About MRSA and Staph

The name "Staphylococcus" comes from the Greek staphyle meaning a bunch of grapes and kokkos meaning berry, and that is what Staph look like under the microscope, like a bunch of grapes or little round berries. (In technical terms, these are gram-positive, facultative anaerobic, usually unencapsulated cocci.)

Over 30 different types of Staphylococci can infect humans, but most infections are caused by Staphylococcus aureus. Staphylococci can be found normally in the nose and on the skin (and less commonly in other locations) of 20%-30% of healthy adults. In the majority of cases, the bacteria do not cause disease. However, damage to the skin or other injury may allow the bacteria to overcome the natural protective mechanisms of the body, leading to infection.

Say no to anti-bacterial soaps

Anyone can develop a Staph infection, although certain groups of people are at greater risk, including newborn infants, breastfeeding women, and people with chronic conditions such as diabetes, cancer, vascular disease, and lung disease. Injecting drug users, those with skin injuries or disorders, intravenous catheters, surgical incisions, and those with a weakened immune system all have an increased risk of developing Staph infections.

What are the symptoms and signs of a Staph infection?

Staphylococcal disease of the skin usually results in a localized collection of pus, known as an abscess, boil, or furuncle. The affected area may be red, swollen, and painful. Drainage or pus is common.

What types of diseases are caused by Staph?

Staph infections of the skin can progress to impetigo (a crusting of the skin) or cellulitis (inflammation of the connective tissue under the skin, leading to swelling and redness of the area). In rare cases, a serious complication known as scalded skin syndrome (see below) can develop. In breastfeeding women, Staph can result in mastitis (inflammation of the breast) or in abscess of the breast. Staphylococcal breast abscesses can release bacteria into the mother's milk.

When the bacteria enter the bloodstream and spread to other organs, a number of serious infections can occur. Staphylococcal pneumonia predominantly affects people with underlying lung disease and can lead to abscess formation within the lungs. Infection of the heart valves (endocarditis) can lead to heart failure. Spread of Staphylococci to the bones can result in severe inflammation of the bones known as osteomyelitis. Staphylococcal sepsis (widespread infection of the bloodstream) is a leading cause of shock and circulatory collapse, leading to death, in people with severe burns over large areas of the body.

Staphylococcal food poisoning is an illness of the bowels that causes nausea, vomiting, diarrhea, and dehydration. It is caused by eating foods contaminated with toxins produced by Staphylococcus aureus. Symptoms usually develop within one to six hours after eating contaminated food. The illness usually lasts for one to three days and resolves on its own. Patients with this illness are not contagious, since toxins are not transmitted from one person to another.

Toxic shock syndrome is an illness caused by toxins secreted by Staph aureus bacteria growing under conditions in which there is little or no oxygen. Toxic shock syndrome is characterized by the sudden onset of high fever, vomiting, diarrhea, and muscle aches, followed by low blood pressure (hypotension), which can lead to shock and death. There may be a rash resembling sunburn, with peeling of skin. Toxic shock syndrome was originally described and still occurs especially in menstruating women using tampons.

MRSA, or methicillin-resistant Staphylococcus aureus, is a bacterium that can cause serious infections. It is resistant to numerous antibiotics of the beta-lactam family, including methicillin and penicillin.

MRSA belongs to the large group of bacteria known as Staphylococci, often referred to as Staph. About 25%-30% of all people have Staph within the nose, but it normally does not cause an infection. In contrast, only about 1% of the population have MRSA.

Infections with MRSA are most common in hospitals and other institutional health-care settings, such as nursing homes, where they tend to strike older people, those who are very ill, and people with a weakened immune system. In health-care settings, MRSA is a frequent cause of surgical wound infections, urinary tract infections, bloodstream infections (sepsis), and pneumonia.

MRSA outbreaks, however, are appearing increasingly in the community. Infections can occur in people who have not been hospitalized or had a medical procedure performed in the past year, and who do not have immune deficiency. These infections are termed community-associated MRSA infections (CA-MRSA). The U.S. Centers for Disease Control and Prevention (CDC) estimates that about 12% of MRSA infections are now community-associated, but this percentage can vary by community and patient population.

Personal experiences with staph: Symptoms and Treatments

Link to CDC (Centers for Disease Control) about MRSA and STAPH

The Mayo Clinic's Staph Page

What is antibiotic-resistant Staph aureus?

Methicillin-resistant staphylococcus aureus, known as MRSA, is a type of Staphylococcus aureus that is resistant to the antibiotic methicillin and other drugs in the same class, including penicillin, amoxicillin, and oxacillin. MRSA first appeared in patients in hospitals and other health facilities, especially among the elderly, the very sick, and those with an open wound (such as a bedsore) or catheter in the body. MRSA has since been found to cause illness in the community outside of hospitals and other health facilities. MRSA in the community is associated with recent antibiotic use, sharing contaminated items, having active skin diseases, and living in crowded settings. The U.S. Centers for Disease Control and Prevention (CDC) estimates that about 12% of MRSA infections are now community-associated, but this percentage can vary by community and patient population.

MRSA infections are usually mild superficial infections of the skin that can be treated successfully with proper skin care and antibiotics. MRSA, however, can be difficult to treat and can progress to life-threatening blood or bone infections because there are fewer effective antibiotics available for treatment.

The transmission of MRSA is largely from people with active MRSA skin infections. MRSA is almost always spread by direct physical contact and not through the air. Spread may also occur through indirect contact by touching objects (such as towels, sheets, wound dressings, clothes, workout areas, sports equipment) contaminated by the infected skin of a person with MRSA. Just as S. aureus can be carried on the skin or in the nose without causing any disease, MRSA can be carried in this way also.

More recently, strains of Staph aureus have been identified that are resistant to the antibiotic vancomycin, which is normally effective in treating Staph infections. These bacteria are referred to as vancomycin-intermediate resistance S. aureus (VISA) and vancomycin-resistant Staph aureus (VRSA).