Many snail species act as intermediate hosts of helminths that transmit diseases
to humans and animals, such as schistosomiasis and angiostrongyliasis. São
Gonçalo, a mostly urban municipality in Rio de Janeiro State, Brazil, has
undergone fundamental environmental impacts, which favor the establishment of a
range of diseases, for which snails act as the intermediate hosts of the
etiological agents. In the present study, freshwater and terrestrial snail
populations were surveyed in different environments within five city districts,
and the presence of helminths was determined in the collected specimens. A total
of 287 individuals were collected, six species from freshwater environment,
Pomacea sp. (Ampullariidae), Melanoides
tuberculata (Thiaridae), Biomphalaria tenagophila
(Planorbidae), Dysopeas muibum (Subulinidae), Physa
marmorata, and Physa acuta (Physidae), and two
from terrestrial environment, Achatina fulica (Achatinidae) and
Bradybaena similaris (Bradybaenidae). Snails were found in
only two districts, Centro, an urban area, and Ipiiba, a rural area. Thirteen
percent of the specimens of A. fulica eliminated larvae of the
nematode Angiostrongylus cantonensis. None of the analyzed
freshwater snails contained helminths.The most abundant and frequent snails were
B. tenagophila, M. tuberculataand
A. fulica, and the latter two species are exotic. The
disturbance and degradation of natural areas adjacent to residential zones favor
the proliferation of helminths, jeopardizing the local residents health. The
abundance of A. fulica and B. tenagophila in
the study area reinforces the need for a continuous and systematic monitoring of
the snail fauna in this region.