In the closing decade of the last century, we saw warnings that
infectious diseases will require much more attention from patients and
physicians in the 21 st century. Recently d- covered diseases such as
AIDS pose a major threat to the population at large, and to that threat
has been added the re-emergence of established pathogens, microbes that
were re- ily treatable in the past. Since infectious diseases already
play a major role in the burden of illness and mortality, health care
providers and planners are worried. A large proportion of the problem is
man-made, arising mainly from the unnecessary overuse of antimicrobials
in hospital and community settings and from the agricultural misuse of
the agents in animal feed. A consequence has been a dramatic increase in
resi- ant strains of bacteria that were considered conquerable several
decades ago. Community infections caused by multi-resistant pneumococci
serve as an example. These organisms were readily treated with
penicillin, but now the spread of penicillin-resistant Streptococcus
pneumoniae from continent to continent is becoming a worldwide problem.
This is a major concern because pneumococcal infections are common in
the community, being the le- ing cause of pneumonia, sinusitis, and
meningitis. Resistant bacteria in hospitals are also becoming more
prevalent. We have become accustomed to hearing about methicill-
resistant Staphylococcus aureus (MRSA) and vancomycin-resistant
enterococci (VRE), but now we have to be concerned about
multidrug-resistant coliform bacteria and pseudomonads.