Doctors have noticed a rise in cases where antibiotics that were once used successfully to treat patients with bacterial infections now have little or no effect. The reason for this increased resistance is the abuse of antibiotics in the healthcare and farming industries. Antibiotics have been overprescribed by doctors, but they are also frequently added to animal feed in order to prevent disease but also to speed up animals' growth rate. Both practices have encouraged the harmless but naturally-resistant bacteria that survive in the human or animal to grow stronger and more numerous. This is not problematic until the harmless bacteria encounters a harmful, disease-causing bacteria. At that point, however, it passes on its drug-resistant capabilities to produce a potentially very dangerous type of bacteria.
The Methicillin-resistant Staphylococcus aureus bacteria, or MRSA, is a particularly serious example because it is highly contagious and can even be transmitted from animals to humans. Medical staff are taking measures to limit the harm it can cause by isolating patients carrying the bacteria in special wards to prevent its spread and further resistance development. Many hospitals have also instituted strict hand-washing and glove-wearing policies to minimize the risk of employees accidentally infecting patients as they move from room to room. The antibiotics that remain effective against MRSA are few in number; they are also much more expensive than simpler varieties and can produce unpleasant side effects. For all of these reasons, doctors want to reduce cases of the disease by any other means to avoid using the now-precious antibiotics wherever possible.