The successful use of helminths as therapeutic agents to resolve inflammatory disease was first recorded 40 years ago. Subsequent work in animal models and in humans has demonstrated that the organisms might effectively treat a wide range of inflammatory diseases, including allergies, autoimmune disorders and inflammation-associated neuropsychiatric disorders. However, available information regarding the therapeutic uses and effects of helminths in humans is limited. This study probes the practices and experiences of individuals ‘self-treating’ with helminths through the eyes of their physicians. Five physicians monitoring more than 700 self-treating patients were interviewed. The results strongly support previous indications that helminth therapy can effectively treat a wide range of allergies, autoimmune conditions and neuropsychiatric disorders, such as major depression and anxiety disorders. Approximately 57% of the self-treating patients observed by physicians in the study had autism. Physicians reported that the majority of patients with autism and inflammation-associated co-morbidities responded favourably to therapy with either of the two most popular organisms currently used by self-treaters, Hymenolepis diminuta and Trichuris suis. However, approximately 1% of paediatric patients experienced severe gastrointestinal pains with the use of H. diminuta, although the symptoms were resolved with an anti-helminthic drug. Further, exposure to helminths apparently did not affect the impaired comprehension of social situations that is the hallmark of autism. These observations point toward potential starting points for clinical trials, and provide further support for the importance of such trials and for concerted efforts aimed at probing the potential of helminths, and perhaps other biologicals, for therapeutic use.

The current study was conducted to evaluate the nature of association of ABO blood type with helminth infection and related reduction in haemoglobin concentration. Stool samples were collected from 403 school-age children attending Tikur Wuha Elementary School from February to April 2011. Helminth infection was examined using formol-ether concentration and thick Kato–Katz (two slides per stool specimen) techniques. Haemoglobin level was determined using a HemoCue machine and ABO blood type was determined using the antisera haemagglutination test. Nutritional status was assessed using height and weight measurements. Out of 403 children examined, 169, 120, 96 and 18 had blood type O, A, B and AB, respectively. The prevalences of helminth infections were 46.9% for hookworm, 24.6% for Schistosoma mansoni, 4.2% for Ascaris lumbricoides, 1.7% for Trichuris trichiura and 58.3% for any helminth species. The relative odds of infection with at least one helminth species was significantly higher among children with blood type A (adjusted odds ratio (AOR), 2.10; 95% confidence interval (CI), 1.28–3.45) or blood type B (AOR, 2.08; 95% CI, 1.22–3.56) as compared to children with blood type O. Among children infected with helminths, mean haemoglobin concentration was lower in those with blood type A than those with blood type O (β, −0.36; 95% CI, −0.72 to −0.01). The relative odds of hookworm infection (AOR, 1.78; 95% CI, 1.08–2.92) and related reduction in haemogobin levels (β, −0.45; 95% CI, −0.84 to −0.04) was higher among children with blood type A as compared to those with blood type O. Although the difference was not significant, the relative odds of S. mansoni or A. lumbricoides infections and related reduction in haemoglobin levels was also higher in children with blood type A or B as compared to children with blood type O. In conclusion, children with blood type A are associated with an increased risk of helminth, particularly hookworm, infection and related reduction in haemoglobin level. The mechanisms by which blood type A makes children susceptible to helminth infection and a related reduction in haemoglobin level ought to be investigated.

Temperature is a key factor influencing the rate of biological processes of ectothermic animals and is intrinsically linked to climate change. Trematode parasites may be potentially susceptible to temperature changes and, in order to develop a predictive framework of their response to climate change, large-scale analyses are needed. In particular, the biology of the egg of all species is at some time influenced by environmental conditions. The present study uses Arrhenius activation energy (E*), a common measure of temperature-mediated reaction rates, to analyse experimental data from the scientific literature on the effects of temperature on the production, development and hatching of trematode eggs. Egg production declines at high temperatures, with habitat-specific climatic factors determining the optimal thermal range. Egg development, as is typical of invertebrates, shows a simple response to temperature, with minimal differences between mid- (35–60°) and low-latitude (<35°) species. Egg hatching demonstrates variable thermodynamics with high E* values at low temperature ranges and thermostability at mid-temperatures, before declining at high temperature ranges, with wide thermostable zones being a common feature. Comparisons between development and hatching indicate that these two parameters demonstrate different thermodynamical responses. The significance of these results in furthering our understanding of trematode egg biology under natural conditions is discussed.

Knowledge of trematode infections in Biomphalaria pfeifferi from south-eastern Nigeria is scarce, due to the absence of Schistosoma mansoni infection in the region. Therefore, the present study sought to describe trematode infections in B. pfeifferi from the River Uzuru in the Nigeria Cement Factory area, Nkalagu, south-eastern Nigeria. Four hundred and sixty snails were checked for trematode infections, and mice were exposed to the Schistosoma cercariae shed from the snails. Adult worms were harvested from the mice 13 weeks post-infection, while sections of the liver and spleen were examined. Primary school children living in the area were screened for S. mansoni infection and assessed for activities involving water contact. The edges of the river were also searched for burrows and rodents. The five cercaria morphotypes found were armatae xiphidiocercariae, echinocercariae, Schistosoma cercariae, cystophorous cercariae and cercariaeum cercariae. The overall prevalence and mean intensity of trematode infections were 39.78% and 195.46, with the prevalence and mean intensity of most cercaria morphotypes higher in the hot–dry than in the cool–dry season. The infected mice showed S. mansoni-like characteristics but the stool samples of the schoolchildren were negative for S. mansoni eggs. Water-contact activities in the River Uzuru were minimal. Burrows were seen at the river edges but no Schistosoma eggs were recovered from captured rats. This is the first report of Schistosoma cercariae and other cercaria morphotypes in B. pfeifferi from south-eastern Nigeria. Additional molecular investigations are needed to identify correctly these Schistosoma cercariae, due to their public health implication.

The aim of this paper was to evaluate the genetic relationship between two isolates of Opisthorchis (O. pedicellata sp. 1, O. pedicellata sp. 2) from two siluroid fish hosts, based on three nuclear DNA (18S, internal transcribed spacer 1 (ITS1) and ITS2). Molecular analysis revealed that both isolates of 18S sequences showed low intraspecific variability (1.6%), while this was 1.9% for ITS1 and 2.6% for ITS2. The secondary structure of the ITS2 region exhibited a remarkable four-helix model, with helices 1 and 4 being relatively short, three U–U mismatches in helix 2 and the longest helix (3) having two UGGG motifs. The phylogenetic analyses, using neighbour–joining (NJ) and maximum parsimony (MP) methods of MEGA 6, demonstrate that both isolates form a sister clade with significant support (100%). Therefore, we concluded that both the isolates of O. pedicellata are of the same species but some variations may be due to the sympatric environment of variant hosts.

Ecological characteristics and environmental variation influence both host species composition and parasite abundance. Abiotic factors such as rainfall and temperature can improve parasite development and increase its reproduction rate. The comparison of these assemblages between different environments may give us a more refined analysis of how environment affects the variation of helminth parasite abundance. The aim of the present study was to evaluate how temporal variation, host size, sex and reproduction affect helminth abundance in the Tropidurus hispidus lizard in Caatinga, Restinga and Atlantic Forest environments. Overall, larger-sized lizards showed higher helminth abundance. We found a monthly variation in the helminth species abundance in all studied areas. In the Caatinga area, monoxenic and heteroxenic parasites were related to the rainy season and to the reproductive period of lizards. In Restinga, monoxenic and heteroxenic helminth species were more abundant during the driest months. In the Atlantic Forest, the rainy and host reproductive season occurred continuously throughout the year, so parasite abundance was relatively constant. Nevertheless, heteroxenic species were more abundant in this area. The present results showed that the temporal variation, body size, sex, reproductive period and habitat type influence the abundance and composition of helminth species in T. hispidus.

Trichinella species are zoonotic nematodes that infect wild carnivores and omnivores throughout the world. We examined the prevalence and species of Trichinella infections in cougars (Puma concolor couguar) from Colorado, United States. Tongues from cougars were examined by pepsin–HCl artificial digestion to detect Trichinella spp. larvae. The species or genotype of individual worms was identified by multiplex polymerase chain reaction (PCR). Trichinella spp. larvae were detected in 17 of 39 cougars (43.6% (28.7–59.5%)). Five of the cougars (12.8%) were infected with T. murrelli, 3 (7.7%) were infected with T. pseudospiralis, and 1 (2.6%) had Trichinella genotype T6. Trichinella spp. larvae from eight cougars were not identified at the species level, due to degraded DNA. The high prevalence of Trichinella spp. in cougars from Colorado and reports of the parasite in other populations of Puma spp. suggest that this large predator is a key mammalian reservoir.

Adult Lecithaster mugilis Yamaguti, 1970 were found in Moolgarda seheli, Valamugil engeli and Liza subviridis in the coastal waters of Cat Ba Island (Halong Bay, Vietnam). Specimens of Lecithaster sudzuhensis n. sp. were found in Mugil cephalus located in an estuary of the Kievka River in the Primorsky region of Russia. Studies have demonstrated that these species share significant morphometric similarities with each other and with specimens of L. helodes Overstreet, 1973 isolated from M. cephalus and Mugil curema from the Mississippi Sound and adjacent waters. These three species differ from one another in the size of the pharynx and ventral sucker and in the ratio of suckers, while they differ from other species in the genus by having a relatively elongated oesophagus. Molecular analysis, using the 18S rRNA and 28S rRNA genes, confirmed the validity of L. mugilis and L. sudzuhensis n. sp. and demonstrated that these species form a shared cluster with L. gibbosus (Rud, 1802).

Among eyeflukes, Tylodelphys Diesing, 1850 includes diverse species able to infect the eyes, but also the brain, pericardial sac and body cavity of their second intermediate host. While the genus shows a cosmopolitan distribution with 29 nominal species in Africa, Asia, Europe and America, a likely lower research effort has produced two records only for all of Australasia. This study provides the first description of a species of Tylodelphys and the first record for a member of the Diplostomidae in New Zealand. Tylodephys sp. metacercaria from the eyes of Gobiomorphus cotidianus McDowall, 1975 is distinguished from its congeners as being larger in all, or nearly all, metrics than Tylodelphys clavata (von Nordmann, 1832), T. conifera (Mehlis, 1846) and T. scheuringi (Hughes, 1929); whereas T. podicipina Kozicka & Niewiadomska, 1960 is larger in body size, ventral sucker and holdfast sizes and T. ophthalmi (Pandey, 1970) has comparatively a very small pharynx and body spination. Tylodelphys sp. exhibits consistent genetic variation for the 28S rDNA, internal transcribed spacer (ITS) and Cox1 genes, and phylogenetic analyses confirm that it represents an independent lineage, closely related to North American species. Morphological and molecular results together support the distinct species status of Tylodephys sp. metacercaria, the formal description and naming of which await discovery of the adult. Furthermore, the validity of T. strigicola Odening, 1962 is restored, T. cerebralis Chakrabarti, 1968 is proposed as major synonym of T. ophthalmi, and species described solely on the basis of metacercariae are considered incertae sedis, except those for which molecular data already exist.

Adults of Lasiotocus lizae Liu, 2002 (Monorchiidae) were found in the mullet Liza longimanus (Günther) from Tonkin Bay, near Cat Ba Island, Vietnam. In this region, flukes belonging to the genus Paucivitellosus (Bivesiculudae) were found in Liza subviridis (Valenciennes), Liza engeli (Bleeker) and Valamugil seheli (Forskåi). Results of investigations showed that morphological features of L. lizae (like L. glebulentus Overstreet, 1971) do not meet the criteria of the genus Lasiotocus. In addition, L. lizae is highly differentiated from other species of Lasiotocus from which molecular data were obtained, including L. arrhichostoma Searle, Cutmore et Cribb, 2014 and L. typicum (Nicoll, 1912). Phylogenetic analyses revealed that L. lizae differs considerably from other species of the genus Lasiotocus presented in the GenBank database. We have identified a new species of the genus Paucivitellosus–P. vietnamensis sp. n. – from L. subviridis, which differs from P. fragilis Coil, Reid et Kuntz, 1965 by metrical and molecular (18S rRNA) data, and from P. hanumanthai Mani, 1989 by metric features. Our results also show considerable molecular differentiation between P. vietnamensis sp. n. and Paucivitellosus spp. recovered from L. engeli and V. seheli in Vietnam.

There is little information on the phylogenetic position and life cycle of family Kathlaniidae. Falcaustra araxiana is a member of this family which infects the large intestine of the European pond turtle (Emys orbicularis). In the present study, morphological data and molecular analyses based on the 18S rDNA were performed on different types of F. araxiana originating from the large intestine and gastric nodules in the turtle. Morphological data revealed both larvae and adult stages in the gastric nodules. In addition, all nematodes recovered in the large intestine were adult worms. GenBank accession numbers KM200715 and KM200716 were provided for adult F. araxiana located in the intestine and stomach, respectively, of E. orbicularis. The results of sequencing proved that these two types are completely similar. Accordingly, it can be hypothesized that nodule formation is a part of the life cycle of the parasite or a survival strategy. Furthermore, F. araxiana develops to the adult stage in the gastric mucosa prior to migrating to the large intestine. Phylogenetic analysis revealed that F. araxiana unexpectedly branched away from other members of the superfamily Seuratoidea (Truttaedacnitis truttae, Cucullanus robustus and C. baylisi) and showed a closer relationship with Paraquimperia africana, a member of the Ascaridoidea. It seems that phylogenetic reconstruction for the present parasite needs more detailed morphology, life cycle and molecular studies.

Serpentirhabdias viperidicus n. sp. (Nematoda: Rhabdiasidae) is described from the lungs of the ‘Brazilian lancehead’ Bothrops moojeni (Hoge, 1966) from the savannah in São Paulo State, Brazil. The new species is the eighth species of Serpentirhabdias described in the Neotropical region, and differs from other species mainly by a combination of characters: lips slightly notable, presence of fine striations at posterior ends, presence of two parallel lines with intercalated pores, a pore-shaped phasmid situated at the level of the anal aperture and another two in the posterior half of the tail. It is the first species of Serpentirhabdias reported in this snake host and the second species of this genus found parasitizing South American viperidian snakes. Molecular phylogenetic analysis using ribosomal (ITS and 28S partial) genes confirms Serpentirhabdias viperidicus n. sp. as a new species that clustered in the Serpentirhabdias clade, sister taxon to Serpentirhabdias fuscovenosa and Serpentirhabdias elaphe. This is the first description of Serpentirhabdias species from Brazil using molecular approaches and morphological characters to confirm the monophyly of this recent genus.

Thorny-headed acanthocephalan worms of the genus Profilicollis are widely distributed in the oceans of the world and present complex life cycles with intermediate and definitive hosts. The genus is still poorly known, with an unstable taxonomy and, for most species, incompletely characterized geographical distributions. In this study, based on molecular and morphological evidence, we report that the species Profilicollis altmani is also distributed along the South American Atlantic coast, using the mole crab Emerita brasiliensis as an intermediate host. As such, our record shows that P. altmani has a Pan-American distribution where five species of Emerita are utilized as intermediate hosts.

Although the efficacy of triclabendazole treatment against Fasciola gigantica has been shown before in cattle and buffaloes, there appears to be no published report on the efficacy of triclabendazole in impala or other antelope species. As part of a health monitoring programme at Mulungushi International Conference Centre, Lusaka, Zambia, a coprological examination was undertaken to investigate the helminthological status of captive impala (Aepyceros melampus). Of 39 fresh coprological samples, 46% contained F. gigantica. The source of infection was identified to be a fountain within the grounds of the conference centre. Lymnaea natalensis, collected from the study site, were induced to shed cercariae, and were thus confirmed as the snail intermediate host. In managing this disease, triclabendazole at 6 mg/kg was administered together with the feed bait. Water from the pond was drained; vegetation within it cleared and the pond allowed to dry for 1 week before water was replaced. Three weeks post-treatment, faecal examination revealed that the Fasciola had been cleared. To the best of our knowledge, this is a first case of Fasciola spp. infection reported in captive wild impala in Zambia and provides evidence that triclabendazole may be delivered to free-ranging antelope using medicated bait.

Canine echinococcosis is caused by the adult tapeworm of Echinococcus granulosus. As intermediate hosts, humans and livestock become infected following ingestion of eggs that are passed in the faeces of dogs. Mature eggs develop into hydatid cysts in different organs, leading to hydatid disease, which is a serious public health problem. In the present study, we investigated the proportion of mature eggs of E. granulosus in 140 dogs from three regions of Tunisia. The results showed the predominance of immature E. granulosus eggs in infected dogs and the occurrence of a small proportion of oncospheres. The ability of immature eggs to infect humans and livestock is discussed.

Kalicephalus is a genus of strongylid nematodes infecting snakes and causing serious diseases and even death when it is complicated with secondary bacterial infections. The infection of snakes with Kalicephalus has been reported in many countries in the world. However, little information is available on the prevalence of Kalicephalus in snakes in China. In the present study, the prevalence of Kalicephalus in snakes was investigated. The worms were examined, counted and identified to species according to existing keys and descriptions. Three species of Kalicephalus, namely K. indicus, K. bungari and K. brachycephalus, were found in six species of snakes (Elaphe carinata, Zaocys dhumnade, Naja najaatra, Elaphe taeniura, Bungarus multicinctus and Dinodon rufozonatum). The total prevalence of Kalicephalus in snakes in Hunan Province was 39.7%. The most common species was K. indicus, with the highest prevalence 72.8%, followed by K. bungari (24.0%). The prevalence of K. brachycephalus was 0.9%. This is the first report on the prevalence of Kalicephalus species in snakes in China, and the findings have important implications for the control of Kalicephalus infections in snakes in China.