Human-induced growth of macro-algae is often assumed to increase trematode infections in fishes by increasing the abundance and condition of the parasite’s intermediate host – snails – as this can boost the release of trematode larvae, cercariae, from the intermediate hosts. However, macro-algae can also impose barriers to the transmission of cercariae and reduce infections. We investigated whe...

Franz cells (2-chambered, air/fluid phase static diffusion devices, previously used for the study of drugs across viable human skin) are utilized for the first time to investigate the process of infection of human skin by Schistosoma mansoni cercariae. Skin obtained from cosmetic surgery sources was used in the Franz cells to describe the temporal dynamics of the early interaction of cercariae ...

In the production of the infective cercariae of trematodes, the terminal investment hypothesis of life-history theory predicts that the rate of host exploitation and cercarial production should increase during the period of cercarial shedding since the reproductive value of the parasite decreases during this period. In contrast, a bet hedging hypothesis that focuses on the success of transmissi...

Digenean trematodes are common and abundant in aquatic habitats and their free-living larvae, the cercariae, have recently been recognized as important components of ecosystems in terms of comprising a significant proportion of biomass and in having a potentially strong influence on food web dynamics. One strategy to enhance their transmission success is to produce high numbers of cercariae whi...

A study on trematode obtained from freshwater snails in 30 grow-out giant gourami ponds supplied by well water was conducted Chau Thanh district, Tien Giang province, Vietnam. The were sampled the flooding season (October 2020), intermediary (January 2021) and non-flooding (April 2021). Eight snail species belonging to 8 genera, 4 families found including Sermyla tornatella (48.6%), Sinotaia li...

Schistosoma japonicum is a widespread human and animal parasite that causes intestinal and hepatosplenic schistosomiasis linked to colon, liver and bladder cancers, and anemia. Estimated 230 million people are currently infected with Schistosoma spp, with 779 million people at risk of contracting the parasite. Infection occurs when a host comes into contact with cercariae, a planktonic larval s...

Keratinocytes constitute the majority of cells in the skin's epidermis, the first line of defence against percutaneous pathogens. Schistosome larvae (cercariae) actively penetrate the epidermis to establish infection, however the response of keratinocytes to invading cercariae has not been investigated. Here we address the hypothesis that cercariae activate epidermal keratinocytes to promote th...

The present investigation involves a reevaluation of previous results obtained after experimental infection of Swiss Webster mice with cercariae and schistosomula of the Schistosoma mansoni LE strain maintained under laboratory conditions. Three experimental groups of mice were considered: the animals of the first group were percutaneously (ring method) infected with cercariae, those of the sec...

Infectivity of Pseudechinoparyphium echinatum cercariae to 11 species of gastropod was examined experimentally. Broad specificity and differential host-parasite compatibility were exhibited. Nine gastropod species functioned as second intermediate hosts. Planorbarius corneus, Physa fontinalis, Lymnaea peregra and Biomphalaria alexandrina showed high levels of compatibility with the parasite. In...

Two new Stephanostomum-like cercariae, Cercaria capricornia VII and Cercaria capricornia VIII (Digenea: Acanthocolpidae), are described from the nassariid gastropods Nassarius dorsatus and Nassarius olivaceus collected from the intertidal zone in the Capricornia region of Central Queensland, Australia. Morphological analysis of these new cercariae was augmented with DNA sequence data from the l...