Background
Staphylococcus aureus bacteria — usually simply called staph — is commonly found on your skin or in your nose or throat. Most of the time, the bacteria cause no problems or minor skin infections. But staph infections can turn deadly if the bacteria burrow deeper into your body, getting into your bloodstream, urinary tract, lungs and heart.

In recent years, a growing number of otherwise healthy people, many of whom have never been in a hospital, also are developing life-threatening staph infections. A greater problem is that many staph infections no longer respond to common antibiotics. Though most staph infections can still be successfully treated, it may only be a matter of time before the bacteria become resistant to all currently available medications.

Staph infections can range from minor skin problems to food poisoning, fatal pneumonia and surgical wound infections. As a result, signs and symptoms of staph infections vary widely, depending on the location and severity of the infection and on whether your illness results from direct infection with staph bacteria or from toxins the bacteria produce.

• Skin infections. Staph bacteria cause most skin infections, including boils; cellulitis and impetigo, a rash common in young children and infants. Though each condition has specific features, most begin with skin redness, swelling, warmth, tenderness and sometimes fever. Some staph infections are localized; others can cover your entire body.
• Food poisoning. Signs and symptoms of staph-related food poisoning usually come on quickly — as soon as one to six hours after eating contaminated food. They include abdominal cramps, nausea, vomiting and diarrhea. The illness often leaves just as suddenly as it came, and most people recover in a day or two, though the effects can be more serious and longer lasting in children and older adults.
• Methicillin-resistant staphylococcus aureus (MRSA). In the 1970s, a particularly dangerous and drugresistant form of staph infection called MRSA appeared in hospitals. MRSA infections often begin as a superficial skin problem that resembles a pimple or spider bite, but which can quickly turn into a deep, painful abscess that requires surgical draining.
• If the bacteria spread deeper into your body, they can cause fatal infections in your bloodstream, bones, heart lining or lungs. The symptoms vary, depending on which part of your body is affected, but most infections are accompanied by fever, chills and sweats.

How do you get a staph infection?
Staph bacteria can cause illness in two ways: through direct infection, which happens in most staph-related skin infections, and through toxins that the bacteria produce. These toxins are to blame for food poisoning and some serious MRSA infections. Here's how they break through your body's defenses:

• Skin infections. Most skin infections develop when staph bacteria enter your body through a cut or other break in your skin. Having eczema, psoriasis, irritation after shaving, or any condition that makes your skin more sensitive increases your risk of infection.
• Food poisoning. Staph bacteria thrive in foods that are improperly handled or stored, especially potato, egg, tuna and chicken salads, cream-filled pastries and pies, mayonnaise-based salad dressings, cream sauces, and custards. Staph grows best at room temperature, so refrigerating these foods is key.
• MRSA. This form of staph first emerged in hospitals, and it remains a growing threat in health care facilities worldwide. In 1974, MRSA accounted for only 2 percent of all staph infections. Thirty years later, 60 percent of staph infections were drug resistant. Part of the increase is due to staph's own survival tactics; but most of the blame lies with the overuse of antibiotics in humans and animals. Because antibiotics are so widespread in the environment, including in meat and municipal water supplies, germs have many opportunities to become resistant to them. In hospitals and nursing homes, MRSA can spread on the hands of health care workers and on many surfaces, including bedrails, catheters, cart handles — even remote controls.

Risk factors
Anyone can pick up a staph infection, but MRSA targets specific populations.
Risk factors for MRSA include:

• A current or recent hospitalization. MRSA remains widespread in hospitals, where it attacks the most vulnerable
• Residing in a long term care facility. MRSA is more common in these facilities than it is in hospitals. Most people admitted to a care facility are likely to carry MRSA and have the ability to spread it
• Invasive devices. People who are on dialysis, are catheterized or have feeding tubes are at especially high risk because the bacteria can easily enter the body through these devices.

These are the main risk factors for MRSA acquired outside the hospital setting.

• Young age. MRSA can be particularly deadly in children. The bacteria usually enter through a cut or scrape but can quickly cause a massive infection. Children and young adults are also much more likely to develop pneumonia than older people. Children may be susceptible because their immune systems aren't fully developed, or they don't yet have antibodies to common germs.
• Participating in contact sports. MRSA has crept into both amateur and professional sports teams. The bacteria spread easily through cuts, scrapes and skin-to-skin contact.
• Sharing towels or athletic equipment. MRSA has been known to spread among athletes who share razors, towels, uniforms or equipment.
• Having a weakened immune system. People with weakened immune systems, including those living with HIV/AIDS, are more likely to have severe MRSA infections.
• Living in crowded or unsanitary conditions. Outbreaks of MRSA have occurred in military training camps and in some American and European prisons, killing inmates and infecting guards and other staff.

When should I call the Doctor?
Keep an eye on minor skin problems — pimples, insect bites, cuts and scrapes — especially in children. If wounds become infected, see your doctor. Ask to have any skin infection tested for MRSA before starting antibiotic therapy. Drugs that treat ordinary staph aren't effective against MRSA, and their use could lead to serious illness and more-resistant bacteria.

Is there a test to see if I have MRSA or a Staph infection?
Most often, doctors diagnose staph infections by checking a tissue sample or nasal secretions for signs of the bacteria. These tests are done in a lab. However, in the time it takes the bacteria to grow — about 48 hours — people who have MRSA infections can become worse or, in the most serious cases, die. Newer tests that can detect staph DNA in a matter of hours are available, but they're more expensive than culture tests and not yet widely used.

What about Treatment?
MRSA may be treated with an antibiotic called vancomycin or with other antibiotics that have proved to work against certain strains. A few cases of vancomycin-resistant MRSA have already been reported too. To help reduce that threat, doctors try to limit the use of antibiotics, and vancomycin in particular, to situations where it's truly necessary. Some newer antibiotics are now available as staph infection treatment, but most are prohibitively expensive, and resistance to them has already developed.

How do I protect myself from getting an infection?
Now your getting smart. Protection from infection is the best prevention you can do. Protecting yourself from staph infections can seem impossible, given how widespread bacteria have become. But these common-sense precautions can help lower your risk:

• Wash your hands (wow, mom was right!). Careful hand washing is your best defense against germs. Scrub hands briskly for at least 15 to 30 seconds. If there is no soap and water, you can use a hand sanitizer containing at least 62 percent alcohol. These sanitizers are convenient and may actually kill more germs than soap and water do.
• Keep wounds covered. Keep cuts and scrapes clean and covered with sterile, dry bandages until they heal.
• Keep personal items personal. Avoid sharing personal items such as towels, sheets, razors, clothing and athletic equipment (this time, mom wasn’t exactly right with that sharing thing!) Staph infections can spread on objects as well as from person to person. If you have a cut or sore, wash your towels and linens using detergent and hot water with added bleach and dry them in a hot dryer.
• Get tested. If you have a skin infection that requires treatment or are scheduled for surgery, ask your doctor if you should be tested for MRSA.