Trends in meningococcal disease in Italy in 1986

In the epidemiologic year 1986 in Italy we observed a 27% decrease from the previous year in the incidence of meningococcal disease. The seasonal pattern showed that 73% of the cases occurred in the period January–May. The highest number of cases was seen in the 1–4 year-old age group (27.5%). The frequency in army recruits was 7/100,000 as opposed to 0.8/100,000 in the general population. Seventy-four percent of the isolates (95% among recruits) belonged to serogroup C while serogroup B constituted only 18%. Seventy-three percent of the serogroup C strains were serotype 2a. The proportion of strains resistant to sulphonamides was 69.4% and in contrast, only one strain was resistant to rifampin and three to minocyclin. Only two secondary cases occurred, both due to failure in the administration of chemoprophylaxis (sulphonamides). Our findings are consistent with the trends reported in Italy in 1985: predominance of serogroup C, high frequency of sulphonamide resistance, and high incidence among recruits with nearly all cases caused by serogroup C and therefore preventable by immunization. On the basis of these results, vaccination of army recruits against meningococcal disease has been made compulsory by law in Italy as of January 1987. Despite the 27% decrease of incidence in 1986 as compared to the previous year, the prevalence of a serogroup C strain that is associated with the highly virulent serotype 2a would indicate the need for careful surveillance of meningococcal disease in Italy.