World Hmlth r 50thYeor, No. l, lonuory-Februory l99i Resistont slrsins of mrcroolgqnrsms locques L Aror

terial meningitis, puerperal fever, typhoid fever, syphilis and rheumatic There ore o greof number of fever. Antibiotic drugs have sharply complex mechonisms by reduced infant mortality and, by making it possible to prevent and which resistont stroins of treat infections, they have opened up bocteria evode destructton by the wonders of modern surgery and resuscitation techniques. ontibiotiu; it is o perfectly phenomenon noturol for o Evoding destrudion living orgonism to develop the Within a few years of penicillin first meons of survivolin o hostile being used, microbiologists realized that bacteria were able to protect themselves against antibiotics by developing some means of resis- tance. The staphylococci, for in- Sir Alexonder Fleming won the produced an enzyme called llBBl-1955) stance, Nobei Prize for h;s discovery of penicillin, ,,ir-;a uring one of his lectures at the penicillinase which was able to which wos lo revolulionize ond lhe prognosis of bocferiol diseoses. Phot'o: WHO. ' ; SColldge de in 1933, the inactivate penicillin. if :if 4i511nguished bacteriologi st I will not try to describe the Charles Nicolle declared: "Infectious complex mechanisms that resistant tant to us all. When a strain of disease carries all the characteristics bacterial strains use to evade destruc- bacteria proves resistant to an antibi- oflife itself; it derives those charac- tion by antibiotics. Suffice it to say otic that is habitually used in treat- teristics both from its own nature and that there are a greatnumber of such ment, the physician is obliged to from its target - the living host." mechanisms and that it is a perfectly look for a radically different ap- The agents that cause disease are natural phenomenon for a living proach. A bacterial strain that is of different types. The most numer- organism to develop the means of resistant to several antibiotics is an ous are bacteria, viruses, parasites survival in a hostile environment. even harder problem to solve. and fungi. Some of these disease This is a normal process that takes Furthermore, a strain of bacteria agents are capable of triggering place equally among bacteria that are that is resistant to several antibiotics disease when they penetrate the pathogenic in animals and human survives more readily in a setting human organism and multiply there. beings, and among bacteria that are where antibiotics are frequently Such infections can be cured by the not pathogenic in the environment, used. This is so in hospitals, for natural defences of the patient's plants, animals or human beings. instance, where bacterial strains are body, helped by drugs (where they The fact is that antibiotics are first usually resistant to most of the exist) that destroy the microbes and foremost natural substances antibiotics currently in use. Bacteria within the body. produced from fungi or bacteria and are most frequently spread by one It was penicillin, discovered by only secondarily are they drugs that person contaminating another, which in 1928, which are developed and improved by our is how epidemics start. The more ushered in the antibiotic era. The chemists. resistant the bacteria and the more discovery of antibiotics revolution- Because they have been so widely capable they are of surviving against ized medicine and the prognosis of used in treating diseases in human the antibiotic in use, the more they bacterial diseases. At last a simple beings and in farm animals, antibi- can spread. This is why it is very cure was available for infectious otics have triggered the evolution of important to be alert to the develop- diseases that would otherwise have resistant bacteria all over the world. ment of resistance among the strains been fatal or would have left chronic The medical consequences of this ofbacteria that can cause serious after-effects - diseases such as bac- evolution are, of course, very impor- epidemics. WorldHeolth r 50lhYeor, No. l, Jonuory-Februory1997 t5

WHO Surveillonre nelwork Recognizing the emergence ond spreod of bocteriol stroins resistont to ontimicrobiol ogents os o prioriiy problem, the World Heolth Orgonizotion is reinforcing its octivities to improve surveillonce of ontimicrobiol resislonce ot nolionol ond globol levels. This surveillonce network will provide continuos informotion on ontibiotic resistonce to heolth core speciolists ond drug developers ond will serve os o worning system on the Where onfibtolrcs ore frequenily used, such os in hospilols, o bocteriol stroin resistont to severol emergence of resistont stroins. anfibiol;cs survives more ss5ily. Pholo: Keys/one @. Doto occumuloted within the surveillonce system will offer It is also possible for a resistant which they are indicated, and only guidonce on the development bacterial strain to spread resistant when they are prescribed by a physi- ond use of new ontibiotics ond genes in the form of plasmids or cian. It is a practice that aims to limit recommend woys to preserve transposons which are able to pene- the development of resistance to the efficocy of old ones. trate quite different species of bac- antibiotics as much as possible with- teria. This process is known as out depriving those patients for horizontal dissemination of resistant whom antibiotics are necessary. This genes. is a far-reaching task; it calls for obliging us to look at them ln a new close cooperation between physi- light. Take for example the case of cians, their patients, the public au- the parasite becoming resis- Good medirol Procti(e thorities, the pharmaceutical industry tant to chloroquine, the resistance of The medical consequences of anti- and basic research. fungi to antifungals, and above all biotic resistance in the agents that Resistant strains of bacteria have the resistance of viruses to antivirals cause disease have grown more attracted a great deal of attention in - herpes and the human immunode- serious in recent years, just as the the medical literature. The tubercu- ficiency virus (HIV) are only the number of newly developed anti- losis bacilli, the pneumococci and the first of a long list. biotics has diminished and their cost dysentery bacilli are major examples. Every time an effective treatment has risen. "Good usage ofanti- Yet all living organisms that are able is discovered against an infectious biotics" means using antibiotics only to cause infection are also able to organism, there will be a price to pay in the treatment of those diseases for develop resistance mechanisms, thus in terms of the eventual development of resistance. This is the dynamic of life which Charles Nicolle sought to underline. It is our responsibility to develop sensible strategies for the use of antibiotics and to improve our surveillance systems in ways that will keep the resistant strains of bacteria under control. I

Dr Jocques F. Acor is Professor of Medicol Microbiology of the Universil6 Pierre et Morte Curie, Fondotion H6pifol Sotntloseph, 185 Doses musl be corefully counted out: uncontrolled use of ontibiofics con leod to fhe development of rue Roymond Losserond, 75674 Poris Cedex drug resislonce. Photo: Still Pictures/P. Chondro @. 14, Fronce.