Prenatal screening for congenital toxoplasmosis in Campania: preliminary report on activities and results

By 1997, an open cohort of 1,652 live newborn of 1,637 mothers with gestational toxoplasmosis had been recruited in the Campania region to monitor the burden of congenital toxoplasmosis (CT). Of the 1,556 mother-child pairs that completed the follow up, 92 definite cases were detected, yielding a 5.9% (4.8-7.1 95% CI) transmission rate. The onset was patent for 43% of patients and sensorineural complications were shown for a further 15% of subclinical onset patients later than two years of age. The overall prevalence of toxoplasmosis during gestation was 2.46 of 1,000 deliveries, while the prevalence of definite CT was 1.38 of 10,000 live newborns. However, there is still room for intervention, as only 23% of the maternal diagnoses were proven through seroconversion, 63 of the late-gestation seroconverters remained untreated, and six probable CT diagnoses were made following referrals due to patent sequelae and born during the study period. There was a positive secular trend on the rates of infant referral and definite CT diagnosis, according to the live birth rate (Ç2 for trend < 0.001). Extension of this surveillance system across the country could help to define a future strategy for prevention.