Work

Zoonotic Centrocestus formosanus (Digenea: Heterophyidae) infecting Melanoides tuberculata (Mollusca: Thiaridae) in Ecuador. Genetic characterization

Year: 2026

Type: article

Abstract: ABSTRACT We report the first molecularly confirmed record of the zoonotic heterophyid trematode Centrocestus formosanus infecting the invasive freshwater snail Melanoides tuberculata in tropical coastal Ecuador. A total of 902 M . tuberculata was examined, and cercarial shedding was induced under laboratory conditions. Two snails (0.22%) released cercariae morphologically consistent with Heterophyidae, and subsequent PCR amplification and sequencing of the ITS2 region confirmed C. formosanus . Phylogenetic analysis using the maximum-likelihood method (GTR model, 500 bootstrap replicates) revealed high genetic similarity to reference sequences from Egypt, Vietnam, Japan, and Denmark. Our findings contribute to the knowledge of expanding of this medically important zoonotic parasite in South America and identifying M. tuberculata as a competent intermediate host in the region. Given the role of C. formosanus in fish pathology and its capacity to infect humans through the consumption of raw or undercooked freshwater fish, this record raises concerns regarding potential public health and aquaculture impacts. Further studies are warranted to assess infection prevalence, identify local fish and definitive hosts, and evaluate the zoonotic risk in Ecuadorians.

Source: International Journal for Parasitology Parasites and Wildlife

DOI: 10.1016/j.ijppaw.2026.101228

Authors: Carlos Bastidas-Caldes, Fernanda Hernández-Alomia, Juan Pablo Negrete, Manuel Calvopina

Institutions: Universidad Espíritu Santo, Instituto Nacional de Biodiversidad, Universidad de Las Américas

Language: English

Topic: Parasite Biology and Host Interactions

Subfield: Ecology

Field: Environmental Science

Domain: Physical Sciences

SDG: Good health and well-being

Open Access status: gold

Estimated APC paid: $1,930