Historically, several people died from infections caused by various species of bacteria, fungi, viruses, protozoa and other parasites. The discovery of antimicrobials, especially the antibiotics (antibacterial agents) revolutionised management and treatment of infectious diseases. Taking the antibiotics for example, the discovery of the penicillins by Alexander Fleming in 1928 brought relief to many who suffered from bacterial infections. It was not until 1945 that the penicillins were produced in commercial quantities to combat infections caused by Staphylococcus aureus and other bacteria. Though penicillin, as it were, was not the first antibacterial agent discovered, its serendipitous discovery from another microorganism (mould) gave hope that other classes of antimicrobials could be obtained from such sources. Indeed, research in finding more antimicrobials from other microbial (mainly fungal) sources intensified, and this led to discovery (originally) of many classes of antimicrobials including the cephalosporins, aminoglycosides, tetracyclines, chloramphenicol.