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The National Academies: What You Need To Know About Infectious Disease

What You Need To Know About Infectious Disease


MRSA, or methicillin-resistant Staphylococcus aureus, is a type of staph bacteria that is resistant to many of the antibiotics commonly used to treat ordinary staph infections. Although at one time MRSA infections were confined to people in health care settings, in recent years they have become more prevalent among healthy people in the community. MRSA is largely the result of decades of over-prescribing antibiotics. The potential for common bacterial infections to become resistant to readily available antibiotics is a scary thought and could change the practice of medicine significantly. Therefore, it is essential that everyone works together to avoid unnecessary antibiotic use and to practice hygiene to prevent MRSA infections in hospital settings and in the community.

MRSA infections originally only affected people in health care settings, such as hospitals or nursing homes. Patients in these facilities typically have weakened immune systems, and they may be undergoing procedures that make it easier for MRSA to enter the body, such as surgery or the insertion of catheters. MRSA infections are often severe, which is why health care personnel must follow strict procedures about hand washing and catheter care.

MRSA infections now also occur in the community at large. In those instances, they typically take the form of skin infections and are most likely to be spread in places where people are in close contact with each other, such as schools, locker rooms, and correctional facilities. The biggest risk factor is open or broken skin. However, MRSA infections can occur even on areas of the skin where there is no visible wound or break. In addition, MRSA can get into small openings in the skin, such as the openings at hair follicles.

MRSA infections can occur in any geographic area and anywhere on a person’s body. The MRSA bacteria tend to reside on people’s bodies and are not naturally found in the environment—that is, for example, not in soil, the ocean, or lakes. Objects can be contaminated if someone touches infected skin or areas of the body where these bacteria can live, such as the nose, and then touches the object. People may become infected by touching these surfaces but not in all instances. Direct contact with a person’s skin infection is another way that MRSA can spread.

In health care settings, MRSA infections tend to be more severe, causing life-threatening illnesses such as bloodstream infections, surgical site infections, and pneumonia. Symptoms can vary widely, depending on what form of infection is taking place and what stage it is in. Outside of health care settings, MRSA typically causes skin infections. These may first appear as small red bumps resembling pimples, boils, or spider bites. They can rapidly turn into deep, painful abscesses that require surgical draining. The bacteria may remain in the skin but sometimes it moves deep into the body, causing potentially life-threatening infections in bones, joints, surgical wounds, the bloodstream, heart valves, and lungs. MRSA skin infections commonly occur where there has been visible skin trauma—cuts or scrapes, for example—and on areas of the body covered by hair, such as the back of neck, groin, buttock, armpit, or beard area of men.

MRSA bacteria still respond to certain antibiotics. As with regular staph infections, recognizing and treating MRSA infections early reduces the risk of severe infection. Treatment will vary depending on the location of the infection and its severity. Treatment of skin infections may include draining the infection and an antibiotic prescription. Those who suspect they might have a MRSA skin infection should not attempt to treat it themselves. If you are given an antibiotic, be sure to finish the entire course unless told otherwise by your physician. It is possible to get repeat infections; once you have had a MRSA infection it does not mean you are immune to future infections.

Personal hygiene can help prevent MRSA skin infections. Keep hands clean by washing thoroughly with soap and warm water or with an alcohol-based hand sanitizer. Keep cuts and scrapes clean and covered until healed. Avoid contact with other people’s bandages. Avoid sharing personal items such as towels and razors. Use a barrier, such as clothing or towels, between you and any surfaces you share with others, such as gym equipment, and shower immediately after activities that involve direct skin contact with others. These are easy ways to decrease your risk of getting MRSA. 

Additional preventive measures are recommended for health care settings, athletic environments, and correctional facilities.  


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What do you know about infectious disease?

Which reproduce the fastest:

  • Sorry, that’s incorrect.

    Viruses reproduce the fastest. Humans produce a new generation every 20 years or so; bacteria do it every 20 to 30 minutes, and viruses even faster.

  • Sorry, that’s incorrect.

    Viruses reproduce the fastest. Humans produce a new generation every 20 years or so; bacteria do it every 20 to 30 minutes, and viruses even faster.

  • Correct!

    Viruses reproduce the fastest. Humans produce a new generation every 20 years or so; bacteria do it every 20 to 30 minutes, and viruses even faster.

Infectious Disease Defined

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