New treatment strategies for schistosomiasis should be evaluated, since resistant strains to the only available drug, Praziquantel, have already been described. Thus, we demonstrated antiparasitic effects of ethanolic extracts of Jatropha gossypiifolia and Piper arboreum on cercariae and adult worms of Schistosoma mansoni. The bioassays were performed at 0–10 000 μg mL−1 concentration for 0–72 h. Adult worms were stained with carmine to assess external and internal damage. The chemical screening was performed using high-performance liquid chromatography. P. arboreum displayed the best cercaricidal effect, with a 100% reduction in viability in just 60 min. The extract of J. gossypiifolia was more effective against adult worms, with 100% viability reduction of male and female worms after 12 and 24 h, respectively. P. arboreum and J. gossypiifolia were equally effective in inhibiting the oviposition of S. mansoni (93% reduction) and causing damage to internal and external structures in adult worms. Flavonoids were identified in both the extracts and phenolic compounds and amides only in P. arboreum. Thus, for the first time, it was proven that ethanolic extracts of P. arboreum and J. gossypiifolia leaves are biologically active against cercariae and adult worms of S. mansoni in vitro.

Toxoplasmosis is a parasitic zoonotic disease caused by Toxoplasma (T.) gondii. Limited data are available on the occurrence of T. gondii in women especially pregnant women in Pakistan. The present study aimed to determine the occurrence and risk factors associated with T. gondii in pregnant and non-pregnant women in Punjab Province, Pakistan. A cross-sectional study was conducted and 593 samples were collected from pregnant (n = 293) and non-pregnant (n = 300) women of District Headquarter Hospitals of Chiniot, Faisalabad, Jhang and Okara, Pakistan. Data related to demographic parameters and risk factors were collected using a pretested questionnaire on blood sampling day. Serum samples were screened for antibodies (IgG) against T. gondii using ELISA. A univariant and binomial logistic regression was applied to estimate the association between seropositive and explanatory variables considering the 95% confidence interval. P value ⩽0.05 was considered statistically significant for all analysis. Out of 593, 44 (7.42%) women were seropositive for T. gondii IgG antibodies. Occupation, age, sampling location, socioeconomic status, contact with cat, pregnancy status and trimester of pregnancy were significantly associated with seropositivity for T. gondii antibodies. Location and trimester of pregnancy were identified as potential risk factors for T. gondii seropositivity based on binomial logistic regression. Toxoplasma gondii is prevalent in pregnant and non-pregnant women. Therefore, now a necessitated awareness is required to instruct the individuals about these infectious diseases (toxoplasmosis) and their control strategies to maintain the health of human population. Moreover, health awareness among public can help the minimization of T. gondii infection during pregnancy and subsequent risk of congenital toxoplasmosis.

Despite the great interest to quantify the structure of host–parasite interaction networks, the real influence of some factors such as taxonomy, host body size and ecological opportunity remains poorly understood. In this paper, we investigate the general patterns of organization and structure of interactions in two anuran–parasite networks in the Brazilian Pantanal (seasonally flooded environment) and Atlantic Forest (non-flooded forest). We present theoretical models to test whether the structures of these host–parasite interaction networks are influenced by neutrality, host taxonomy and host body size. Subsequently, we calculated metrics of connectance, nestedness and modularity to characterize the network structure. We demonstrated the structure networks were influenced mainly by body size and taxonomy of the host. Moreover, our results showed that the seasonally flooded environment present networks with higher connectance/nestedness and lower modularity compared to the other environment. The results also suggest that seasonal floods may promote ecological opportunities for new species associations.

Pregnancy is considered a period in which immunomodulation occurs, although it is important for the maintenance of the foetus, could contribute to infections as Toxoplasma gondii. Immune response cells such as regulatory T cells participate in this immunomodulation, and surface molecules such as CTLA-4 develop an immunosuppressive role, could contribute to the establishment of the parasite. This study aimed to evaluate the presence of regulatory T cells and the expression of CTLA-4 in parturient and non-pregnant seropositive and seronegative for anti-T. gondii antibodies. Sixty-two participants were evaluated, 14 parturient with negative serology, 23 parturient with positive serology, 16 non-pregnant women seronegative and 9 non-pregnant women seropositive. Immunophenotyping was performed for characterize TCD4+Foxp3+ cells, T CD4+CD25-Foxp3+, TCD4+CD25highFoxp3+, TCD4+CTLA-4+, TCD4+CD25-CTLA-4+ and TCD4+CD25highCTLA-4+. We observed a lower level of CD4+CD25highFoxp3+ cells from seropositive parturient compared with seropositive non-pregnant cells. Significative levels of CD4+CD25-Foxp3+ cells from seronegative pregnant were observed compared with seropositive pregnant cells. Furthermore, the higher level of CD4+CD25-CTLA-4+ cells populations was detected in seropositive pregnant cells compared with seropositive non-pregnant. Although a significant increase in CTLA-4 cells was observed in pregnant women positive for anti-T. gondii antibodies, this increase did not cause a risk of reactivation of the infection.

Avian malaria (caused by Plasmodium spp.) and avian malaria-like infections (caused by Haemoproteus spp.) are widespread and can seriously affect the health of their bird hosts, especially of immunologically naïve individuals. Therefore, these parasites have long been in the focus of bird-parasite studies. However, the species richness and diversity of these protozoan species have only been revealed since the use of molecular techniques. Diversity and prevalence of these parasites among different bird species and even between populations of a species show a large variation. Here, we investigated prevalence of avian malaria and avian malaria-like parasites in two distant populations of a non-migratory wetland specialist passerine, the bearded reedling (Panurus biarmicus). While previous studies have shown that reed-dwelling bird species often carry various blood parasite lineages and the presence of the vectors transmitting Plasmodium and Haemoproteus species has been confirmed from our study sites, prevalence of these parasites was extremely low in our populations. This may either suggest that bearded reedlings may avoid or quickly clear these infections, or these parasites cause high mortality in this species. The remarkably low prevalence of infection in this species is consistent with earlier studies and makes bearded reedlings a possible model organism for investigating the genetic or behavioural adaptations of parasite resistance.

Cochliomyia hominivorax larvae cause myiasis in animals and humans. To register a commercial product to control this dipteran is necessary to experiment on animals. The in vitro test was standardized to evaluate the larvicidal efficacy of commercial topical products. Five formulations were analysed in vitro and in vivo. For the in vitro test, a colony was formed and three replicates (n = 200) of each larval stage (L1, L2 and L3) were treated. The viability of the larvae was evaluated after 5 and 30 min, and at 1, 2, 6, 12, 24, 48, 60 and 72 h post-treatment (HPT). For the in vivo test, 30 bovines divided into six groups were castrated to achieve natural infestation with C. hominivorax. Animals in the treated groups received the product. Myiasis and efficacy were evaluated 12, 24, 36, 48, 60 and 72 HPT. Four formulations tested in the in vitro test achieved 100% efficacy at 24 HPT. In the in vivo experiment only one achieved 100% efficacy at 24 HPT. However, all products achieved the maximum efficacy by the end of study. The in vitro test developed here could be adopted to evaluate the efficacy of topical products for the control of C. hominivorax larvae.

Due to the efforts to control schistosomiasis transmission in tropical countries, a large proportion of individuals from endemic areas present low parasite loads, which hinders diagnosis of intestinal schistosomiasis by the Kato-Katz (KK) method. Therefore, the development of more sensitive diagnostic methods is essential for efficient control measures. The aim was to evaluate the accuracy of a real-time polymerase chain reaction (RT-PCR) to detect Schistosoma mansoni DNA in fecal samples of individuals with low parasite loads. A cross-sectional population-based study was conducted in a rural community (n = 257) in Brazil. POC-CCA® was performed in urine and feces were used for RT-PCR. In addition, fecal exams were completed by 18 KK slides, saline gradient and Helmintex techniques. The combined results of the three parasitological tests detected schistosome eggs in 118 participants (45.9%) and composed the consolidated reference standard (CRS). By RT-PCR, 117 out of 215 tested samples were positive, showing 91.4% sensitivity, 80.2% specificity and good concordance with the CRS (kappa = 0.71). RT-PCR identified 86.9% of the individuals eliminating less than 12 eggs/g of feces, demonstrating much better performance than POC-CCA® (50.8%). Our results showed that RT-PCR is a valuable alternative for the diagnosis of intestinal schistosomiasis in individuals with very low parasite loads.

Cattle production in extensive systems favours the occurrence of gastrointestinal nematodes, and the use of nematophagous fungi complements the control strategies for these nematodes. The aim of this study was to evaluate the effectiveness of the fungi Arthrobotrys cladodes and Pochonia chlamydosporia in the biological control of gastrointestinal parasitic nematodes in grazing cattle. Twenty-four calves were randomly divided into four groups and allocated to independent paddocks from February 2018 to January 2019. In the first group, the animals received pellets containing P. chlamydosporia. In the second group, the animals received pellets containing A. cladodes. In the third group, the animals received pellets containing a combination of the fungi A. cladodes and P. chlamydosporia. In the control group, the animals received pellets without fungus. The combined use of A. cladodes and P. chlamydosporia showed greater efficacy in the biological control of bovine gastrointestinal parasitic nematodes than the same fungi used separately. The parasite load was lower and weight gain was greater (P ⩽ 0.05) in the groups of cattle treated with nematophagous fungi. Therefore, the use of A. cladodes and P. chlamydosporia is promising in the biological control of nematodiosis in cattle.

Gyrodactylid parasites were observed on non-native populations of North-American freshwater catfishes, Ameiurus nebulosus and Ameiurus melas (Siluriformes: Ictaluridae), at several sites in the Elbe River basin, Czech Republic, Europe. Using a combination of morphological and genetic analyses, the parasites infecting A. nebulosus were determined to be Gyrodactylus nebulosus, a North American parasite co-introduced to Europe along with its Ameiurus fish hosts. Subtle morphometrical differences, as well as seasonal variations, were observed among parasites collected from A. nebulosus and A. melas. The host-related variation was further supported through genetic analysis of the partial 18S rDNA, ITS1-5.8S-ITS2 and COI, showing 0.2, 3.0 and 4.8% divergence, respectively. Consistent genetic differences indicated there were two distinct genotypes. Subtle morphological differences associated with the shape of sickle toe, anchor root and ventral bar membrane, according to host species, also supported the description of a new cryptic species, Gyrodactylus melas n. sp., infecting A. melas. Multivariate morphometrical analysis of haptoral hard parts showed significant differences between the anchor lengths of G. nebulosus and G. melas n. sp. However, the measurements of the haptoral hard structures partially overlapped between species, limiting the usage of these parameters for species delineation.

Costa Rica is near malaria elimination. This achievement has followed shifts in malaria health policy. Here, we evaluate the impacts that different health policies have had on malaria transmission in Costa Rica from 1913 to 2018. We identified regime shifts and used regression models to measure the impact of different health policies on malaria transmission in Costa Rica using annual case records. We found that vector control and prophylactic treatments were associated with a 50% malaria case reduction in 1929–1931 compared with 1913–1928. DDT introduction in 1946 was associated with an increase in annual malaria case reduction from 7.6% (1942–1946) to 26.4% (1947–1952). The 2006 introduction of 7-day supervised chloroquine and primaquine treatments was the most effective health policy between 1957 and 2018, reducing annual malaria cases by 98% (2009–2018) when compared with 1957–1968. We also found that effective malaria reduction policies have been sensitive to natural catastrophes and extreme climatic events, both of which have increased malaria transmission in Costa Rica. Currently, outbreaks follow malaria importation into vulnerable areas of Costa Rica. This highlights the need to timely diagnose and treat malaria, while improving living standards, in the affected areas.

In this study, a microsporidian pathogen of the date moth (Apomyelois (Ectomyelois) ceratoniae, Zeller, 1839) also known as the carob moth, is described based on light microscopy, ultrastructural characteristics and comparative molecular analysis. The pathogen infects the gut and hemolymph of A. ceratoniae. All development stages are in direct contact with the host cell cytoplasm. Fresh spores with nuclei arranged in a diplokaryon are oval and measured 3.29 ± 0.23 μm (4.18–3.03 μm, n = 200) in length and 1.91 ± 0.23 μm (2.98–1.66 μm, n = 200) in width. Spores stained with Giemsa's stain measured 3.11 ± 0.31 μm (3.72–2.41 μm, n = 150) in length and 1.76 ± 0.23 μm (2.16–1.25 μm, n = 150) in width. Spores have an isofilar polar filament with 10-12 coils. An 1110 bp long alignment of the current microsporidium showed an SSU rRNA gene difference of only 0.0009, corresponding to >99.91% sequence similarity with Nosema fumiferanae, while RPB1 gene sequences were 98.03% similar within an alignment of 969 bp. All morphological, ultrastructural and molecular features indicate that the microsporidian pathogen of A. ceratoniae is the new isolate of the N. fumiferanae and is named here as Nosema fumiferanae TY61.

Essential oils (EOs) are considered a new class of ecological products aimed at the control of insects for industrial and domestic use; however, there still is a lack of studies involving the control of fleas. Ctenocephalides felis felis, the most observed parasite in dogs and cats, is associated with several diseases. The aim of this study was to evaluate the in vitro activity, the establishment of LC50 and toxicity of EOs from Alpinia zerumbet (Pers.) B. L. Burtt & R. M. Sm, Cinnamomum spp., Laurus nobilis L., Mentha spicata L., Ocimum gratissimum L. and Cymbopogon nardus (L.) Rendle against immature stages and adults of C. felis felis. Bioassay results suggest that the method of evaluation was able to perform a pre-screening of the activity of several EOs, including the discriminatory evaluation of flea stages by their LC50. Ocimum gratissimum EO was the most effective in the in vitro assays against all flea stages, presenting adulticide (LC50 = 5.85 μg cm−2), ovicidal (LC50 = 1.79 μg cm−2) and larvicidal (LC50 = 1.21 μg cm−2) mortality at low doses. It also presented an excellent profile in a toxicological eukaryotic model. These findings may support studies involving the development of non-toxic products for the control of fleas in dogs and cats.

Cysticercus tenuicollis as metacestode of Taenia hydatigena is the most prevalent taeniid species in livestock. Eighty-eight C. tenuicollis samples were collected from sheep (n = 44) and goats (n = 44) of the northern Iran from 2015 to 2016. The isolated parasites were characterized by morphometric keys. The DNA of the larval stage was extracted, amplified and sequenced targeting mitochondrial 12S rRNA and Cox 1 markers. A significant difference in larval rostellar hook length was observed in 12S rRNA haplotypes. Analysis of molecular variance of 12S rRNA indicated a moderate genetic diversity in the C. tenuicollis isolates. The pairwise sequence distance of C. tenuicollis showed an intra-species diversity of 0.3–0.5% and identity of 99.5–100%. Using the 12S rRNA sequence data we found a moderate genetic difference (Fst; 0.05421) in C. tenucollis isolates collected from livestock of the northern and southeastern regions of Iran. We concluded that the genetic variants of C. tenuicollis are being undoubtedly distributing mostly in different parts of Iran. Further studies with a larger number of T. hydatigena isolates collected from various intermediate and definitive hosts are needed to study this evolutionary assumption and also to determine the apparent genetic differences observed in the studied regions.

Understanding factors that influence the spatial and temporal distributions of blood parasites is important to help predict how host species and their parasites may respond to global change. Factors that may influence parasite distributions are land cover and host dispersal patterns, which may result in exposure of a host to novel parasites, or escape from parasites of their origin. We screened golden-winged warblers from across the United States and Canada for blood parasites, and investigated whether land-use patterns or host dispersal affected the prevalence and composition of haemosporidian assemblages. Parasite prevalence varied strongly with study area, and areas with high agricultural cover had a significantly higher prevalence of Leucocytozoon and Parahaemoproteus parasites. Lineages of Parahaemoproteus and Leucocytozoon were genetically differentiated among study areas, and prevalence and composition of parasite assemblages indicated an increase in parasite prevalence and accumulation of unique parasite lineages from the southeast to the northwest. This matches the historical range expansion and natal dispersal patterns of golden-winged warblers, and suggests that golden-winged warblers may have been sensitive to novel parasites as they dispersed. The high prevalence and diversity of parasite lineages in the north-west extent of their breeding range (Manitoba) indicates that this population may face unique pressures.

Myxozoans are parasitic, microscopic cnidarians that have retained the phylum-characteristic stinging capsules called nematocysts. Free-living cnidarians, like jellyfish and corals, utilize nematocysts for feeding and defence, with discharge powered by osmotic energy. Myxozoans use nematocysts to anchor to their fish hosts in the first step of infection, however, the discharge mechanism is poorly understood. We used Myxobolus cerebralis, a pathogenic myxozoan parasite of salmonid fishes, and developed two assays to explore the nature of its nematocyst discharge. Using parasite actinospores, the infectious stage to fish, we stimulated discharge of the nematocysts with rainbow trout mucus in vitro, in solutions enriched with chloride salts of Na+, K+, Ca2+ and Gd3+, and quantified discharge using microscopy. We then used quantitative polymerase chain reaction to evaluate the in vivo effects of these treatments, plus Mg2+ and the common aquaculture disinfectant KMnO₄, on the ability of M. cerebralis actinospores to infect fish. We found that Mg2+ and Gd3+ reduced infection in vivo, whereas Na+ and K+ over-stimulated nematocyst discharge in vitro and reduced infection in vivo. These findings align with nematocyst discharge behaviour in free-living Cnidaria, and suggest phylum-wide commonalties, which could be exploited to develop novel approaches for controlling myxozoan diseases in aquaculture.

This study provides insights about the diversity, prevalence and distribution of alpine wild galliformes gastrointestinal parasite community, trying to fill a gap in the scientific information currently available in scientific literature. The analysis included three host species: 77 rock partridge (Alectoris graeca saxatilis), 83 black grouse (Tetrao tetrix tetrix) and 26 rock ptarmigan (Lagopus muta helveticus) shot during the hunting seasons 2008–2015. Parasites isolated were Ascaridia compar, Capillaria caudinflata and cestodes. The rock ptarmigan was free from gastrointestinal parasites, whereas the most prevalent helminth (37%) was A. compar in both black grouse and rock partridge. C. caudinflata occurrence was significantly higher in black grouse (prevalence = 10%, mean abundance = 0.6 parasites/sampled animal) than in rock partridge (prevalence = 1.20%, mean abundance = 0.01 parasites/sampled animal). Significant differences were detected among hunting districts. A. compar was found with a significant higher degree of infestation in the hunting districts in the northern part of the study area whereas cestodes abundance was higher in Lanzo Valley. Quantitative analysis of risk factors was carried out using a generalized linear model (GLM) only on the most common parasite (A. compar). Latitude was the only factors associated with infestation risk (OR = 52.4). This study provides information on the composition and variability of the parasite community in the alpine Galliformes species.