- Staph (Staphylococcus aureus) is a common bacterium that lives on skin and in the nose. About 30% of people carry it in their nose, usually with no harm.¹
- Anyone can get a staph infection. The risk is higher after surgery or a hospital stay, with some long-term health conditions, and in close-contact settings.¹
- Most staph infections start in the skin and can look like a pimple, boil or other skin problem.¹
- Some staph infections are serious. If you have a fever, spreading redness or feel very unwell, get medical care right away.
What is staph?
Staphylococcus aureus, or staph, is one of the most common bacteria on the human body. It lives on skin and inside the nose, and for most people, most of the time, it causes no problems at all.¹ Carrying staph without symptoms is called being “colonized”, and it is far more common than infection.
Problems start when staph gets past the skin, through a cut, a scrape, a surgical wound, an insect bite or even a shaving nick. There it can cause an infection. MRSA is a type of staph that doesn’t respond to some common antibiotics, which can make it harder to treat.¹
Who gets staph?
Anyone can. Staph doesn’t pick an age, a job or a sport. Some groups do face higher risk, according to the CDC and other public-health sources:¹
- Older adults and people in hospitals or nursing homes, especially after surgery or with medical devices like catheters or IV lines.
- People with long-term conditions such as diabetes, or a weakened immune system.
- Healthcare workers and caregivers, who are in close contact with people who may carry staph.
- Families sharing a home, where towels, razors, bedding and bathrooms are shared.
- Athletes and gym-goers, where skin contact, scrapes and shared equipment add up.
- Children in daycare, school and youth sports.
What a staph infection looks like
Most staph infections show up on the skin. They can look like a pimple, a boil or another skin problem.¹ Common signs include:
- A red, swollen bump that is warm and painful to touch
- A boil or pus-filled spot, sometimes with a yellow or white center
- Crusty or honey-colored sores (often called impetigo), common in children
- A patch of red, tender skin that is spreading
Staph can also cause serious infections inside the body, in the blood, lungs, heart valves or bones.¹ These need urgent medical care.
How staph spreads
Staph moves mainly through skin-to-skin contact and through things that touch skin. The CDC advises against sharing items such as towels, razors and needles.¹ It can also sit on surfaces people touch every day: door handles, gym equipment, phones and bedding.
That is why staph often passes between people who live, work or train together, and why the same household can see repeat infections.
When to see a doctor
Call a doctor or get care if you notice any of these:
- A bump or patch that is red, swollen, warm, painful or full of pus
- Redness that is spreading, or red streaks moving away from a wound
- Fever or chills with a skin infection
- A skin infection that isn’t improving, or keeps coming back
- Any infection in someone who is older, has diabetes, or has a weakened immune system
Don’t squeeze or drain a boil yourself, and don’t try to treat a suspected staph or MRSA infection with home remedies. A doctor can test it and choose the right treatment.
How to lower your risk
- Wash your hands often with soap and water, or use an alcohol-based sanitizer.
- Keep cuts and scrapes clean and covered until they heal.
- Don’t share towels, razors, washcloths or other personal items.¹
- Wash towels and bedding regularly, and dry them completely.
- Clean shared surfaces at home, especially if someone has a skin infection.
- If you’re prescribed antibiotics, take them exactly as directed.
- Centers for Disease Control and Prevention. Staphylococcus aureus Basics.