penicillin-resistant staph bacteria emerged as early as 1942. Today, virtually all Staphylococcus aureus are penicillin resistant.


Staph bacteria are commonly carried on the skin or in the nose of healthy people. MRSA—methicillin-resistant Staphylococcus aureus—is a type of staph that is resistant to antibiotics called beta-lactams. In the past the majority of MRSA infections occurred among patients in hospitals or other health care settings. But drug-resistant staph is also showing up in healthy people who have not been staying in a hospital. If common staph bacteria were to become resistant to all readily available antibiotics, the practice of medicine would change dramatically. Any surgery or invasive procedure could bring life-threatening complications. As was the case in the pre-antibiotic era, even the most minor cuts in the skin could prove fatal.


Though this discussion focuses on the evolving resistance of bacteria to antibiotics, the issue of antimicrobial resistance is actually much broader. The resistance of viruses such as HIV and influenza to antivirals and of protozoan parasites to antimalarial drugs is a huge problem around the globe. Microbes have the capacity to develop resistance, whether they are bacteria, viruses, or protozoa.

How to Protect Yourself

To avoid contracting an antibiotic-resistant infection:

  • Do not demand an antibiotic when a health care provider says it is not needed.

  • Do not take an antibiotic for a viral infection, such as the common cold.

  • If your health care provider prescribes an antibiotic for you, do not skip doses and do not save any for the next time you get sick. Complete the prescribed course of treatment, even if you are feeling better.

  • If you are a hospital patient or have a loved one in the hospital, make sure that you and the doctors, nurses, support staff, and all visitors wash their hands or use a hand sanitizer prior to touching the patient.

Chronic Illness and Cancer

In the United States, 70 percent of all deaths are due to chronic diseases. Until recently their biological causes were mostly unknown. Today, growing evidence suggests that infections are behind many chronic diseases once thought to be caused by genetic, environmental, or lifestyle factors.


The human papillomavirus (HPV), for instance, causes more than 90 percent of cervical cancer cases. The hepatitis B virus accounts for more than 60 percent of liver cancer cases. The hepatitis C virus causes cirrhosis, end-stage liver disease, and liver cancer. Human herpesvirus 8 causes Kaposi’s sarcoma, a malignant complication of AIDS. Helicobacter pylori, a spiral-shaped bacterium, is the agent of peptic ulcers and gastric cancer. These examples may be just the tip of the iceberg.

Helicobacter pylori.

Helicobacter pylori.



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