An antibiotic-resistant organism is a bacterial life form with an ability to tolerate the antibiotics that are commonly used against it. Bacterial organisms adapt more quickly than other life forms. When they're exposed to something that harms them, like an antibiotic, many of them will be killed—some, however, may have a resistance, and those will quickly start self-replicating and spreading their genes throughout the colony.
What makes things even more dangerous is that they can often transfer genetic material from one species to another in a process called horizontal gene transmission. If one bacteria evolves a resistance to a particular antibiotic, it can pass that resistance along to a totally different species. Hospitals are one of the most common places for antibiotic-resistant organisms to propagate, so patients and medical personnel are at a greater risk than the general population.
Many scientists think that overuse of antibiotics is the major cause of antibiotic-resistant organisms. Since bacteria get so much exposure to drug treatments, they may be adapting even more rapidly than they normally would. When people develop any kind of infection, doctors are generally very quick to prescribe antibiotics, even when the case is relatively minor. Some scientists think this behavior pattern needs to be curtailed to protect people from a potentially dangerous situation.
One of the most significant fears is that some major diseases that have been controlled by antibiotics—tuberculosis is one example—may become antibiotic-resistant and endanger the public again. Some scientists estimate that as many as 70% of all bacteria have developed some kind of antibiotic-resistant ability, and many are resistant to more than one antibiotic. Already, several common illnesses have become more difficult to treat, including ear infections, pneumonia and infected wounds. Many experts expect this trend to continue, which could become very dangerous in a relatively short amount of time.
There's also a subset of scientists who feel the idea of curtailing antibiotic usage is somewhat unrealistic. They have focused on finding new antibiotics, so that many different drugs can be used in a cyclic manner. The general idea would be to lessen the exposure of organisms to particular drugs by constantly rotating and changing medications. Much research money has been expended in this area, and experts generally agree that a greater number of available antibiotics would be highly beneficial, even if it doesn't fix the problem completely.
