ABSTRACT

As a result of the wide use of antibiotics, doctors are encountering more and more multidrug-resistant (MDR) bacteria. This problem involves methicillin-resistant staphylococci (e.g., Staphylococcus aureus), penicillinresistant streptococci (e.g., Streptococcus pneumoniae), vancomycin-resistant enterococci (e.g., Enterococcus faecalis), ß-lactamase-producing enteric bacteria (e.g., Escherichia coli, Salmonella spp., Klebsiella spp.), as much as multiresistant strains of Mycobacterium tuberculosis and Pseudomonas aeruginosa. In addition, the emergence of virus strains resistant to commonly used antiviral drugs is also becoming a worldwide problem particularly in immunocompromised patients (Bacon et al. 2003, Morfi n and Thouvenot 2003).