This issue of the Journal of Helminthology includes a special topic dealing with six reviews on various aspects of parasitic helminths in Latin America and the Caribbean (LAC). The majority refer to helminths infecting aquatic hosts and range from fundamental questions to epidemiology and control challenges.

Helminth infections are highly prevalent over large areas of LAC, where they cause severe morbidity and seriously affect the efficiency of food production systems. As in other regions of the world, they are a hallmark of poverty and, furthermore, a major hindrance to development (Hotez et al., Reference Hotez, Bottazzi, Franco-Paredes, Ault and Periago2008a, Reference Hotez, Brindley, Bethony, King, Pearce and Jacobsonb; Budke et al., Reference Budke, White and García2009). In this scenario, parasitologists from LAC countries have been working for more than a century, together with colleagues from all over the world, to contribute to a better understanding of the biology of these organisms and the diseases they cause, and to develop new tools for their diagnosis, treatment and control (see, for example, Mascarini, Reference Mascarini2003; Verjovski-Almeida et al., Reference Verjovski-Almeida, DeMarco, Martins, Guimaraes, Ojopi, Paquola, Piazza, Nishiyama, Kitajima, Adamson, Ashton, Bonaldo, Coulson, Dillon, Farias, Gregorio, Ho, Leite, Malaquias, Marques, Miyasato, Nascimento, Ohlweiler, Reis, Ribeiro, Sa, Stukart, Soares, Gargioni, Kawano, Rodrigues, Madeira, Wilson, Menck, Setubal, Leite and Dias-Neto2003; Díaz et al., Reference Díaz, Casaravilla, Irigoin, Lin, Previato and Ferreira2011a, Reference Díaz, Casaravilla, Allen, Sim and Ferreirab; Gazzinelli et al., Reference Gazzinelli, Correa-Oliveira, Yang, Boatin and Kloos2012; Parkinson et al., Reference Parkinson, Wasmuth, Salinas, Bizarro, Sanford, Berriman, Ferreira, Zaha, Blaxter, Maizels and Fernández2012; Silva et al., Reference Silva, Marcet-Houben, Nahum, Zerlotini, Gabaldon and Oliveira2012; Matoso et al., Reference Matoso, Oliveira-Prado, Abreu, Fujiwara, Loverde, Kloos, Gazzinelli and Correa-Oliveira2013; Morel et al., Reference Morel, Lassabe, Elola, Bondad, Herrera, Mari, Last, Jensen and González-Sapienza2013; Sciutto et al., Reference Sciutto, Fragoso, Hernandez, Rosas, Martinez, Fleury, Cervantes, Aluja and Larralde2013; Tsai et al., Reference Tsai, Zarowiecki, Holroyd, Garciarrubio, Sanchez-Flores, Brooks, Tracey, Bobes, Fragoso, Sciutto, Aslett, Beasley, Bennett, Cai, Camicia, Clark, Cucher, De Silva, Day, Deplazes, Estrada, Fernandez, Holland, Hou, Hu, Huckvale, Hung, Kamenetzky, Keane, Kiss, Koziol, Lambert, Liu, Luo, Luo, Macchiaroli, Nichol, Paps, Parkinson, Pouchkina-Stantcheva, Riddiford, Rosenzvit, Salinas, Wasmuth, Zamanian, Zheng, Cai, Soberon, Olson, Laclette, Brehm and Berriman2013; Williams et al., Reference Williams, Bonilla, Gladyshev and Salinas2013; Cooper et al., Reference Cooper, Chico, Platts-Mills, Rodrigues, Strachan and Barreto2015; Oliveira & Pierce, Reference Oliveira and Pierce2015; García et al., Reference García, Gonzalez, Tsang, O'Neal, Llanos-Zavalaga, Gonzalvez, Romero, Rodriguez, Moyano, Ayvar, Diaz, Hightower, Craig, Lightowlers, Gauci, Leontsini and Gilman2016; Koziol et al., Reference Koziol, Jarero, Olson and Brehm2016; Peón et al., Reference Peón, Ledesma-Soto and Terrazas2016; McNulty et al., Reference McNulty, Tort, Rinaldi, Fischer, Rosa, Smircich, Fontenla, Choi, Tyagi, Hallsworth-Pepin, Mann, Kammili, Latham, Dell'Oca, Dominguez, Carmona, Fischer, Brindley and Mitreva2017).

Along these lines is the article on fasciolosis by Fasciola hepatica in South America. José Tort and Carlos Carmona (Universidad de la República, Uruguay) review the epidemiology of helminth infection in livestock and other hosts, and efforts to develop a single-antigen recombinant vaccine for ruminants. They also examine the important issue of drug resistance, which is compromising current control strategies worldwide. The review by Lilia Soler-Jiménez et al. (Centro de Investigación y Estudios Avanzados, CINVESTAV, Mexico) also concerns parasites affecting food production, notably finfish. The authors highlight that, while aquaculture has tripled over the past 20 years in Latin America, it is currently facing the problem of helminth infections. Noting that aquaculture mainly uses exotic species, and that parasites were brought into the region together with their hosts, they raise the point that the introduction of species for production purposes should be considered a breakdown in biosecurity, and be treated as such.

Two reviews analyse helminth diversity in different hosts. Leopoldina Aguirre-Macedo and colleagues (CINVESTAV, Mexico) review patterns of diversity in helminths infecting aquatic invertebrates in LAC. Given the availability of data, they focus on parasites affecting medically and economically important hosts (mainly snails, shrimps and crabs). Similarly, José Luis Luque (Universidade Federal Rural do Rio de Janeiro, Brazil) and colleagues analyse the diversity of helminth parasites from South American fishes. Both these articles emphasize the need of further studies to assess properly helminth diversity in the region.

The final two reviews focus on questions related to ecology and evolution. Victor Vidal-Martínez (CINVESTAV, Mexico) and Alison Wunderlich (University of London, UK) carried out a meta-analysis seeking evidence of a response of parasitic helminths to environmental damage and, therefore, whether helminths may be used as bioindicators of damage in the region. Interestingly, they found a low but significant indication of such a response and observed differences among parasite groups. Finally, Anindo Choudhury (St Norbert College, USA) together with Martín García-Varela and Gerardo Pérez-Ponce de León (CINVESTAV, Mexico) examined the extent to which adult helminths from freshwater fishes have been part of the Great American Biotic Interchange, finding that helminth interchange has been limited and asymmetrical.

Together, these reviews show that, in the LAC, helminthology is a thriving subject, with research directed at both important applied problems of the region and fundamental aspects of helminth ecology and evolution.