[Evaluation of prevention strategies for congenital toxoplasmosis: a critical review of medico-economic studies]

Congenital toxoplasmosis (CT) may lead to serious neurological or sensory consequences. A serological screening of women at risk of acquiring toxoplasmosis became mandatory in France, first during the visit before wedding (1978), then during the visit for pregnancy declaration (1985) and at last with a monthly follow-up during pregnancy since 1992. The efficacy and the profitability of the program was never assessed, in spite of the modification of the epidemiological context. However medico-economical studies were conducted in countries in which no prevention program for CT was available to determine the interest of an antenatal screening similar to the French one or of other prevention strategies.Eight studies comparing at least two strategies were selected. Methodologies used in those studies were analyzed by two independent readers with the help of a standardized scale. A score was calculated for each study.Each study analyzed suffered from methodological limitations, in particular concerning the estimation of antenatal treatment efficacy, which could lead to invalidate their conclusion. The most reliable studies in regard to methodological guidelines, that is with the higher score, concluded that antenatal screening was not contributive. However, they could not be transposed directly in the present French situation, because of the difference of the epidemiological and economical context.Given the difficulty to obtain a clear conclusion, it seems necessary to perform a rigorous decision analysis to identify the more effective and acceptable program in terms of human and financial costs for preventing congenital toxoplasmosis.