[Historical aspects of some infectious diseases: is their gradual eradication utopian?].

Infectious microorganisms (parasites, bacteria, viruses) which caused dramatic epidemics in human populations throughout the centuries, as well as their natural reservoirs and possible vectors, have not disappeared... Plague, cholera, malaria, tuberculosis, rickettsioses are still quite present in some areas of the world. Furthermore new infectious diseases caused by emerging pathogens have recently appeared dramatically, such as AIDS. Eradication of the most severe and lethal infectious diseases remains nevertheless an ambitious but not utopian objective, if one considers the spectacular advances made, more or less recently, in the field of specific vaccinations. For instance, smallpox has been eradicated around 1980. Present efforts are mainly concentrated on poliomyelitis, the eradication of which was hoped to take place in year 2005, but which is still present in a few areas. Eradication of measles, with the presently available vaccine, is a reasonable objective. Eradication of malaria appears to be much more difficult since this infection involves a complex parasite and an insect vector, the mosquito. And, as far as AIDS is concerned, intensive research has not yet led to the conception of an effective vaccine.