[A few viral infections in the recent epidemiological evolution (author's transl)]

In the study we presented a few infections of viral etiology that showed evident epidemiological evolutions during the last ten years. We refered of a disease nearly eradicated, of one that can be eradicated, and of a group of infections that at present cannot be eradicated. The first is poliomyelitis, the second is measles, the third is represented by viral infections connected with the respiratory tract. As for the first disease, the sistematic immunoprophilaxis applyed in different countries of the world on one hand stopped the transmission of wild polioviruses and on the other created an immunological barrier in those countries where polio vaccination is maintained, as demonstrated by statistics revealing the absence or low incidence of this disease. As for the epidemiological evolution of measles, after considering the incidence due to age, environment, social-hygienic conditions, mortality etc..., we refered in particular of a vaccination that took place in USA where the disease decreased with 1968 then rised next year a pause of the vaccination program. A second cycle of vaccinations against measles revealed in 1972 a decrease of the disease this signifying the importance of the vaccination in stopping, reducing or modifying the epidemiology of measles. The epidemiological conditions of respiratory infections are completely different due to the variety of the etiological factors, the difficulty in preparing aspecific vaccines, and the impossibility in recognising clinical forms caused by these viruses. All these factors, impede, actually, a complete eradication.