This seems like an age of miracle drugs.
Few weeks go by without a news story heralding a promising new drug or drug therapy.
Ironically, concealed in the din of information about new drugs looms a health crisis growing out of the loss of old drugs. Once a storehouse full of medicines such as penicillin and streptomycin could handily fight off most infections from bacteria and other microorganisms. Now, once-vulnerable bacteria have evolved resistance, and many of these drugs are losing their effectiveness. Some strains of tuberculosis, for example, are now resistant to all available antimicrobial drugs. Unfortunately, tuberculosis is not the only resistant microorganism on the public health horizon.