Staph among us

Thirty percent of the population at any one time carries colonies of staphylococcus aureus on their skin and in their nose.

One percent carries colonies of the antibiotic-resistant version of the bacteria that recently infected students in Anne Arundel County, Md., and Rappahannock County, Va., public schools.

Carrying the bacteria known as staph is common, but it usually doesn’t lead to an infection, area doctors say.

“Colonization is to have staph on our skin without any symptoms,” says Dr. Jose Bordon, associate director of the Internal Medicine Residency Program, Section of Infectious Diseases, at Providence Hospital in Northeast. “However, colonized people are carriers and the source of staph spreading in the community,” he says.

Staph can enter the body through a cut, scrape or other wound or be transmitted by skin-on-skin contact with an infected person or contact with contaminated items and surfaces, according to a fact sheet provided by the Centers for Disease Control and Prevention (CDC) in Atlanta.

“It’s everywhere. It’s on counters. It’s on our skin,” says Dr. Georges Benjamin, executive director of the American Public Health Association, a membership organization of public health professionals based in Northwest. “What happens is, because it’s everywhere, if you get a cut or crack in your skin, or you’re ill and your resistance goes down, the organism has an opportunity to grow.”

Staph can appear as small red bumps that look like pimples, spider bites or boils, as abscesses that need to be drained surgically or as cellulitis, a type of infection that affects the skin’s deeper layers, according to metro-area physicians. In more severe cases, staph can cause blood-stream infections; damage bones, joints and organs; or lead to pneumonia, they say.

Staph infections are treated with oral or intravenous antibiotics or surgery, depending on the size and location of the infection, physicians say.

Methicillin-resistant staphylococcus aureus (MRSA) is a strain of staph that is resistant to penicillin, penicillin-derived antibiotics and cephalosporins, cousins to penicillin, says Dr. Shmuel Shoham, an attending physician in infectious diseases at the Washington Hospital Center in Northwest.

MRSA is treated with vancomycin and other antibiotics.

At first, MRSA was acquired only in hospitals and health care facilities as hospital-associated or HA-MRSA, Dr. Shoham says. In the 1990s, a strain of staph known as community-associated or CA-MRSA, began appearing in the larger community, he says.

“It’s not exactly clear what has led to the shift in the last few years,” Dr. Shoham says. “Sometimes, a mutation occurs in the DNA of staph to give it an advantage to survive in the presence of antibiotics, thereby reducing resistance.”

Unnecessary antibiotic use has led to staph’s increased resistance, says Dr. Anthony Harris, associate professor of epidemiology and preventative medicine at the University of Maryland School of Medicine in Baltimore.

“The problem that is arising with MRSA and other antibiotic-resistant infections is that the rates are skyrocketing, but the number of new antibiotics to treat this are diminishing,” Dr. Harris says.

The HA- and CA-MRSA strains differ in their resistance abilities but are beginning to merge, says Dr. Lewis Marshall, chief of infectious diseases at Providence Hospital.

“The organism is evolving based on this antibiotic pressure everywhere. Eventually, they will be more alike than different,” Dr. Lewis says.

Each year, the HA-MRSA strain is responsible for 300,000 to 400,000 staph infections, Dr. Benjamin says. The number of staph infections caused by CA-MRSA has not been determined, he says.

In Anne Arundel County, reports of staph infections have received media attention.

Three of the four Severna Park High School students diagnosed with staph the last week of September are athletes, says Bob Mosier, schools spokesman for Anne Arundel County Public Schools. That same week, the school learned of two separate adult cases that had occurred in June and August, he says.

“There is no way for us to know at this moment whether any or all of these cases are related and what the origins are of the cases,” Mr. Mosier says.

Anne Arundel County schools responded to the staph outbreak by disinfecting and cleaning the locker rooms and shower areas of the district’s 11 high schools with a hospital-grade detergent, as recommended by the health department, Mr. Mosier says.

Another 24 students from Severna Park, Glen Burnie, Old Mill and Chesapeake high schools reported staph infections in the past two weeks, Mr. Mosier says. Of the 28 reported infections, one is a confirmed case of MRSA, he says. Some of the reported cases are minor and occurred weeks or even months previously, he says.

Rappahannock County High School in Washington, Va., closed Wednesday to clean and disinfect the athletic areas of the school after a student football player was diagnosed with an MRSA infection the weekend before. School officials were notified of the diagnosis Oct. 9.

“We’re so small here, we decided to close our school to ensure the safety of our students,” says Robert Chappell, superintendent of schools for Rappahannock County Public Schools. He holds a doctorate in educational leadership.

Risk factors for getting the CA-MRSA strain include poor hygiene, living in close quarters and participating in contact sports, according to the CDC.

Some conditions that make people prone to acquiring either type of MRSA include a weakened immune system, poor blood glucose control and eczema, Dr. Shoham says.

Extremes of age, having a chronic disease, such as diabetes or kidney disease, and getting over a viral illness like pneumonia or influenza are additional risk factors, Dr. Benjamin says.

To prevent the spread of staph infections at schools and the community at large, Dr. Harris recommends scrubbing hands with soap and water for 30 seconds or using an alcohol-based hand sanitizer, along with covering any skin abrasions and avoiding sharing towels, razors and the like.