Staphylococcus bacteria cause staph infections. There are many types of staph infections, and, depending on the cause, doctors may use antibiotics, surgery, or other methods to treat them.

Most staph infections clear up quickly with treatment, but people with a weakened immune system are at higher risk and may take longer to recover.

A staph infection is an infection with the bacteria Staphylococcus, which people often refer to by the abbreviation “staph.” There are more than 30 types of Staphylococcus bacteria.

Staphylococcus aureus, which lives on the skin and in the nose of some people, is responsible for most infections.

These bacteria are usually harmless, but if they enter the body through a wound, scrape, or cut, they can cause infection and serious illness.

This article examines the causes, types, symptoms, and treatment of staph infections. It also discusses the risk factors and the recovery time for people with these infections.

Approximately 1 in 4 people carry staph bacteria on their skin.

Staph bacteria generally do not cause harm unless they enter the body through a wound. When this happens, the bacteria can cause an infection on the skin — producing an open sore — or in one of the systems of the body. These systemic infections can be severe and even fatal.

Staph infections are contagious. Sneezing, coughing, or touching an infected wound can spread the infection, but many cases occur when a person comes into contact with a contaminated object, such as a hand towel, remote control, or door handle. Direct person-to-person contact with someone who has the infection can also allow it to spread.

Staph bacteria can cause a variety of infections, including:

Antibiotics are effective treatments for most staph infections. There is also a type of staph called methicillin-resistant Staphylococcus aureus (MRSA) that is resistant to several antibiotics, although there are some that can treat it.

Staph infections can affect any area of the skin and, once they enter the body through an open wound, many internal systems. Without treatment, they can cause sepsis.

Although many people carry staph bacteria on their skin or in their nose, not all of them will develop a staph infection.

Infection only occurs when staph bacteria enter the skin or body through a cut, scrape, wound, or contaminated food.

Staph bacteria can spread to a person through skin-to-skin contact with someone with the infection. Therefore, the best way to avoid a staph infection is by practicing good hygiene. Proper hygiene practices are particularly important in areas where people congregate, such as public pools, schools, gyms, and residential facilities.

Some steps to follow include:

  • washing the hands thoroughly with soap and water
  • covering wounds with clean, dry bandages
  • disposing of bandages and dressings directly into the trash
  • avoiding picking at pimples or bumps on the skin
  • avoiding sharing personal items, such as towels, razors, and washcloths

The symptoms of a staph infection will vary depending on the type of infection and may include:

  • Skin infections: These can create bumps or sores that may swell or be painful. They may contain pus or other fluid, and a crust might form. Cellulitis can occur, in which the skin becomes discolored and feels warm.
  • Bone infections: These infections may bring pain, swelling, warmth, and discoloration to the area of infection. They can also cause fever and chills.
  • Endocarditis: Endocarditis is an infection of the heart’s lining. It creates flu-like symptoms, including fever, fatigue, chills, a fast heartbeat, and shortness of breath. It can also cause fluid to build up in the arms and legs.
  • Food poisoning: Food poisoning causes nausea, vomiting, diarrhea, fever, and possible dehydration.
  • Pneumonia: This infection of the lungs causes high fever, a cough, chills, possible chest pain, and shortness of breath.
  • TSS: TSS will cause a sudden drop in blood pressure, high fever, vomiting, diarrhea, and confusion. A sunburn-like rash may also develop.

When a doctor suspects a staph infection, they will ask the person questions about their symptoms and may take a blood test or culture of the affected skin. If they suspect staph, they will seek to begin treatment quickly to avoid further illness.

The cause of a staph infection is staph bacteria entering the body. They can enter through an open wound or when a person ingests food that has become contaminated with the bacteria.

Staph bacteria might enter a person’s body as a result of them:

  • picking or scratching at pimples, sores, or bumps on the skin
  • coming into contact with someone else who has a staph infection
  • being in a situation that gives them high exposure to the bacteria, such as surgery or a hospital stay
  • sharing personal items, such as towels, razors, or makeup, with someone with the infection
  • acquiring the bacteria from shared surfaces, such as gym equipment

People can take steps to protect themselves against infection from staph bacteria. These include:

  • washing the hands thoroughly with soap and hot water
  • covering cuts and scrapes with dry, clean bandages
  • drying clothes in a hot dryer, which kills bacteria
  • sanitizing shared surfaces regularly

Doctors prescribe antibiotics to treat staph infections. Depending on the type of infection, a doctor may prescribe:

  • oral antibiotics
  • creams or ointments
  • intravenous antibiotics

If a skin staph infection involves pus, a doctor may choose to drain it. Bone staph infections may require surgery.

A person with staph food poisoning should drink plenty of fluids to stay hydrated. Doctors do not prescribe antibiotics to treat staph food poisoning. Severe illness is rare, but some people may require intravenous fluids for dehydration from persistent vomiting or diarrhea.

MRSA infections are resistant to many types of antibiotics, but there are still other antibiotics that can treat them.

It is important to see a doctor if symptoms of a staph infection last longer than a week or worsen quickly. Anyone with a weakened immune system should also visit a doctor as soon as they suspect infection.

Some people have an increased risk of staph infections. These individuals include those who:

  • have had surgery
  • have a breathing or feeding tube or a catheter
  • are on dialysis
  • inject recreational drugs
  • have a chronic condition, such as diabetes, cancer, eczema, lung disease, or vascular disease
  • have a weakened immune system
  • play contact sports that involve skin-to-skin contact

People at higher risk should take care to wash their hands thoroughly and regularly and to sterilize shared surfaces whenever possible. They may also wish to avoid sharing personal items, such as towels, washcloths, and sports equipment.

The recovery time for a staph infection depends on the type and severity of the infection, as well as the strength of a person’s immune system.

Food poisoning staph will usually pass within 24–48 hours, but it may take 3 days or longer to feel well.

A staph infection at the surface of the skin may heal with just a few days of treatment. However, if a large sore or wound has developed, it may require several weeks of treatment or longer.

If a systemic staph infection develops in the heart, lungs, bloodstream, or another organ system, treatment can take weeks to months. In rare cases, these staph infections can lead to sepsis, a dangerous condition in which the immune system has an exaggerated response to infection.

It is normal for staph bacteria to live on the skin and in the nose of some people. Problems only arise when staph bacteria enter the body through a cut, wound, or contaminated food, when they can lead to infection.

Staph infections can take many forms. The most common are skin infections, which can either be minor and heal in a few days or be quite severe and take some time to heal.

Staph infections may also infect the bones, lining of the heart, lungs, blood, and other organs.

People who live, work, or play sports in proximity with others and those with certain health conditions have a higher risk of staph infections. Being in the hospital or having surgery also increases the risk of contracting a staph infection.

A person with symptoms of a staph infection should seek treatment to avoid complications. People who have a weakened immune system should speak with a doctor as soon as they suspect that they have an infection.