re on it, use them. Shower and wash your clothes and towel after every workout.

If you have a minor cut or break in your skin, keep it clean. Wash it with warm water and soap. You also can use an antibiotic ointment like bacitracin or even plain vaseline, and cover it with a clean bandage.

If you have a major skin wound, especially one with stitches, check with your doctor for proper care instructions.