The seroepidemiology of varicella in Italy

We conducted a seroepidemiological study to evaluate the potential impact o f mass varicella vaccination on the transmission of varicella-zoster virus (VZV) in Italy, where vaccination is not mandatory. We tested 3179 serum sa mples, collected from September 1996 to October 1997, for specific anti-VZV antibodies using a commercially available ELISA. The results confirmed tha t varicella typically involves children (82(.)1% seroprevalence among 10- t o 14-year-olds) and that the mean age of acquiring the infection seems to b e increasing. The results also revealed that southern Italy, compared to th e rest of the country, has a greater circulation of VZV and an earlier age of acquisition. The potential impact of mass vaccination among 12- to 18-mo nth-old children on the epidemiological trend of the infection must be care fully considered, in that failure to reach high levels of coverage could le ad to an increase in the mean age of acquisition, which is already occurrin g in Italy.