[The return of diphtheria in Europe. Is the French population protected?]

Following the generalized vaccination of children, the European countries achieved the elimination of diphtheria. However the huge epidemic which rages since 1990 in the New Independent States of ex-URSS, culminating in 1994-1995 (with respectively 47,802 and 50,412 notified cases), has showed that diphtheria could be still threatening. A serosurvey was carried out in France on 1,025 adult patients attending the emergency wards of three hospitals, located in different parts of this country. This study showed the insufficient immunity of adults, for lack of a routine programme for revaccination: only half of them have antibodies assuring their protection. The antitoxic immunity decreases according to age. This decline is more marked in women than in men, most of them being reimmunized during the military service. These data confirm the alarming results of similar serosurveys performed in others industrialized countries. The present risk of importing diphtheria in these countries requires a strengthening of clinical and bacteriological surveillance of all cases of infections attributable to C. diphtheriae, and could justify a revaccination programme for adult population, including a regular booster, at 10 year-interval, of a reduced dose of diphtheria toxoid (d), and/or using the combined toxoid Td in the wounded, instead of tetanus toxoid alone.