Centrocestus formosanus (Trematoda: Heterophyidae) in Melanoides tuberculata (Gastropoda: Thiaridae) from Vila do Abraão, Ilha Grande, Rio de Janeiro, Brazil

Abstract

Pleurolophocercous cercariae found in the invasive gastropod Melanoides tuberculata (Müller, 1774) collected in a stream of the Vila do Abraão, Ilha Grande, Angra dos Reis, Rio de Janeiro, Brazil were used for experimental infection that enabled the identification of the heterophyid trematode Centrocestus formosanus (Nishigori, 1924). The parasite has been found in the locality since 2007, after two years of the introduction of M. tuberculata. Recently, from a sample of 483 specimens collected in June 2013, 101 (21%) were found infected with parasite. The potential environmental impacts caused by the parasite occurrence could be underestimated in the country, and actions to monitor and control both the parasite and the mollusk are necessary.Keywords: pleurolophocercous cercariae, invasion ecology, exotic freshwater snails. Centrocestus formosanus (Trematoda: Heterophyidae) emMelanoides tuberculata (Gastropoda, Thiaridae) da Vila do Abraão, Ilha Grande, Rio de Janeiro, Brasil ResumoCercárias do tipo pleurolofocerca encontradas no gastrópode invasor Melanoides tuberculata (Müller, 1774) coletados em um riacho da Vila do Abraão em Ilha Grande, Angra dos Reis, Rio de Janeiro, Brasil foram utilizadas em estudos de infecção experimental que possibilitaram a identificação do trematódeo heterofiídeo Centrocestus formosanus (Nishigori, 1924). O parasito vem sendo encontrado na localidade desde 2007, dois anos após a introdução do molusco. Recentemente, de uma amostra de 483 espécimes coletados em junho de 2013, 101 (21%) apresentavam-se infectados pelo parasito. Os potenciais impactos ambientais ocasionados pela ocorrência deste parasito podem estar sendo subestimados no país, sendo necessárias ações visando o monitoramento e controle tanto do parasito quanto do molusco.Palavras-chave: pleurolophocercous cercariae, ecologia da invasão, caramujos dulceaquícolas exóticos.

Diagnosis of Centrocestus formosanus Infection in Zebrafish (Danio rerio) in Italy: A Window to a New Globalization-Derived Invasive Microorganism

“…The occurrence of C. formosanus infection in zebrafish in Italy underlines the necessity to focus the attention on this invasive parasite, since this is the second case reported in the Italian peninsula [32]. Although its origin and distribution were initially restricted to Asia [4,[9][10][11][12][13]24,31], C. formosanus has been subsequently reported in other countries, including Europe [16][17][18][19][20][21][22]25,26,29,48]. Actually, to the authors' knowledge, this is the fourth case of C. formosanus infection in freshwater fish imported in Europe [19,32,40], confirming the introduction of this parasite in the European area, as well as the possible underestimation of this infection.…”

“…Within fish-borne trematodes, Centrocestus formosanus is a small heterophyid fluke, described for the first time in Taiwan [9] and widely distributed in Asia [4,5,[10][11][12][13][14][15]. Since the 1950s, several authors have reported this species in new continents, although its occurrence could still be underestimated [16][17][18][19][20][21][22]. C. formosanus, similar to other digenetic trematodes, exhibits a complex life cycle, as described by Nishigori [9].…”

“…Subsequently, free-swimming cercariae encyst in second intermediate fish hosts, specifically in the gills, where they develop into metacercariae. Piscivorous birds and mammals, ingesting the infected fish, complete the cycle [4,15,16,18,19,23]. Analogously, human infections can occur through consumption of raw or improperly cooked fish, containing metacercariae [12,15,24].…”

“…Analogously, human infections can occur through consumption of raw or improperly cooked fish, containing metacercariae [12,15,24]. C. formosanus is a generalist parasite with a broad range of fish hosts, in which it causes severe gill lesions, respiratory disorders, loss of production, and death, giving rise to health and economic concerns in relation to wild, farmed (food and ornamental), and laboratory fish [9,[17][18][19][25][26][27][28][29][30][31].…”

“…Given the importance of C. formosanus infection and dissemination for animal and public health, and the implications for aquaculture, research, and food safety, epidemiological investigations should be conducted in new geographical regions, in order to implement or improve appropriate preventive and control measures in these areas, as well as health-monitoring programs in research facilities [18,29,39].…”