• Infectious Diseases
• Wounds and Healing
• Pharmacology

• Bacteria
• Microbes and More
• Microbiology

• Penicillin-like antibiotics
• Upper respiratory tract infection
• Pathogen
• Antiviral drug

BACKGROUND: A microbe called methicillin-resistant Staphylococcus aureus (MRSA) is a common cause of skin infections; it can also cause pneumonia, ear infections and sinusitis. Such infections were once only found in hospitals and prisons; patients with deep wounds and IV catheters, for example were at particular risk of infection. However, now that athletes are in such close contact with one another and share Jacuzzis, whirlpools and athletic equipment, this microbe is proliferating in locker rooms at all levels of sports. The Washington Redskins and other NFL teams are using science and better strategies to beat back the bug. MRSA bacteria are sometimes dubbed "superbugs" because they are highly resistant to common antibiotics like penicillin, making infections difficult to treat effectively.

HOW ANTIBIOTICS WORK: Infections are caused by single-celled organisms called bacteria, which can sometimes evade the body's immune system and begin reproducing. Antibiotics kill those harmful bacteria in various ways, such as preventing a bacterium from turning glucose into energy, or preventing it from construct a cell wall. The bacteria die instead of reproducing. Antibiotics are like selective poisons, because they target bacteria and not the body's own cells. They are not effective against viruses, however. Unlike bacteria, a virus isn't a living, reproducing lifeform, just a piece of DNA or RNA. A virus injects its DNA into a living cell and the cell itself reproduces more of the viral DNA. There is nothing to "kill," so antibiotics don't work on viruses.

DRUG RESISTANCE: Bacteria are highly adaptive, and over time they naturally develop resistance, protecting them incoming germs (and antibiotics) and making them harder to kill. Repeated exposure to penicillin and amoxicillin can result in a throat full of bacteria that can shield germs from the older drugs. These "co-pathogens" become more dominant. Sometimes people discontinue antibiotic medication prematurely when they begin to feel better, so the germ isn't entirely killed off.

The American Society for Microbiology contributed to the information contained in the TV portion of this report.

Editor's Note: This article is not intended to provide medical advice, diagnosis or treatment.