Seroimmunity to polioviruses in an urban population of Italy

In a seroepidemiological survey on immunity to polioviruses, carried out in Rome, neutralizing antibodies were titrated on 602 serum samples collected from individuals aged from 6 months to 88 years. The geometric mean titres were 25.24, 25.92, and 18.12 for poliovirus types 1, 2, and 3, respectively. The number of seronegative results for each virus strain was very low (