Getting the dirt on staph infections

This article originally appeared in the November 1 issue of the Wareham Courier.

WAREHAM - While there have been no medically confirmed cases of staph infections in the area, the bacterium is still a cause for concern in and out of Wareham's public schools.

Eight cases of methicillin resistant staphylococcus aureus (MRSA) in Massachusetts have landed in the news over the last few weeks, including several in Dartmouth and at least one apparent case at Wareham High School. According to Dr. Nancy Edwards, president of the medical staff for Tobey Hospital, the recent infections are part of an ongoing and worrisome rise of resistant strains of bacteria.

"It's been problematic in hospitals for about five years, and about three years ago, I started to read articles about [MSRA] in the community," she said.

Staph is a very common bacterium. Almost 30 percent of people carry a benign form of staphylococcus aureus on their skin or nasal passage without any serious effects because it is easy prey for antibiotics or vigorous scrubbing. MRSA is different because it spreads quickly and produces chemicals that can be very harmful to people if they enter the bloodstream or other vulnerable areas.

Unlike other forms of staph, it is also resistant to many different kinds of antibiotics, which makes it tricky to deal with since many patients are allergic to the few oral antibiotics that remain effective against the bacteria.

"I think it's something to be very concerned about because of the limited number of oral antibiotics that we use," Edwards said.

While resistant strains of bacteria used to be confined largely to patients at hospitals and nursing homes, now an estimated 1 percent of the total population - even people who are unconnected to healthcare facilities - carry the strain, and that number is sure to grow.

The rise of resistant strains of bacteria can be attributed to the widespread use of broad-spectrum antibiotics in both hospitals and the world at large. While the introduction of antibiotics was an incredible advance in medicine, Edwards said it may have been too much of a good thing, especially since doctors turned to the small number of antibiotics with abandon. That indiscriminant use of antibiotics has also spread to the consumer market. For a moment, try to list all of the products in medicine cabinets and on store shelves that have the word "antibacterial" emblazoned on them.

Bacteria are the most successful organisms on the planet, playing roles in ecosystems as diverse as deep-sea volcanic vents and the human digestive tract. One reason they're so successful is because of their adaptability. As simple organisms, their biology can be profoundly affected by even minute changes.

Since bacteria reproduce asexually, they don't have to spend a lot of time picking out and pursuing a mate; they eat until they grow large enough to split in two. In some cases, bacteria can double in less than 10 minutes, meaning that one bacterium can turn into more than 4,000 in as few as two hours if there's enough food around. If there's a one in a million chance that a bacterium will develop a beneficial mutation, then it's likely that one might appear after about three hours.

Cleaning a kitchen counter with an antibacterial soap will kill all of the bacteria except for the ones with a resistant mutation. Without any competition, the resistant bacteria will be able to repopulate the ecosystem. When the counter is wiped down again, antibacterial soap won't be very effective. The scenario is playing out well beyond kitchens and hospitals. As bacteria vulnerable to antibiotics are killed off, resistant strains swoop in and take advantage.

In most situations, these bacteria pose very little threat to the people they surround. Even still, harmful bacteria develop resistances in the same way, so now antibiotics are becoming less and less effective in treating illness caused by bacteria.

"The best prevention is not to seek antibiotics when they're not necessary," Edwards said.

Approximately 750,000 people die every year in the United States due to infections. The awareness of the effect of indiscriminate antibiotic use has led changes in protocol at hospitals when handling infection and wounds. Insurance companies have also changed their policies as a result. Medicare, for example, will not cover treatment for infections that result from in-hospital procedures.

"If you let the infection get too far ahead of you, then someone can lose their life," Edwards said.

Wareham High School placed an alcohol-based sanitizer in classrooms and wiped down commonly handled surfaces like doorknobs with a bleach solution designed to kill bacteria without using antibiotics. Still, strict hand washing is the best way to help stave off infection. For more information, visit www.southcoast.org/health/mrsa.