When discussing the drug, the bug, and the host in the past, emphasis was laid mainly upon the interaction between antibiotics and bacteria or the reaction of the host to the invading organism. Today, however, standardized immunologic parameters are available for evaluating cellular and humoral responses and an increasing number of publications deal with the host reaction to the antibiotics administered. Some re searchers and clinicians felt that the time had come to bring together investigators studying the influence of antibiotics on the host-parasite relationship. The first section of this...