ATTEMPT TO CHECK THE EFFECTIVENESS OF VACCINATION AGAINST POLIOMYELITIS AS A CURRENT ANTIEPIDEMIC PRACTICE.
D002648:Child; D003604:Czechoslovakia; D006801:Humans; D007223:Infant; D011051:Poliomyelitis; D011055:Poliovirus Vaccine, Oral; D014611:Vaccination
D011055:Poliovirus Vaccine, Oral
CHILD; CZECHOSLOVAKIA; INFANT; POLIOVIRUS VACCINE, ORAL