Untreated acute
toxoplasmosis among
pregnant women can
lead to serious sequelae among
newborns, including neurological impairment and
blindness. In
Brazil, the
risk of
congenital toxoplasmosis (CTox) has not been fully evaluated. Our aim was to evaluate
trends in acute
toxoplasmosis prevalence from 1998-2005, the
incidence of CTox and the rate of
mother-to-child transmission (MTCT). A
cross-sectional study was undertaken to dentify
patients who fit the criteria for acute
toxoplasmosis during
pregnancy. Exposed
newborns were included in a historical cohort, with a median follow-up
time of 11 months, to establish definite
diagnosis of CTox.
Diagnoses for acute
infection in
pregnancy and CTox were based on European
Research Network on
Congenital Toxoplasmosis criteria. In 41,112
pregnant women, the
prevalence of acute
toxoplasmosis was 4.8/1,000
women. The
birth prevalence of CTox was 0.6/1,000
newborns [95 percent
confidence interval (CI) 0.4-0.9]. During the
follow-up study, 12 additional cases were detected, increasing the CTox rate to 0.9/1,000
newborns (95 percent CI 0.6-1.3). Among the 200
newborns exposed to
Toxoplasma gondii,there were 37 babies presenting diagnostic criteria of CTox, leading to an MTCT rate of 18.5 percent (95 percent CI 13.4-24.6 percent). The additional cases identified during follow-up reinforce the need for serological
monitoring during the first year of
life, even in the absence of evidence of
congenital infection at
birth.