Antibiotic synergy with enterococcal endocarditis experienced a high relapse rate when penicillin G alone was used for treatment and a demonstrably lower relapse rate when streptomycin was combined with penicillin G to combat the infection. Since that time the research community has conducted numerous studies regarding the effects and possibilities of antibiotic combinations. Today, combination therapy is recognized as providing a broad spectrum of antibiotic coverage, effectively fighting polymicrobial infections, minimizing selection for antibiotic resistant strains, lowering dose toxicity where applicable, and in some cases providing synergistic activity. Antibiotic synergy is desirable in a clinic sense for several reasons. At the patient
Antibiotic use in livestock common foods harboring these pathogens. There is evidence that a large proportion of resistant "E. coli" isolates causing blood stream infections in people are from livestock produced as food. When manure from antibiotic-fed swine is used as fertilizer elsewhere, the manure may be contaminated with bacteria which can infect humans. Studies have also shown that direct contact with livestock can lead to the spread of antibiotic-resistant bacteria from animals to humans. Sampling of retail meats such as turkey, chicken, pork and beef consistently show high levels of Enterobacteriaceae. Rates of resistant bacteria in these meats are high as well. Sources