[Estimation of the epidemiological impact of various BCG vaccination scenarios in France].
BACKGROUND
Within the current process of revising the vaccination policy against tuberculosis in France, we have estimated the epidemiological impact of three future possible options for BCG primo-vaccination: continuation of routine vaccination of all children, targeting on high risk children or discontinuation.


METHODS
We have used tuberculosis mandatory notification data to estimate the number of cases currently prevented each year through BCG vaccination, corresponding to the excess incidence, in case of discontinuation of the vaccination. The proportion of cases occurring in high risk children has been estimated through data from a study carried out in 1997 in the Paris region. The contribution of high risk children to the French child population has been estimated using data from INSEE and INED.


RESULTS
In the most favorable scenario for vaccination, up to 800 additional cases would have occurred annually, considering all BCG vaccination activities in children were interrupted. The selective vaccination strategy would induce around 200 additional cases each year considering the coverage remained at its current level. Therefore the vaccination of less than 15% of each annual birth cohort would allow prevention of around three quarters of the cases currently occurring.


CONCLUSIONS
BCG vaccination of high risk children seems to be an efficient strategy. However, its current effectiveness would depend on the capacity to maintain a high vaccination coverage in this population in the context of the abrogation of mandatory vaccination and the impending disappearance of BCG administered by multipuncture, which is the technique used in France for the vast majority of primo-vaccinations. Beyond the economical and epidemiological parameters, the decision will have to consider the operational, social and ethical issues raised by a vaccination strategy targeting children mainly of foreign origin.
Lévy-Bruhl
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Département des maladies infectieuses-Institut de Veille Sanitaire, 12, rue du Val d'Osne, 94415 Saint-Maurice Cedex. d.levybruhl@invs.sante.fr
D001500:BCG Vaccine; D002648:Child; D015331:Cohort Studies; D004526:Efficiency; D005602:France; D006291:Health Policy; D006801:Humans; D015994:Incidence; D019221:Mandatory Reporting; D010297:Paris; D012307:Risk Factors; D014397:Tuberculosis, Pulmonary / Q000453:epidemiology* / Q000517:prevention & control; D014611:Vaccination / Q000706:statistics & numerical data
D001500:BCG Vaccine