The National Institute of Allergy and Infectious Diseases reports that many common infectious agents have become an increasingly worrisome public health threat. A strain of tuberculosis has developed a resistance to most drug therapies and is now known as MDR-TB, or multi-drug-resistant tuberculosis.
Some strains of staph have developed a level of resistance to the powerful antibiotic vancomycin, once the last defense against the bacteria. But after use of vancomycin became widespread, the staph bacteria mutated to a strain named VRSA, or vancomycin-resistant Staphylococcus aureus.
VRE, or vancomycin-resistant enterococci, a bacteria that infects the urinary tract, wounds and other areas, has also grown resistant to the antibiotic.
A common bacteria known as Acinetobacter has mutated into a few antibiotic-resistant strains found more frequently in hospital settings. These strains can cause severe blood stream infections, pneumonia, skin and wound infections, and meningitis.
And throughout the world, strains of malaria, salmonella and cholera have arisen that can resist the most potent weapons that drugs companies can develop. Malaria alone kills an estimated 1 million people each year.
In the United States, infectious diseases like these are the third-leading cause of death -- they are the second-leading cause of death worldwide.
Experts note that the casual use of antibiotics for everything including the flu and the common cold -- against which antibiotics are useless -- is fueling the rise of antibiotic-resistant bacteria. Even antibacterial soaps containing triclosan have come under fire for creating an environment where triclosan resistant bacteria can flourish.
The CDC notes that all soaps are antibiotic in nature. Antibacterial soaps have in fact been associated with an increase in bacteria on nurses' hands due to the skin damage these soaps can cause.
Officials at the CDC say there are many steps that can be taken to ward off these types of infections, even when faced with the most virulent forms of bacteria.
"These infectious agents are resistant to some of our strongest drugs, but they do not resist hand washing," said Dr. Dan Jernigan, a medical epidemiologist with the CDC. "It's funny that even with the technology we have, the simple interventions ... remain the most effective way to prevent disease."
In addition to regular hand washing with plain soap, the CDC recommends keeping cuts and abrasions clean and covered with a bandage until they're healed, and avoiding contact with other people's wounds or material contaminated from wounds.
But even our strongest medical and social defenses may not prevent the spread of bacterial and viral infections. Joshua Lederberg, a Nobel Prize-winning geneticist, wrote in an April 2000 article in the journal "Science" that the ease of international travel, human encroachment into wilderness areas and urban crowding will continue to provide opportunities for the spread of infectious diseases.
And microbes, Edwards noted, have been around for 3.5 billion years (compared to a mere 4.5 million years of human evolution). They can thrive in oxygen-free environments, in boiling water, in solid rock and in ice.
"The future of humanity and microbes likely will unfold," Lederberg wrote, "as episodes of a suspense thriller that could be titled 'Our Wits Versus Their Genes.' "
This article is the first of a three-part series.