Canine babesiosis (CB) is a significant tick-borne disease caused by intra-erytrocytic protozoa of the genus Babesia (Apicomplexa: Piroplasmida) and is currently emerging or re-emerging in many European countries. Despite the increasing incidence of clinical CB, little is known of the epidemiology of this disease in Romania. Therefore, the present study was conducted to provide epidemiological data on CB in the coastal area of the Black Sea (Dobrogea), southeastern Romania. For this, 306 owned dogs presented during 2016–2018 at a veterinary clinic in the area and clinically suspected for CB were tested for the presence of intra-erytrocytic piroplasms using Giemsa-stained thin blood smears. Overall, 27.8% (95% CI: 22.83–33.16) of dogs were positive for large piroplasms. The Babesia spp.–positive dogs were 51 males and 34 females aged from 3 mo to 13 yr (mean 4.2 yr; SD = 3.6). A higher rate of infection was registered in Bichon Maltese (n = 13) and mixed-breed (n = 28) dogs. Most cases (76/85; 89.4%) were diagnosed from March to June, with only a few cases registered in November and December (1 case each). Infected dogs displayed different clinical presentations, varying from mild (38.8%) to moderate (29.4%) and severe disease (29.4%). Based on clinical- pathological changes, 38 (44.7%), 34 (40.0%), and 13 (15.3%) dogs were diagnosed with uncomplicated babesiosis, complicated babesiosis with a single organ dysfunction, and complicated babesiosis with multiple-organ-dysfunction syndrome (MODS), respectively. The recovery rate (81.6%, 70.1%, and 38.4%, respectively) was significantly different in these groups. The age of dogs appeared to be a risk factor for both severe disease (mean age of 5.8 yr) and MODS (mean age 6.8 yr). These findings document the common occurrence of CB in Dobrogea, southeastern Romania, and suggest that appropriate control measures need to be taken.

Parasites can affect animal populations and communities in aquatic ecosystems. However, greater understanding is needed for the distributions and drivers of parasite infection levels in many areas. This study focuses on parasite prevalence (percent infected hosts) of an important class of parasites, trematodes, in 2 species of snail first intermediate hosts (Planorbella trivolvis and Physa sp.) in the Illinois River watershed, which has been impacted by human development. We hypothesized that trematode prevalence depends on local (e.g., water chemistry) and landscape (e.g., proximity to the Illinois River and land cover) factors. To test our hypotheses, we collected at least 20 individuals of 1 or both species of snails from 28 ponds within the watershed, and we made water-quality measurements and recorded habitat characteristics at each site. We then screened the snails for infections in the laboratory and identified the trematode cercariae that emerged based on morphological and molecular techniques. We found 5 cercariae morphotypes, including important parasites of wildlife, such as Echinostoma sp. and Ribeiroia ondatrae. Our results indicate that proximity to the Illinois River and open water or wetlands was positively associated with trematode prevalence in both snail species, whereas water chemistry (higher pH, lower calcium concentration, and lower specific conductance) was associated with increased prevalence, but only in Physa. Our findings offer increased understanding of potential environmental drivers underlying trematode distributions, with implications for wildlife health.

Eutrophication of aquatic habitats has become a global problem, with implications for host–parasite dynamics. Blooms of certain cyanobacteria are associated with cyanotoxins, particularly microcystins such as microcystin-LR (MC-LR). These potent toxins have been shown to adversely affect freshwater fauna and can increase host susceptibility to parasite infection. However, to understand how cyanotoxins influence infection outcomes in nature, it is necessary to investigate whether free-living parasite infectious stages, such as that of trematode cercariae, are also affected given their demonstrated sensitivity to various contaminants. Here we examined the effects of environmentally relevant levels of MC-LR representing relatively high (82 µg/L) and low (11 µg/L) concentrations on the activity and survival of four different types of cercariae (Echinostoma sp., Cephalogonimus sp., Alaria sp., and an unidentified strigeid type) over 24 hr. Exposure to MC-LR did not affect the activity of any cercarial type, nor was survival reduced. In fact, the strigeid-type cercariae had significantly increased longevity if exposed to either MC-LR solution, with the greatest longevity in the highest concentration. Our results indicate that MC-LR may have opposing effects on aquatic parasites and their hosts, potentially increasing host susceptibility but having a neutral or positive effect on motile infectious stages such as cercariae. Cyanobacterial blooms could thus enhance trematode transmission; however, the effects of other cyanotoxins must be studied, as well as a broader range of host and parasite species.

Studies on helminth communities associated with didelphids are scarce; the majority of works have focused at taxonomic level. To increase the ecological knowledge of these host–parasite associations, during March (dry season) of 3 consecutive years (2013–2015) a total of 49 adults of the gray four-eyed opossum (Philander opossum) was collected in the Neotropical portion of Mexico (Agua Fría, Chiapas State) and examined for helminths. The main objectives of this study were to describe the infra- and component communities of helminths associated with P. opossum and to compare the helminth fauna of the Mexican population of this host species with those studied in French Guiana and in other Mexican terrestrial didelphids. The helminthological record of this host consisted of 12 species: 7 taxa of Nematoda, 3 of Trematoda, 1 Cestoda, and 1 Acanthocephala. Eight of the 12 taxa have been previously recorded in Didelphidae and 4 represent accidental infections (Glossocercus sp., Stomylotrema vicarium, Spirura mexicana and Acanthocephala gen. sp.). Diet of hosts is the main structuring factor of the communities (92% of the helminth species were recruited through ingestion). Forty-eight hosts were parasitized by at least 1 helminth species; Rhopalias coronatus was the most prevalent and abundant species in the hosts sampled. No significant differences were found in global prevalence among the helminth species present in all samplings, considering host sex and year. The dominance exerted by R. coronatus led to low values of evenness and diversity at both community levels. No significant differences were observed in composition of helminth species among the 3 sampling years regarding sex. The results of our study showed changes in helminth abundance at infracommunity level; during the first sampling these changes are explained by species with direct life cycle (Viannaia sp. and Cruzia tentaculata), whereas in last 2 surveys the explanation can be attributed to species with heteroxenous life cycles (particularly R. coronatus, Duboisiella proloba, and Turgida turgida). Thirty-three percent of the helminth species recorded in P. opossum in Agua Fría is shared with the other 2 terrestrial species of didelphids sampled in different sites of Mexico: Didelphis marsupialis and Didelphis virginiana. In contrast, samples from French Guiana and Agua Fría, differ in terms of helminth fauna, confirming that the helminth communities of opossum species inhabiting the same locality show higher levels of taxonomic similarity than communities of conspecific marsupials allopatrically distributed.

The goal of parasite epidemiologists is to understand the factors that determine host infection levels. Potential infection determinants exist at many scales, including spatial and temporal environmental variation, among-host differences, and interactions between symbionts infecting the same host. All of these factors can impact levels of parasitism, but frequently only a subset is considered in any host-parasite system. We examined several potential determinants of pinworm infection in wild Australian cockroaches (Periplaneta australasiae) from multiple biological scales: (1) habitat; (2) season; (3) cockroach body size, developmental stage, and sex; and (4) interactions between 2 pinworm species (Leidynema appendiculata and Thelastoma sp.). Over 1 yr, we collected 239 cockroaches from 2 separate rooms in an Illinois greenhouse. We used generalized linear mixed-effects models (GLMMs) to evaluate simultaneously the influence of these factors on pinworm abundance, and nearly all had significant effects. Overall, the abundance of L. appendiculata was greater than Thelastoma sp., but the relative abundance of the 2 species was reversed in each room (i.e., a taxon × habitat effect). Abundance varied over 4 trapping seasons and increased with cockroach size. Adult cockroaches had more pinworms than nymphs, and there was also a significant taxon × stage effect: adult cockroaches had fewer pinworms than expected for their larger size, and this reduction was greater in Thelastoma sp. than in L. appendiculata. Cockroach sex had no effect on infection. Although females had more worms than males, this difference could be explained by the larger size of females. Finally, after controlling for all other potential determinants of infection, we found a strong negative association between Thelastoma sp. and L. appendiculata; cockroaches tended to be infected with either 1 pinworm species or the other. Our work underscores the importance of measuring potential determinants of infection from as many scales as possible. Such approaches are necessary to unravel the complexities of host-parasite interactions.

Dispersal influences the evolution and adaptation of organisms, but it can be difficult to detect. Host-specific parasites provide information about the dispersal of their hosts and may be valuable for examining host dispersal that does not result in gene flow or that has low signals of gene flow. We examined the population connectivity of the buffy flower bat, Erophylla sezekorni (Chiroptera: Phyllostomidae), and its associated obligate ectoparasite, Trichobius frequens (Diptera: Streblidae), across a narrow oceanic channel in The Bahamas that has previously been implicated as a barrier to dispersal in bats. Due to the horizontal transmission of T. frequens, we were able to test the hypothesis that bats are dispersing across this channel, but this dispersal does not result in gene flow, occurs rarely, or started occurring recently. We developed novel microsatellite markers for the family Streblidae in combination with previously developed markers for bats to genotype individuals from 4 islands in The Bahamas. We provide evidence for a single population of the host, E. sezekorni, but 2 populations of its bat flies, potentially indicating a recent reduction of gene flow in E. sezekorni, rare dispersal, or infrequent transportation of bat flies with their hosts. Despite high population differentiation in bat flies indicated by microsatellites, mitochondrial DNA shows no polymorphism, suggesting that bacterial reproductive parasites may be contributing to mitochondrial DNA sweeps. Parasites, including bat flies, provide independent information about their hosts and can be used to test hypotheses of host dispersal that may be difficult to assess using host genetics alone.

Trichostrongylid nematodes are a common cause of gastroenteritis in sheep. Despite its worldwide distribution, Teladorsagia circumcincta has not been included in reports listing the various trichostrongyles infecting sheep from Egypt. Herein, we describe the presence of 2 T. circumcincta haplotypes infecting small ruminants from Egypt. For this study, fresh fecal samples were collected from 340 sheep and 115 goats reared at 5 districts in Dakahlia governorate and its surroundings, Egypt. Trichostrongyle eggs were harvested from the samples, and then subjected to DNA isolation and analysis. Polymerase chain reaction (PCR) amplification was carried out for the second internal transcribed spacer of ribosomal DNA (ITS2 rDNA). Purified PCR products of T. circumcincta were sequenced, and the revealed sequences were subjected to the nucleotide and phylogenetic analysis. A relatively high prevalence of trichostrongyles eggs was identified in sheep (33.2%) and a lower prevalence was found in goats (14.7%). Molecular analysis revealed, for the first time, 2 sheep herds from Egypt that were infected with T. circumcincta. Both infected herds were raised by the Bedouins in rural areas of El Mahalla El Kubra city. No T. circumcincta infections were found in any of the goats. Nucleotide sequence analysis revealed 2 haplotypes (Te1 and Te2) from 7 successfully sequenced samples (5 from the first and 2 from the second herd). Te1 was the major haplotype in both herds, and Te2 was retrieved from a single sample. Phylogenetic analysis displayed that the Te1 haplotype clustered with one from Cyprus, which might have been introduced to Egypt via goats imported from Cyprus due to a program to improve meat and milk production in Egypt. The present results could be beneficial in understanding the epidemiology of T. circumcincta and other trichostrongyles in Egypt, and have implementations in the effective control strategies used in this region.

Learedius learediPrice, 1934, is a blood fluke found in sea turtles, and the adult fluke parasitizes the cardiovascular system of the host. In this study we surveyed 46 green sea turtles, Chelonia mydas, on the Ogasawara Islands, Japan, and blood flukes were detected in the heart and blood vessels of 26 turtles. The flukes were identified as L. learedi based on a detailed morphological description. In addition, molecular identification and characterization of the parasite were performed. The nucleotide sequences of nuclear internal transcribed spacer 2 (ITS2) regions were almost identical to those of L. learedi reported previously, but not to those of Hapalotrema spp., which is the closest related genus. The nucleotide sequences of the 28S ribosomal DNA region formed a single clade with those of the reference L. learedi in the phylogenetic tree, but not with those of Hapalotrema spp. Therefore, the nucleotide sequences of ITS2 and 28S are robust markers for distinguishing L. learedi from other species. The nucleotide sequences of the mitochondrial cytochrome c oxidase subunit 1 (COI) region were analyzed to evaluate the genetic variations in L. learedi. The COI haplotypes revealed the extremely high genetic diversity of the species as well as the host turtles on the Ogasawara Islands. The haplotype frequency in the mitochondrial DNA of the green sea turtles on the Ogasawara Islands is known to be significantly different from those in other Pacific rookeries. Although the number of analyzed flukes is small in this study, no haplotype was close to that in other areas; on the basis of the data, we hypothesized that L. learedi differentiated along with the host turtles on the Ogasawara Islands.

Given a changing climate and large-scale human migration, understanding infectious diseases in wildlife and the factors that drive the spread of these diseases is becoming increasingly important. Owing to the close phylogenetic relationship between nonhuman primates and humans, primate parasites are of particular interest due to the potential for zoonotic disease transmission and for the study of social transmission within gregarious social groups. There is a wide range of social and environmental factors that influence the prevalence and transmission of pathogens, and identifying these, and their effects, is crucial to understanding the population-level consequences of climate change for animals that live in obligate social groups. Here we investigated gastrointestinal parasite species richness and used fecal egg counts to estimate worm intensities in 3 vervet monkey troops (Chlorocebus pygerythrus) in a high latitude, semi-arid region of South Africa. This region is characterized by unpredictable rainfall and temperature extremes in summer and winter. We identified the gastrointestinal parasites in the population and explored potential demographic predictors, namely sex and troop membership, of parasite species richness and estimated intensity. Additionally, we assessed whether there was short-term intra-individual, inter-sample consistency in egg counts. Six species of gastrointestinal helminths were identified from 3 study troops, with egg counts ranging from 0 eggs/g to 1,100 eggs/g. Neither age nor sex predicted species richness or estimated intensity. This population had the highest prevalence of parasites with an insect vector compared with all other vervet populations studied, and distinctively high prevalences of Trichostrongylus sp. (71%) and Ternidens sp. (27%). Additionally, we found intra-individual egg count consistency in the short term (mean: 32 days).

Infection with the cat-borne parasite Toxoplasma gondii has been detected in numerous Australian marsupials and can lead to severe disease (toxoplasmosis) in some cases. The seroprevalence of Toxoplasma on Kangaroo Island, South Australia has been reported to be higher than the South Australian mainland in macropods, cats, and sheep, suggesting an increased risk of infection on this island. However, Toxoplasma seroprevalence in small- and medium-sized terrestrial mammals was almost zero on the island and did not differ from that on the mainland. We surveyed Toxoplasma seroprevalence in koala (Phascolarctos cinereus) populations on the island and on the mainland and assessed their risk of infection and their role in the life cycle of Toxoplasma. All screened koalas from the island (n = 94) and the mainland (n = 63) were seronegative. This represents the largest Toxoplasma seroprevalence survey in this species and provided sufficient evidence to confidently demonstrate freedom from parasite exposure in both island and mainland populations at the time of the survey. Because koalas are extensively arboreal and predominately consume tree foliage, they appear to be at negligible risk of Toxoplasma infection. Furthermore, as koalas are rarely consumed by cats, we suggest that they have a minor role in the parasite's life cycle.

Piroplasmosis is a disease of domestic and wild animals caused by tick-borne protozoa of the genera Theileria and Babesia. Piroplasmosis leads to substantial economic losses in the livestock industry. This disease has been frequently reported in subtropical and tropical regions worldwide. However, information regarding the prevalence of piroplasma in ticks collected from dogs and cattle is lacking in most areas. To assess the potential threat of piroplasmosis in South China, 671 ticks were collected in Guangxi Province. Deoxyribonucleic acid (DNA) was extracted from these ticks to evaluate the presence of piroplasma through a reverse line blot (RLB) hybridization assay using the hypervariable V4 region of the piroplasmic 18S ribosomal ribonucleic acid (r)RNA genes as probes to detect Theileria and Babesia species. The RLB results indicated that 144/671 (21.46%) ticks were infected with piroplasma species belonging to the genera Theileria or Babesia. Theileria buffeli, Babesia vogeli, Theileria annulata, and Theileria luwenshuni were present in the ticks at frequencies of 60/671 (8.94%), 21/671 (3.13%), 6/671 (0.89%), and 6/671 (0.89%), respectively. Mixed infections with 2 or more piroplasma species were present in 8/671 (1.19%) tick samples. The hypervariable V4 region of the piroplasmic 18S rRNA genes from 6 tick DNA samples with single infections was cloned, sequenced, and aligned to related sequences from GenBank. The Theileria and Babesia sequences were analyzed separately. 18S rRNA gene fragment sequences of T. annulata and T. buffeli were compared with previously reported homologous sequences. All 3 B. vogeli sequences examined in this study were grouped into the same cluster and belonged to the same genotype. The present study provides important epidemiological information regarding piroplasmosis occurrence in China. The existence of tick-borne piroplasma likely leads to high infection risks among the local animals in the studied areas.

Taenia solium is a helminth parasite that causes 2 diseases in humans: cysticercosis and taeniasis. The establishment of T. solium metacestodes in the central nervous system causes neurocysticercosis, while development of the adult tapeworm in the small intestine causes taeniasis. Serological diagnosis of neurocysticercosis is performed by Western blot with an enriched fraction of glycoproteins that has been extensively used for clinical diagnosis and epidemiological surveys. The lectin-bound fraction that is used for this assay contains 7 antigenic glycoproteins. These antigenic proteins are considered to be highly specific for cysticercosis when tested with heterologous parasitic diseases. However, recent studies show that people with taeniasis have cross-reactive antibodies against the neurocysticercosis diagnostic glycoproteins and vice versa. Nevertheless, it is not known if these diagnostic proteins are expressed in the adult stage of the parasite. In this paper, we describe the location of 3 of these glycoproteins in T. solium adults and cysticerci using polyclonal antibodies raised against a synthetic peptide based on the amino acid sequence of TS14, a recombinant protein T24H, and the native GP50. The glycoproteins' distribution was different in invaginated and evaginated cysticerci as well as in adult tapeworms. Specifically, the 3 glycoproteins studied were differentially expressed during embryogenesis. Our findings indicate that expression of the diagnostic glycoproteins is developmentally regulated; this is noteworthy since these glycoproteins are considered specific for the diagnosis of neurocysticercosis but nevertheless are present in different structures throughout the development of T. solium. Here we describe the glycoprotein expression and localization, which can be important in understanding their biological functions. In addition, our results help clarify the cross-reaction observed between people with neurocysticercosis and taeniasis to TS14, T24H, and GP50, which are used as diagnostic antigens for neurocysticercosis.

Equine piroplasmosis caused by Theileria equi and Babesia caballi is an economically important disease with a worldwide distribution. The objective of the present study was to investigate the seroepidemiology of T. equi and B. caballi in horses reared in various Mongolian provinces. Serum samples prepared from blood collected from horses in 19 Mongolian provinces were screened for antibodies specific to T. equi and B. caballi using enzyme-linked immunosorbent assays based on recombinant forms of T. equi merozoite antigen-2 and the B. caballi 48-kDa merozoite rhoptry protein, respectively. Of 1,282 horses analyzed, 423 (33%) and 182 (14.2%) were sero-positive for T. equi and B. caballi, respectively. Additionally, 518 (40.4%) were positive for at least 1 parasite species, of which 87 (16.8%) were co-infected with both parasites. Both T. equi and B. caballi were detected in all surveyed provinces, and on a per province basis the positive rates ranged from 19.0 to 74.2% and 4.5 to 39.8%, respectively. Theileria equi- and B. caballi-positive rates were comparable between male horses (31.9 and 14.1%, respectively) and female horses (34.5 and 14.3%, respectively). However, the positive rates were higher in the >3-yr-old age group (37.7 and 15.6%, respectively) compared with the 1–3-yr-old age group (19.4 and 10.0%, respectively). These findings confirmed that T. equi and B. caballi infections are widespread among horses all over Mongolia, and that horse age is a risk factor for infection in this country. Our results will be useful for designing appropriate control measures to minimize T. equi and B. caballi infections among Mongolian horses.

Two new genera and species of freshwater turtle blood flukes (TBFs) are described herein based on specimens infecting the nephritic and mesenteric blood vessels of “matamatas” (a side-necked turtle, Chelus fimbriata [Schneider, 1783] [Pleurodira: Chelidae]) from the Amazon River Basin, Peru. These taxa comprise the first-named species and the first-proposed genera of freshwater TBFs from the continent of South America. A new comparison of all TBF genera produced 6 morphologically diagnosed groups that are discussed in light of previous TBF classification schemes and a novel phylogenetic hypothesis based on the nuclear large subunit ribosomal DNA (28S). Considering external and internal anatomical features, species of the new genera (Atamatam Bullard and Roberts n. gen., Paratamatam Bullard and Roberts n. gen.) are most similar to each other and are together most similar to those of several marine TBF genera. The 28S phylogenetic analysis supported the monophyly of all 6 morphologically diagnosed groups of genera. Most notably, the freshwater TBFs of South America comprise a derived group nested within the clade that includes the paraphyletic marine TBFs. Not surprisingly in light of morphology, another marine TBF lineage (Neospirorchis Price, 1934) clustered with the freshwater TBFs of Baracktrema Roberts, Platt, and Bullard, 2016 and Unicaecum Stunkard, 1925. Our results, including an ancestral state reconstruction, indicated that (1) freshwater TBFs have colonized marine turtles twice independently and that (2) the South American freshwater TBFs comprise a marine-derived lineage. This is the first evidence that TBFs have twice independently transitioned from a marine to freshwater definitive host. Marine incursion is considered as a possible mechanism affecting the natural history of marine-derived freshwater TBFs in South America. A dichotomous key to accepted TBF genera is provided.

A new species of nematode, Ascarophis morronei n. sp. (Cystidicolidae), is described from the stomach wall of the woolly sculpin Clinocottus analis (Cottidae) collected in the rocky intertidal from northwestern Baja California, Mexico. Collected nematodes were studied using both light and scanning electron microscopy. Sequence fragments for 18S rDNA molecular markers were obtained from the new nematode species, in order to test its position within the family Cystidicolidae under a phylogenetic context. Main characters distinguishing this new species include the reduced labia and the morphology of the eggs, distances of nerve ring and excretory pore from the anterior end, and left spicule of males. The new species described here is the second for the genus Ascarophis reported as adult in the Southern California Bight, and the first one recorded for the fish genus Clinocottus.

A new species of medicinal leech, Macrobdella mimicus n. sp., is described from specimens collected in Maryland; this is the first description of a North American macrobdellid since 1975. Superficially, the new species resembles the well-known Macrobdella decora, as both species possess 4 accessory pores arranged symmetrically on the ventral surface, yet the new species is distinguished from M. decora in possessing 4–4½ annuli (rather than 3½) between the gonopores and 4 annuli (rather than 5 annuli) between the female gonopore and the first pair of accessory pores. Phylogenetic analyses, based on 2 mitochondrial and 2 nuclear loci for a set of closely related taxa, confirms the placement of the new species within the family Macrobdellidae and places it as the sister taxon to M. decora and M. diplotertia.

Specimens of 3 species of Neoechinorhynchus Stiles and Hassall, 1905, were collected from a number of species of marine fish along the Pacific coast of Vietnam. New information is added to the descriptions of Neoechinorhynchus (Neoechinorhynchus) longnucleatusAmin, Ha, and Ha, 2011, and its wider host and geographical distribution are reported. Similarly, more descriptive information and host and geographical records are added to our knowledge of Neoechinorhynchus (Hebosoma) manubrianusAmin, Ha, and Ha, 2011, and Neoechinorhynchus (Neoechinorhynchus) dimorphospinusAmin and Sey, 1996. The latter species was previously known only from the Persian Gulf. The presence of the para-receptacle structure was documented in all 3 species of Neoechinorhynchus reported. The molecular characterization of N. dimorphospinus was carried out using a partial 18S rDNA sequence. The phylogenetic analysis showed that most species of Neoechinorhynchus are very closely related, while N. dimorphospinus was distinct from others in the tree. Metal analysis of hooks of N. dimorphospinus using Energy Dispersive X-ray Analysis also distinguished its characteristic finger print of high phosphorus and calcium and low sulfur levels.

Although parasitic infection by Trichuris trichiura is a very common intestinal helminthic disease worldwide, there is still insufficient information on the genetic characteristics of ancient T. trichiura in different spatiotemporal perspectives. Utilizing coprolite specimens obtained from 15th–18th century mummies dating to the Joseon Dynasty, we analyzed small-subunit ribosomal RNA, internal transcribed spacer 2, and ATP synthase subunit 8 of T. trichiura ancient DNA (aDNA). In BLAST and phylogenetic analyses, the T. trichiura aDNA sequences of this study belong to a separate cluster that is evidently distinct from the other genus Trichuris spp. reported in GenBank. This report characterizes T. trichiura aDNA of pre-20th century East Asia, and in so doing, it also proves the potential of aDNA analysis for differential diagnosis of T. trichiura in cases where ancient parasite eggs are morphologically indeterminate for species identification.

We describe the thin and ultra-thin structures of the envelopes surrounding the cystacanth of Corynosoma strumosum (Rudolphi, 1802) Lühe, 1904, in its intermediate host. A total of 4,357 amphipods from 2 species were examined: Locustogammarus locustoides (Brandt, 1851) and Spinulogammarus ochotensis (Brandt, 1851). Eleven corynosome cystacanths were found in 6 S. ochotensis specimens. Three were enclosed in acellular cysts originating from the parasite. Three other cystacanths were also encysted and were surrounded by a lighter capsule consisting of the host's hemocytes. Five cystacanths were enclosed in a cyst and a darker capsule, in which both the acanthocephalans and their surrounding envelopes were destroyed. We suggest that the cystacanth's cyst is a protective barrier against the host's cellular response, while the lighter and darker capsules represent different stages of parasite degeneration.

Introduction of ticks into the United States that can carry disease-causing pathogens to humans, companion animals, and wildlife has accelerated in recent years, mostly due to globalization, frequency of travel, and a rise in legal and illegal animal trades. We hereby report for the first time introduction of a live fully engorged Amblyomma coelebs feeding on a human into the United States from Central America. Amblyomma coelebs is geographically distributed in the Neotropical region and reaches the southern states of Mexico. This species is capable of transmitting a number of pathogens of public health and veterinary importance including spotted fever group rickettsiae, raising concern that A. coelebs, if it became established in the United States, might also be able to carry these pathogens. Considering the risks of exotic ticks as vectors of numerous pathogens and their potential to establish new populations under conducive climatic and habitat conditions, rigorous inspection practices of imported livestock and pet animals at ports of entry are vital. It is also important for travelers and practitioners to develop a heightened awareness of the public health risks associated with the unintended importation of exotic ticks and the potential such parasites have for breaching United States biosecurity defenses.

Albino strains of Biomphalaria glabrata that are compatible with Schistosoma mansoni are commonly used to investigate snail-schistosome interactions, but whether they are all equally compatible is not known. In this study, compatibility with the Naval Medical Research Institute (NMRI) strain of S. mansoni was compared among 3 widely used albino strains: NMRI (the normal laboratory host for NMRI S. mansoni), M line, and University of Massachusetts Lowell (UML). Compatibility was assessed on the basis of infection prevalence following exposure to miracidia, the histological fate of sporocysts, and mitotic response in the snail amebocyte-producing organ (APO), a component of the internal defense system (IDS). Infection prevalence in UML was nearly identical to that in NMRI but was significantly lower in M line. Although the APO of UML showed no response to infection over the course of 9 days, mitotic activity was elevated in the APO of NMRI and M line, with that in M line being higher and more prolonged than in the APO of resistant BS-90 snails. Finally, hemocyte responses against some small primary sporocysts occurred at 1 and 3 days post-exposure (DPE) in all 3 strains, but in 2 of 5 M line a response also occurred against large primary sporocysts at 6 DPE. Thus, based on infection prevalence and tissue responses, compatibility with NMRI S. mansoni is lowest in M line, whereas UML and NMRI show the same degree of compatibility, despite decades of maintenance of this parasite strain in NMRI snails. The elevated mitotic response in the APO of M line and NMRI snails suggests that a response of the IDS can occur even in a compatible host-parasite relationship.

Philophthalmid eyeflukes are cosmopolitan parasites of birds and occasionally of mammals, including humans. A gravid adult of Philophthalmus sp. was found from the bulbar conjunctiva of a 64-yr-old woman in Japan, who was diagnosed with acute conjunctivitis. The parasite was morphologically most similar to Philophthalmus hegeneri, but distinctive in lacking an esophagus and in having clearly lobed testes. The DNA sequence analysis of genes for nuclear 28S ribosomal RNA and mitochondrial cytochrome c oxidase subunit 1 supported the identification at generic level. The morphological and molecular analyses strongly suggest that the eyefluke from a human in Japan should be treated as an undescribed species of Philophthalmus. The occurrence of human philophthalmosis is very rare. As far as we know, a total of 11 human cases have been reported worldwide to date.