RESULTS: Tetanus sero -protection was found in 96% of children (95% CI: 94.6–97.4) with an average geometrical mean of tetanus antitoxine antibodies of 1.49 IU/ml. The protection level of the diphteria antitoxine antibodies was about 10% lower than the level of antitetanus sero -protection of 87.4% (95% CI: 86.1-88.7). The children vaccinated with DTP3 have a medium level of seroprotection , while those who received 4 doses of vaccine have 91.8%. The Bordetella pertussis antibodies were present at a protector level in 76.1% children (95% CI: 72.9-79.2). The humoral antimeasles immunity reaches an average of 55.6% protected children (95% CI: 52.1-59.2) for a level of seropositive values of 62%. The percentage of the children protected against hepatitis B virus (HBV) infection had an average value of 59.5% (95% CI: 57.1-63.1) while the seropositive value was estimated to be 71.9%. CONCLUSIONS: The specific immunity to tetanus in the children aged less than 5 years corresponds to the goal of the National Immunization Program, but it is lower for diphteria , measles and HBV indicating susceptibility to these diseases.