Alveolar echinococcosis (AE) and cystic echinococcosis (CE) are severe helminthic zoonoses. Echinococcus multilocularis (causative agent of AE) is widely distributed in the northern hemisphere where it is typically maintained in a wild animal cycle including canids as definitive hosts and rodents as intermediate hosts. The species Echinococcus granulosus, Echinococcus ortleppi, Echinococcus canadensis and Echinococcus intermedius are the causative agents of CE with a worldwide distribution and a highly variable human disease burden in the different endemic areas depending upon human behavioural risk factors, the diversity and ecology of animal host assemblages and the genetic diversity within Echinococcus species which differ in their zoonotic potential and pathogenicity. Both AE and CE are regarded as neglected zoonoses, with a higher overall burden of disease for CE due to its global distribution and high regional prevalence, but a higher pathogenicity and case fatality rate for AE, especially in Asia. Over the past two decades, numerous studies have addressed the epidemiology and distribution of these Echinococcus species worldwide, resulting in better-defined boundaries of the endemic areas. This chapter presents the global distribution of Echinococcus species and human AE and CE in maps and summarizes the global data on host assemblages, transmission, prevalence in animal definitive hosts, incidence in people and molecular epidemiology.

Although fascioliasis has been relatively well studied, little is known about the molecular basis of this disease. This is particularly relevant, considering the very different response that sheep have to Fasciola hepatica relative to cattle. The acute phase of this disease is severe in sheep, whereas chronic fascioliasis is more common in cattle. To begin to explore the host-response to Fasciola in sheep and improve the understanding of the host-pathogen interactions during the parasite’s migration through liver parenchyma to the bile duct, we used RNA sequencing (RNA-seq) to investigate livers from sheep infected for eight weeks compared with those from uninfected controls. This study identified 572 and 42 genes that were up- and down-regulated, respectively, in infected livers relative to uninfected controls. Our molecular findings provide significant new insights into the mechanisms linked to metabolism, fibrosis and tissue-repair in sheep, and highlight the relative importance of specific components of immune response pathways, which appear to be driven toward a suppression of inflammation. This study is, to our knowledge, the first detailed investigation of the transcriptomic responses in the liver tissue of any host to F. hepatica infection. It defines the involvement of specific genes associated with the host’s metabolism, immune response and tissue repair/regeneration, and highlights an apparent overlapping function of many genes involved in these processes.

Purpose of Review Cystic and alveolar echinococcosis, caused by Echinococcus granulosus sensu lato and E. multilocularis, respectively, and Taenia solium cysticercosis are serious but neglected zoonotic diseases, caused by extra-intestinal cestode (tapeworm) infections. Humans are dead-end hosts for Echinococcus spp and acquire the infections by uptake of parasite eggs, either with contaminated food or via exposure by hand-mouth contact to eggs derived from the contaminated environment, including skin or coat of definitive hosts. Data related with the production of eggs of these parasites, their survival in the environment and the methodology for detection in food and environmental samples are summarized. Recent Findings The detection of taeniid DNA, more specifically from E. multilocularis, in food and soil has recently been described in some European countries. These findings have been directly connected with an increase in prevalence of human infections in countries like Poland. Summary The isolation and molecular identification of taeniid eggs is technically challenging and little standardized. The detection of taeniid DNA per se does not imply viability of eggs, and this must be considered when interpreting molecular results for transmission risk. Finally, easy, affordable, and sensitive methods replacing animal experiments should be developed to assess the viability of taeniid eggs isolated from environmental and food/water sources.