Staph infections are caused by staphylococcus bacteria, types of germs commonly found on the skin or in the nose of even healthy individuals. Most of the time, these bacteria cause no problems or result in relatively minor skin infections.
But staph infections can turn deadly if the bacteria invade deeper into your body, entering your bloodstream, joints, bones, lungs or heart. A growing number of otherwise healthy people are developing life-threatening staph infections.
Treatment usually involves antibiotics and drainage of the infected area. However, some staph infections no longer respond to common antibiotics.
Staph infections can range from minor skin problems to endocarditis, a life-threatening infection of the inner lining of your heart (endocardium). Because of this, signs and symptoms of staph infections vary widely, depending on the location and severity of the infection.
Skin infections caused by staph bacteria include:
Boils. The most common type of staph infection is the boil, a pocket of pus that develops in a hair follicle or oil gland. The skin over the infected area usually becomes red and swollen.
If a boil breaks open, it will probably drain pus. Boils occur most often under the arms or around the groin or buttocks.
Staph bacteria are one of the most common causes of food poisoning. Symptoms come on quickly, usually within hours of eating a contaminated food. Symptoms usually disappear quickly, too, often lasting just half a day.
A staph infection in food usually doesn't cause a fever. Signs and symptoms you can expect with this type of staph infection include:
Also known as a bloodstream infection, bacteremia occurs when staph bacteria enter a person's bloodstream. A fever and low blood pressure are signs of bacteremia. The bacteria can travel to locations deep within your body, to produce infections affecting:
This life-threatening condition results from toxins produced by some strains of staph bacteria and has been linked to certain types of tampons, skin wounds and surgery. It usually develops suddenly with:
Septic arthritis is often caused by a staph infection. The bacteria often target the knees, shoulders, hips, and fingers or toes. Signs and symptoms may include:
Go to the doctor if you or your child has:
You may also want to consult your doctor if:
Many people carry staph bacteria and never develop staph infections. However, if you develop a staph infection, there's a good chance that it's from bacteria you've been carrying around for some time.
These bacteria can also be transmitted from person to person. Because staph bacteria are so hardy, they can live on objects such as pillowcases or towels long enough to transfer to the next person who touches them.
Staph bacteria are able to survive:
A variety of factors — including the status of your immune system to the types of sports you play — can increase your risk of developing staph infections.
Certain disorders or the medications used to treat them can make you more susceptible to staph infections. People who may be more likely to get a staph infection include those with:
Despite vigorous attempts to eradicate them, staph bacteria remain present in hospitals, where they attack the most vulnerable, including people with:
Staph bacteria can travel along the medical tubing that connects the outside world with your internal organs. Examples include:
Staph bacteria can spread easily through cuts, abrasions and skin-to-skin contact. Staph infections may also spread in the locker room through shared razors, towels, uniforms or equipment.
Food handlers who don't properly wash their hands can transfer staph from their skin to the food they're preparing. Foods that are contaminated with staph look and taste normal.
If staph bacteria invade your bloodstream, you may develop a type of infection that affects your entire body. Called sepsis, this infection can lead to septic shock — a life-threatening episode with extremely low blood pressure.
These commonsense precautions can help lower your risk of developing staph infections:
Wash your hands. Careful hand-washing is your best defense against germs. Wash your hands with soap and water briskly for at least 20 seconds. Then dry them with a disposable towel and use another towel to turn off the faucet. If your hands aren't visibly dirty, you can use an alcohol-based hand sanitizer.
Wash your hands with soap and water regularly, such as before, during and after making food; after handling raw meat or poultry; before eating; after using the bathroom; and after touching an animal or animal waste.
Wash clothing and bedding in hot water. Staph bacteria can survive on clothing and bedding that isn't properly washed. To get bacteria off clothing and sheets, wash them in hot water whenever possible.
Also, use bleach on any bleach-safe materials. Drying in the dryer is better than air-drying, but staph bacteria may survive the clothes dryer.
To diagnose a staph infection, your doctor will:
Treatment of a staph infection may include:
Antibiotics. Your doctor may perform tests to identify the staph bacteria behind your infection, and to help choose the antibiotic that will work best. Antibiotics commonly prescribed to treat staph infections include certain cephalosporins such as cefazolin; nafcillin or oxacillin; vancomycin; daptomycin (Cubicin); telavancin (Vibativ); or linezolid (Zyvox).
Vancomycin increasingly is required to treat serious staph infections because so many strains of staph bacteria have become resistant to other traditional medicines. But vancomycin and some other antibiotics have to be given intravenously.
If you're given an oral antibiotic, be sure to take it as directed, and to finish all of the medication prescribed by your doctor. Ask your doctor what signs and symptoms you should watch for that might indicate your infection is worsening.
Staph bacteria are very adaptable, and many varieties have become resistant to one or more antibiotics. For example, only about 5% of today's staph infections can be cured with penicillin.
The emergence of antibiotic-resistant strains of staph bacteria — often described as methicillin-resistant Staphylococcus aureus (MRSA) strains — has led to the use of IV antibiotics, such as vancomycin or daptomycin, with the potential for more side effects.
While you may initially consult your family doctor, he or she may refer you to a specialist, depending on which of your organ systems is affected by the infection. For example, you may be referred to a doctor trained in treating skin conditions (dermatologist), heart disorders (cardiologist) or infectious diseases.
You may want to write a list that includes:
For a staph infection, some basic questions to ask your doctor include:
Your doctor will likely ask you a number of questions, such as:
If you suspect you have a staph infection on your skin, keep the area clean and covered until you see your doctor so that you don't spread the bacteria. And, until you know whether or not you have staph, don't prepare food.
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