Superbugs in America: Why MRSA is so Dangerous

Page content

What are Superbugs?

You may have heard of superbugs in America on the evening news or in your local paper. The medical community is extremely worried about superbugs, but what are they exactly? The term “superbug” refers to strains of bacteria that have become resistant to common antibiotics. This makes them extremely difficult to treat and can turn simple infections into life-threatening illnesses. A 2007 report in the Journal of the American Medical Association found that in the United States alone, 94,360 patients were infected with an antibiotic-resistant strain of bacteria. Of those patients, 18,650 of them died.

Put another way, one in five patients infected with a superbug died. A chilling fact to be sure.

History of Superbugs

Bacterial strains have not always been resistant to antibiotics - quite the opposite, in fact. When penicillin was first discovered in the 1940s, common strains of Staphylococcus aureus (more commonly known as “staph”) were easily treated with penicillin. Today virtually all strains are resistant to penicillin and common penicillin derivatives. These strains are called methicillin-resistant Staphylococcus aureus (MRSA) strains. Methicillin was historically a popular antibiotic used to treat staph infections and, for the first time, the medical community has noticed strains of bacteria becoming resistant. First noticed in 1961 at a British hospital, MRSA had spread worldwide by 1980. Today, superbugs in America and around the world are resistant to many more types of penicillin than just methicillin.

More frightening, a 2005 report in The Lancet Infectious Diseases medical journal estimated that nearly 69 percent of Staphylococcus aureus strains in American hospitals demonstrate multi-drug resistance to antibiotics. Soldiers returning from Afghanastan and Iraq are increasingly coming home with antibiotic-resistant superbugs due to wounds and triage administration of wide-spectrum antibiotics. There was even a case in 2000 where the Centers for Disease Control (CDC) investigated a MRSA outbreak on the St. Louis Rams football team.

What creates a Superbug?

While a superbug may evolve naturally, most superbugs become resistant due to inappropriate usage of antibiotics. It is not uncommon for patients to stop their antibiotic treatment early once their symptoms are gone. Thinking they are no longer sick, these patients save the rest of their antibiotics for a later date. This has two potential problems. Primarily, if the infection is not completely destroyed, a patient that stops their antibiotic schedule early has a good potential of creating a resistant strain. A small number of bacteria not killed by the antibiotic may have a slight natural immunity to the antibiotic. Given a few more days of treatment they would have died, but since the schedule was stopped short they are allowed to grow - creating a new strain of resistant bacteria.

The other problem is when patients inappropriately use antibiotics without consulting a medical professional. Perhaps a patient wakes up with a sore throat or nauseous stomach. Thinking they are clever or don’t have time to visit the doctor, the patient takes a few leftover antibiotics and goes to work. This tiny dose is not effective in clearing bacteria infections, and totally ineffective against viral infections. This inappropriate use does nothing more than select resistant strains of bacteria and cause further problems

In the next part of this series, we explore the genetics and molecular biology of superbugs such as MRSA and how medical professionals are trying to treat these resistant strains of staph infections.


  • Boyce, J. M., Cookson, B., Christiansen, K., Hori, S., Vuopio-Varkila, J., Kocagöz, S., Öztop, A. Y., et al. (2005). Meticillin-resistant Staphylococcus aureus. The Lancet Infectious Diseases, 5(10), 653-663. doi:10.1016/S1473-3099(05)70243-7

  • Nordmann, P., Naas, T., Forineau, N., & Poirel, L. (2007). Superbugs in the coming new decade; multidrug resistance and prospects for treatment of Staphylococcus aureus, Enterococcus spp. and Pseudomonas aeruginosa in 2010. Current Opinion in Microbiology, 10(5), 436-440. doi:10.1016/j.mib.2007.07.004

  • Superbugs: Protecting the Power of Antibiotics. Center for Disease Control. Retrieved June 12, 2010, from

This post is part of the series: Superbugs in America

Superbugs are a growing threat to the well being of Americans. In this series we explore the genetics of why superbugs are so dangerous.

  1. Superbugs in America