Is it really a spider bite or a staph infection?

Is that red bump a spider bite or could it be a staph infection caused by methicillin-resistant Staphylococcal aureus (MRSA)? MRSA, a newer type of staph infection, has been present in Iowa since at least the late 1990s. Across the country, MRSA has been a reported cause of healthcare associated infections since the 1960s. This newer type of MRSA affects otherwise healthy people and is often called community-acquired MRSA (CA MRSA).

Staphylococcus aureus, "staph," is a bacterium that is commonly found on the skin or in the nose of healthy people. Experts agree that about 25 percent to 30 percent of the general population is colonized with staph in the nose. This means that the bacteria is present but does not cause an infection. Staph bacteria are one of the most common causes of skin infections. Most of these skin infections are minor and appear as a small pimple or boil. They usually go away without any treatment. Staph bacteria can cause much more serious infections. These more serious infections can be found in surgical wounds, as a bloodstream infection, or as a pneumonia.

Staph infections, including MRSA, occur most frequently in people who have been recently hospitalized, in individuals who live in nursing homes, or in patients of dialysis centers. In recent years, healthcare providers are seeing individuals who have contracted MRSA who have not been hospitalized recently, do not live in a nursing home, and are not dialysis center patients. These "community-acquired" infections often start as a skin infection in normally healthy people. In fact, many individuals report that they think the simple wound is from a recent spider bite or that it might be a pimple or boil.

Across the country, MRSA infections are becoming the most common cause of skin and soft-tissue infections coming to emergency rooms, according to an August issue of the New England Journal of Medicine. The researchers reported that "Community-acquired MRSA most often manifests itself on the skin as a boil or pimple that can be swollen, red and painful, and have drainage. Patients with MRSA are likely to think that a spider bite is the reason for a skin lesion in the absence of other skin problems."

There have been outbreaks of community-acquired MRSA reported in athletes, prisons and jails, military recruits, children and others across the county in recent years. Reports of athletes with skin lesions related to MRSA have occurred in Iowa. The Centers for Disease Control (CDC) has issued recommendations for preventing skin infections among sports participants in school settings. The Iowa High School Athletic Association has a skin condition report for wrestlers on their Web site.

There are some basic measures that individuals can take to protect themselves and to lessen the risk of MRSA infection. They include:

- Keep your hands clean. Wash your hands thoroughly with warm, soapy water. Use an alcohol-based hand sanitizer if soap and water are not available.

- Keep cuts and scrapes clean and covered with a bandage until healed.

- Avoid contact with other people"s wounds or bandages.

- Avoid sharing personal items such as towels and razors with others.

Any "spider bite" or other type of skin lesion that is not healing should be checked by a doctor or other healthcare provider.

Most staph infections can be successfully treated with common antibiotics as prescribed by a health care provider. Methicillin-resistant Staphylococcus Aureus (MRSA) is a type of staph that is resistant to certain antibiotics. These antibiotics include methicillin and other more common antibiotics such as oxacillin, penicillin and amoxicillin. Treatment of MRSA infectious can be more difficult because of antibiotic resistance.

If you are diagnosed with a staph or MRSA infection and you are given an antibiotic, it is important to take all of the doses of the medication, even if the infection is getting better. You should take all of the prescribed antibiotic unless your doctor tells you it is OK to stop taking it. Do not share your antibiotic with other people or save unfinished antibiotics for use at another time.

Some staph infections may be treated by draining the abscess or boil and may not require antibiotic medications. Drainage of skin abscesses or boils should only be done by your doctor or other health care provider. Follow directions for care of the abscess or boil as given to you by your health care provider. If the infection does not seem to improve after a few days or if other people you know or live with get the same infection, it is important to contact your health care provider.

For more information on MRSA and community-acquired MRSA, go to http://www.cdc.gov/ncidod/dhqp/ar_mrsa.html.

(Sources: Iowa Department of Public Health, CDC)