Severe schistosomiasis is a rare event in Venezuela nowadays,
after a successful national campaign by the Schistosomiasis Control Program.
Unfortunately, this program has practically disappeared, and snail surveillance
in field is not a priority, anymore. Thus, schistosomiasis has become a
neglected disease in this country. However, surveys in different populations
from the endemic area have shown particular epidemiological features described
herein. In five communities we evaluated 2,175 persons and searched for
the presence of
Biomphalaria glabrata
snails. Some markers were used for classifying schistosomiasis foci: mean
age of the persons with
Schistosoma mansoni
eggs in the stools, serological tests, presence of
B. glabrata
snails, and intensity of infection. Places without
B. glabrata
snails and with few schistosomiasis cases were defined as "past transmission
sites"; a site with abundant snails but few cases was defined as "potential
risk"; "new transmission" foci were characterized by the presence of
infected snails and young people passing eggs in the stools. A "re-emergent"
focus has shared these last features, showing in addition a place where
schistosomiasis had been reported before. Recent evidences of active transmission
with the increasing dispersion of
B. glabrata
snails, point out the necessity for the re-establishment of the Schistosomiasis
Control Program in Venezuela.
