Garden-variety staph are common bacteria that can live in our bodies. Plenty of healthy people carry staph without being infected by it. In fact, one third of everybody has staph bacteria in their noses.
But staph can be a problem if it manages to get into the body, often through a cut. Once there, it can cause an infection. Staph is one of the most common causes of skin infections in the U.S. Usually, these are minor and don't need special treatment. Less often, staph can cause serious problems like infected wounds or pneumonia.
Staph can usually be treated with antibiotics. But over the decades, some strains of staph -- like MRSA -- have become resistant to antibiotics that once destroyed it. MRSA was first discovered in 1961. It's now resistant to methicillin, amoxicillin, penicillin, oxacillin, and many other common antibiotics.
While some antibiotics still work, MRSA is constantly adapting. Researchers developing new antibiotics are having a tough time keeping up.
You’re at an increased risk for HA-MRSA if you:
You’re at an increased risk for CA-MRSA if you:
Symptoms of HA-MRSA
HA-MRSA is generally more likely to cause serious complications, such as pneumonia, urinary tract infections, and sepsis. It’s important to see your doctor right away if you notice any of the following symptoms:
Symptoms of CA-MRSA
CA-MRSA usually causes skin infections. Areas that have increased body hair, such as the armpits or back of the neck, are more likely to be infected. Areas that have been cut, scratched, or rubbed are also vulnerable to infection because your biggest barrier to germs — your skin — has been damaged.
The infection usually causes a swollen, painful bump to form on the skin. The bump may resemble a spider bite or pimple. It often has a yellow or white center and a central head. This may often be surrounded by an area of redness and warmth, known as cellulitis. Pus and other fluids may drain from the affected area. Some people also experience a fever.
Diagnosis begins with a medical history assessment and physical examination. Samples will also be taken from the site of infection. The types of samples obtained to help diagnose MRSA include the following:
Wound samples are obtained with a sterile cotton swab and placed in a container. They’re then taken to a laboratory to be analyzed for the presence of staph bacteria.
Sputum is the substance that comes up from the respiratory tract during coughing. A sputum culture analyzes the sputum for the presence of bacteria, cell fragments, blood, or pus.
People who can cough can provide a sputum sample easily. Those who are unable to cough or who are on ventilators may need to undergo a respiratory lavage or bronchoscopy to obtain a sputum sample. Respiratory lavage and bronchoscopy involve the use of a bronchoscope, which is a thin tube with a camera attached. Under controlled conditions, the doctor inserts the bronchoscope through your mouth and into your lungs. The bronchoscope allows the doctor to see the lungs clearly and to collect a sample of fluid for testing.
In most cases, a sample for a urine culture is obtained from a “midstream clean catch” urine specimen. To do this, urine is collected in a sterile cup during urination. The cup is then given to the doctor, who sends it to a lab for analysis. Sometimes, urine has to be collected directly from the bladder. To do this, the healthcare provider inserts a sterile tube called a catheter into the bladder. Urine then drains from the bladder into a sterile container.
A blood culture requires the removal of a small sample of blood. Blood is then placed on a dish in a laboratory and allowed to grow bacteria that may be present within it. Results from blood cultures typically take about 48 hours. A positive test result can indicate sepsis, a type of blood infection. Bacteria can enter the blood from infections located in other parts of your body, such as the lungs, bones, and urinary tract.
HA-MRSA and CA-MRSA infections are typically treated differently.
HA-MRSA infections have the capability of producing severe and life-threatening infections. These infections usually require antibiotics through an IV, sometimes for long periods of time depending on the severity of your infection.
CA-MRSA infections will usually improve with oral antibiotics alone. If you have a large enough skin infection, your doctor may decide to perform an incision and drainage. This procedure is typically performed in an office setting under local anesthesia and involves using a scalpel to cut open the area of infection and drain it completely. You may not need antibiotics if this is performed.
Take the following measures to reduce your risk of getting and spreading CA-MRSA:
People with HA-MRSA are typically placed in isolation temporarily until their infection improves. Isolation prevents the spread of this type of MRSA infection. Hospital personnel caring for people with MRSA have to follow strict handwashing procedures. To further reduce their risk for MRSA, hospital staff and visitors should wear protective garments and gloves to prevent contact with contaminated surfaces. Linens and contaminated surfaces should always be properly disinfected.