Epidemiology, diagnosis, treatment, and control of trichinellosis

Superb bio-effectiveness of Cobalt (II) phthalocyanine and Ag NPs adorned Sm-doped ZnO nanorods/cuttlefish bone to annihilate Trichinella spiralis muscle larvae and adult worms: In-vitro evaluation

Herein, innovative biocides are designed for the treatment of Trichinella spiralis muscle larvae (ML) and adult worms. Samarium-doped ZnO nanorods (Sm-doped ZnO) are stabilized onto the laminar structure of cuttlefish bone (CB) matrix and adorned by either Ag NPs or cobalt phthalocyanine (CoPc) species. Physicochemical characteristics of such nanocomposites are scrutinised. Adorning of Sm-doped ZnO/CB with Ag NPs shortens rod-like shaped Sm-doped ZnO nanoparticles and accrues them, developing large-sized detached patches over CB moiety. Meanwhile, adorning of Sm-doped ZnO/CB by CoPc species degenerates CB lamellae forming semi-rounded platelets and encourages invading of Sm-doped ZnO nanorods deeply inside gallery spacings of CB. Both nanocomposites possess advanced parasiticidal activity, displaying quite intoxication for ML and adult worms (≥88% mortality) within an incubation period of <48 h at concentrations around 200 μg/ml. CoPc@Sm-doped ZnO/CB nanocomposite exhibits faster killing efficiency of adult worms than that of Ag@Sm-doped ZnO/CB at a concentration of ∼75 μg/ml showing entire destruction of parasite after 24 h incubation with the former nanocomposite and just 60% worm mortality after 36 h exposure to the later one. Morphological studies of the treated ML and adult worms show that CoPc@Sm-doped ZnO/CB exhibits a destructive impact on the parasite body, creating featureless and sloughed fragments enriched with intensive vacuoles. Hybridization of cuttlefish bone lamellae by CoPc species is considered a springboard for fabrication of futuristic aggressive drugs against various food- and water-borne parasites.

From wildlife to humans: The global distribution of Trichinella species and genotypes in wildlife and wildlife-associated human trichinellosis

Zoonotic nematodes of the genus Trichinella are foodborne parasites that have a global distribution in wild carnivores and omnivores, with spillover and spillback into domestic livestock and people, with concomitant trade and health consequences. Historically, most human cases were linked to domestic pigs infected with Trichinella spiralis, but under current high biosecurity swine production in many countries, wildlife have become a more important source of human trichinellosis. The aim of this review is to update the global distribution of Trichinella species and genotypes reported in wildlife, as well as reported human outbreaks from the consumption of wildlife. Using several online databases and by "snowballing" references, hundreds of reports of Trichinella spp. in wildlife published between January 1991 and December 2023 provide an important update to the host and geographic range for each of the recognized 13 species/genotypes, grouped by continent. Surveillance effort was highest in Europe and North America, while Africa, Asia, Central and South America have had limited surveillance, in some instances with human cases serving as sentinels of transmission in a region. Dozens of human outbreaks are described, with wild boars (Sus scrofa) being the most frequently implicated wildlife species in human outbreaks globally. Bears are an important source of infection in North America, for wildlife tourism, and importation of bear meat has also been implicated in multicountry outbreaks. The largest study limitation was the dearth of molecular identification of larvae in both wildlife surveillance studies and human outbreaks, particulary in under-studied regions. We highlight the need for enhanced molecular epidemiological approaches to outbreaks of this important foodborne parasite, and emphasize the need for a One Health approach to manage Trichinella spp. which transmit among terrestrial and marine wildlife (including migratory birds), pigs, horses, and people, often across large geographic scales and borders.

Light microscopical and parasitological analyses revealed the beneficial effects of silver nanoparticles and various myrrh extracts against Trichinella spiralis infection in mice

Trichinella spiralis infection is a food-borne zoonotic disease caused by nematodes that dwell in the tissues, presenting a significant public health concern. This study aimed to evaluate the effectiveness of different treatments including silver nanoparticles (AgNPs), myrrh biosynthesized AgNPs "AgNPs synthesized using plant-based green technologies", myrrh extract, and myrrh essential oil, as alternative treatments against T. spiralis infection. Parasitological, histopathological, and cytotoxicity assessments were conducted to investigate the effects of various concentrations of these treatments in reducing the populations of adult worms and larvae during both the intestinal and muscular phases of T. spiralis-infected mice. The results showed that the highest antihelminthic efficacy against the intestinal phase of T. spiralis was achieved by myrrh extract (86.66%), followed closely by AgNPs (84.96%) and myrrh AgNPs (82.51%) at higher concentrations (800 mg/kg for myrrh extract, 40 μg/mL for AgNPs, and 40 μg/mL for myrrh AgNPs). While the group treated with myrrh essential oil showed the lowest percentage of adult reduction (78.14%). However, all treatments demonstrated comparable effects in reducing the larvae population in the muscle phase. Histopathological examination of the tissues revealed compelling evidence of the effectiveness of AgNPs, particularly when prepared with myrrh. Additionally, a comprehensive assessment of the cytotoxicity of AgNPs indicated low toxicity levels. This study supports that AgNPs synthesized using plant-based green technologies hold therapeutic potential for the treatment of T. spiralis infection. These findings present a promising avenue for the development of novel antiparasitic drugs that are both effective and safe. RESEARCH HIGHLIGHTS: Myrrh extract has the highest antihelminthic efficacy against the intestinal phase of T. spiralis. Histopathological examination of the tissues revealed compelling evidence of the effectiveness of AgNPs, particularly when prepared with myrrh. During intestinal phase of T. spiralis, varying levels of nanoparticle precipitation were detected in the liver, brain, lung, and intestine. During the muscular phase, the highest amount of AgNPs precipitation was detected in the liver, followed by the brain, and lung.

Human parasitic infections of the class Adenophorea: global epidemiology, pathogenesis, prevention and control

BACKGROUND

Human parasitic infections caused by Adenophorean nematodes encompass a range of diseases, including dioctophymiasis, trichuriasis, capillariasis, trichinellosis, and myositis. These infection can result in adverse impacts on human health and cause societal and economic concerns in tropical and subtropical regions.

METHODS

This review conducted searches in PubMed, Embase and Google Scholar for relevant studies that published in established databases up to April 26, 2024. Studies that focused on the common morphology, life cycle, disease distribution, clinical manifestations, and prevention and control strategies for Adenophorean parasitic diseases in humans were included.

RESULTS

Adenophorean nematodes exhibit shared morphological characteristics with a four-layered cuticle; uninucleate epidermal cells; pseudocoelom with six or more coelomocytes; generally three caudal glands; five esophageal glands; two testes in males with median-ventral supplementary glands in a single row; tail in males rarely possessing caudal alae; amphids always postlabial; presence of cephalic sensory organs; absence of phasmids; and a secretory-excretory system consisting of a single ventral gland cell, usually with a non-cuticularized terminal duct. Humans play two important roles in the life cycle of the nematode class, Adenophorea: 1) as a definitive host infected by ingesting undercooked paratenic hosts, embryonated eggs, infective larvae in fish tissue and meat contaminated with encysted or non-encysted larvae, and 2) as an accidental host infected by ingesting parasitic eggs in undercooked meat. Many organs are targeted by the Adenophorean nematode in humans such as the intestines, lungs, liver, kidneys, lymphatic circulation and blood vessels, resulting in gastrointestinal problems, excessive immunological responses, cell disruption, and even death. Most of these infections have significant incidence rates in the developing countries of Africa, Asia and Latin America; however, some parasitic diseases have restricted dissemination in outbreaks. To prevent these diseases, interventions together with education, sanitation, hygiene and animal control measures have been introduced in order to reduce and control parasite populations.

CONCLUSIONS

The common morphology, life cycle, global epidemiology and pathology of human Adenophorean nematode-borne parasitic diseases were highlighted, as well as their prevention and control. The findings of this review will contribute to improvement of monitoring and predicting human-parasitic infections, understanding the relationship between animals, humans and parasites, and preventing and controlling parasitic diseases.

ACV with/without IVM: a new talk on intestinal CDX2 and muscular CD34 and Cyclin D1 during Trichinella spiralis infection

The current study assessed the efficacy of Acyclovir (ACV) and Ivermectin (IVM) as monotherapies and combined treatments for intestinal and muscular stages of Trichinella spiralis infection. One-hundred Swiss albino mice received orally 250 ± 50 infectious larvae and were divided into infected-untreated (Group-1), IVM-treated (Group-2), ACV-treated (Group-3), combined IVM+ACV (Group-4), and healthy controls (Group-5). Each group was subdivided into subgroup-A-enteric phase (10 mice, sacrificed day-7 p.i.) and subgroup-B-muscular phase (10 mice, sacrificed day-35 p.i.). Survival rate and body weight were recorded. Parasite burden and intestinal histopathology were assessed. In addition, immunohistochemical expression of epithelial CDX2 in the intestinal phase and CyclinD1 as well as CD34 in the muscular phase were evaluated. Compared, IVM and ACV monotherapies showed insignificant differences in the amelioration of enteric histopathology, except for lymphocytic counts. In the muscle phase, monotherapies showed variable disruptions in the encapsulated larvae. Compared with monotherapies, the combined treatment performed relatively better improvement of intestinal inflammation and reduction in the enteric and muscular parasite burden. CDX2 and CyclinD1 positively correlated with intestinal inflammation and parasite burden, while CD34 showed a negative correlation. CDX2 positively correlated with CyclinD1. CD34 negatively correlated with CDX2 and CyclinD1. IVM +ACV significantly ameliorated CDX2, CyclinD1, and CD34 expressions compared with monotherapies. Conclusion. T. spiralis infection-associated inflammation induced CDX2 and CyclinD1 expressions, whereas CD34 was reduced. The molecular tumorigenic effect of the nematode remains questionable. Nevertheless, IVM +ACV appeared to be a promising anthelminthic anti-inflammatory combination that, in parallel, rectified CDX2, CyclinD1, and CD34 expressions.

Antiparasitic Activity of Enterocin M and Durancin-like from Beneficial Enterococci in Mice Experimentally Infected with Trichinella spiralis

Beneficial/probiotic strains protect the host from pathogens by competitive displacement and production of antibacterial substances, i.e., bacteriocins. The antiparasitic potential of bacteriocins/enterocins and their producing strains in experimental murine trichinellosis were tested as a new therapeutic strategy. Enterocin M and Durancin-like and their producers Enterococcus faecium CCM8558 and Enterococcus durans ED26E/7 were administered daily to mice that were challenged with Trichinella spiralis. Our study confirmed the antiparasitic effect of enterocins/enterococci, which reduced the number of adults in the intestine (Enterocin M-43.8%, E. faecium CCM8558-54.5%, Durancin-like-16.4%, E. durans ED26E/7-35.7%), suppressed the Trichinella reproductive capacity ex vivo (Enterocin M-61%, E. faecium CCM8558-74%, Durancin-like-38%, E. durans ED26E/7-66%), and reduced the number of muscle larvae (Enterocin M-39.6%, E. faecium CCM8558-55.7%, Durancin-like-15%, E. durans ED26E/7-36.3%). The direct effect of enterocins on Trichinella fecundity was documented by an in vitro test in which Durancin-like showed a comparable reducing effect to Enterocin M (40-60%) in contrast to the ex vivo test. The reducing activity of T.spiralis infection induced by Enterocin M was comparable to its strain E. faecium CCM8558; Durancin-like showed lower antiparasitic activity than its producer E. durans ED26E/7.

Nanocurcumin: A Promising Therapeutic Candidate for Experimental Trichinellosis

In our pursuit of an alternative drug against Trichinella spiralis, we assessed the effectiveness of nanocurcumin in alleviating pathogenesis, parasitological factors, MMP-9 levels, and its expression in the enteral and parenteral phases of infection. The nanocurcumin particles, with a spherical shape and a size of 100 ± 20 nm, were used in the study. Eighty mice were divided into four groups: the control group, the untreated infected group, the nanocurcumin-treated group, and the albendazole-treated group. The nanocurcumin-treated group exhibited a statistically significant increase in the percentage of lymphocytes, along with a reduction in neutrophils, monocytes, and eosinophils compared to the untreated, infected group. Both the nanocurcumin (87.2 and 97.3%) and the albendazole-treated groups (99.8 and 98.2%) showed a significant reduction in the mean number of intestinal worms and encysted larvae, respectively. The treated groups exhibited normal intestinal villi, suppression of the inflammatory process, and fewer instances of degenerated larvae in the diaphragm and muscle compared to the untreated, infected group. Immunohistochemistry and ELISA analyses revealed a significant downregulation of MMP-9 levels in the intestines and muscles of the treated groups. Our data demonstrate that nanocurcumin contains highly versatile molecules capable of modulating biological activity against inflammation and its pathway markers.

Trichinella Infection in Culled Wild Boar (Sus scrofa) from El Palmar National Park, Argentina, and Exposure Risk in Humans and Dogs Consuming Wild Boar Meat

Trichinellosis is a foodborne disease caused by ingestion of raw or undercooked meat containing Trichinella spp. larvae. Consumption of wild boar (Sus scrofa) meat represents an important source of human trichinellosis worldwide. In El Palmar National Park (EPNP), Argentina, invasive alien wild boars are controlled and meat from culled animals is released for public consumption following on-site artificial digestion (AD) testing. Meat trimmings and offal from the control program are often used as food for dogs (Canis familiaris). We evaluated infection and exposure to Trichinella spp. in wild boars from EPNP, as well as exposure to Trichinella spp. and associated risk factors in dogs and human consumers of wild boar meat. Trichinella spp. larvae were detected in muscle samples from 5/49 wild boars by AD (10.2%; 95% confidence interval [CI], 3.8%-23%), with a mean burden of 0.24 larvae per gram (lpg; range, 0.06-0.95 lpg). Anti-Trichinella antibodies were not detected in wild boar serum samples (n=42). In dogs, 12/34 were seropositive to Trichinella spp. (35.29%; 95%, CI, 20.3%-53.5%). Immunoglobulin (Ig) G antibodies were not detected in human serum samples (n=63). Our results reveal the presence, albeit at low prevalence, of Trichinella spp. in wild boars and exposure in dogs fed game offal. These findings suggest that the low prevalence and parasitic load in wild boars, together with the best practices applied by EPNP culling program personnel, contribute to keeping the risk of infection in people low. The dog results highlight that the parasite is circulating in the area, and therefore the risk of infection is not negligible. We recommend the implementation of an animal surveillance strategy in order to monitor the evolution of this zoonosis in the study area.

Detection of Spirocerca lupi and an unknown Trichinella-like nematode in raccoon (Procyon lotor)

The raccoon Procyon lotor (Carnivora: Procyonidae) is an invasive species of growing importance for the introduction of alien pathogens or as additional hosts for autochthonous pathogens in Europe, including zoonotic parasites. As the population is steadily increasing and outcompeting the red fox (Vulpes vulpes) in Germany, the consumption of raccoon meat raises concerns about pathogens they may transmit. Therefore the presence of Trichinella larvae was here investigated in muscle samples (n = 904) of raccoons from northern Germany. No Trichinella larvae were found, thus confirming the general low occurrence of this parasite in Germany. However, Spirocerca lupi (n = 12) and an unidentified Trichinella-like nematode (n = 1) were accidently detected in the examined samples. The first is not a zoonotic parasite but has a high veterinary relevance as it can cause severe diseases in dogs. It is the first documented autochthonous infection of this nematode in Germany. The larvae of an unidentified Trichinella-like nematode were found in high abundance in all examined muscles of one raccoon, though they could not be identified to species level. Histological investigation revealed intramuscular cystic structures. This is the largest study investigating muscular parasites of raccoons in Europe so far, which suggests that this invasive animal species is infected by S. lupi and by a yet unknown Trichinella -like parasite.

Diversity of Trichinella species in carnivores from Bosnia and Herzegovina

BACKGROUND

In Bosnia and Herzegovina, domestic and wild carnivores represent a significant driver for the transmission and ecology of zoonotic pathogens, especially those of parasitic aetiology. Nevertheless, there is no systematic research of Trichinella species in animals that have been conducted in Bosnia and Herzegovina, even though trichinellosis is considered the most important parasitic zoonosis. The available results of the few studies carried out in Bosnia and Herzegovina are mainly related to the confirmation of parasitic larvae in the musculature of domestic pigs and wild boars or data related to trichinellosis in humans. The objective of our study was to present the findings of a comprehensive investigation into the species composition of Trichinella among 11 carnivorous species within the territory of Bosnia and Herzegovina, as follows: red fox (Vulpes vulpes), grey wolf (Canis lupus), brown bear (Ursus arctos), wildcat (Felis silvestris), pine marten (Martes martes), European badger (Meles meles), weasel (Mustela nivalis), European polecat (Mustela putorius), Eurasian lynx (Lynx lynx), but also dog (Canis lupus familiaris) and cat (Felis catus).

RESULTS

In the period 2013-2023, carnivore musculature samples (n = 629), each consisting of 10 g of muscle tissue, were taken post-mortem and individually examined using the artificial digestion method. In the positive samples (n = 128), molecular genotyping and identification of parasitic larvae of Trichinella spp. were performed using a PCR-based technique up to the species/genotype level. Positive samples were used for basic PCR detection of the genus Trichinella (rrnS rt-PCR technique) and genotyping (rrnl-EVS rt-PCR technique). The Trichinella infection was documented for the first time in Bosnia and Herzegovina among red foxes, grey wolves, brown bears, dogs, badgers and Eurasian lynx, with a frequency rate of 20.3%. Additionally, the presence of T. britovi infection was newly confirmed in Bosnia and Herzegovina, marking the initial documented cases. Furthermore, both T. britovi and T. pseudospiralis infections were observed in the wildcat population, whereas T. britovi and T. spiralis infections were detected in pine martens. Consistent with previous research, our findings align particularly regarding carnivores, with data from other countries such as Germany, Finland, Romania, Poland and Spain, where T. britovi exhibits a wider distribution (62.5-100%) compared to T. spiralis (0.0-37.5%). T. britovi is more common among sylvatic carnivores (89.0%), while T. spiralis prevails in wild boars (62.0%), domestic swine (82.0%) and rodents (75.0%).

CONCLUSION

The results of our study represent the first molecular identification of species of the genus Trichinella in Bosnia and Herzegovina. Additionally, our findings underscore the necessity for targeted epidemiological studies to thoroughly assess trichinellosis prevalence across diverse animal populations. Considering the relatively high frequency of trichinellosis infection in investigated animal species and its public health implications, there is an evident need for establishing an effective trichinellosis surveillance system in Bosnia and Herzegovina.

Nematocidal activity of chitosan nanoparticles conjugated with albendazole against the enteral and parenteral phases of trichinosis in experimentally infected mice

Trichinosis is a serious parasitic zoonotic disease caused mainly by Trichinella spiralis. The used drugs for treatment of trichinosis showed limited bioavailability and high degree of resistance. Moreover, they have a very poor effect in treatment of encysted larvae. Therefore, there is a need for development of new agents which help in improving the bioavailability of the used drugs and enable them to reach different tissues. This study was designed to assess the use of chitosan nanoparticles (CSNPs) in conjugation with full and half dose albendazole (ABZ) in treatment of intestinal and muscular trichinosis. Albino mice (84 mice) were used to evaluate the efficacy of drugs and divided into seven groups; I: control, II: ABZ (50 mg/kg) treated, III: ABZ (25 mg/kg) treated, IV: ABZ (50 mg/kg) conjugated CSNPs treated, V: ABZ (25 mg/kg) conjugated CSNPs treated, VI: CS treated and VII: CSNPs treated. Parasitological and histopathological examinations were used to evaluate the therapeutic efficacy of the used drugs. Results showed significant reduction of adult Trichinella extracted from intestine of all ABZ treated groups either conjugated or not with the highest reduction rate in group IV followed by group V with percentage of reduction of 99.33% and 98.11%, respectively and marked improvement of histopathological examination. Also, results showed significant reduction of Trichinella larvae extracted from muscles of group IV, V and VII with the highest reduction rate in group IV with percentage of reduction of 100% in muscle larvae and marked improvement of histopathological examination. It was concluded that albendazole full dose conjugated chitosan nanoparticles can be a good candidate drug for treating both intestinal and muscular trichinosis.

The neuroprotective potential of curcumin on T. Spiralis infected mice

BACKGROUND

Trichinella spiralis can affect the brain by inducing inflammatory and vascular changes. Drug management with the antiparasitic drug albendazole can be enhanced by natural compounds such as curcumin. The potential benefit of curcumin as an adjuvant to albendazole in the management of cerebral affection during experimental T. spiralis infection was evaluated. Animals received either curcumin 150 mg/Kg, albendazole 50 mg/Kg or a combination of both drugs. Animal groups receiving treatment were compared with infected and non-infected control groups. Blood levels of reduced glutathione (GSH) and dopamine were measured, and brain tissue expression of cyclooxygenase-2 enzyme (COX-2) and CD34 was assessed by immunohistochemistry.

RESULTS

T. spiralis infection resulted in a state of oxidative stress, which was improved by albendazole and curcumin. Also, both drugs restored the peripheral dopamine level, which was decreased in infected non-treated mice. Curcumin was also found to be efficient in improving brain pathology and reducing local COX-2 and CD 34 expression.

CONCLUSIONS

Inflammatory and pathological changes during neurotrichinosis can be improved by the addition of curcumin to conventional anti-parasitic drugs.

Seroepidemological investigation of Toxoplasma gondii and Trichinella spp. in pigs reared by tribal communities and small-holder livestock farmers in Northeastern India

Toxoplasma gondii and Trichinella spp. are critical tissue-dwelling foodborne zoonotic parasites associated with pork consumption and pig rearing. Despite being a major pig-rearing region in the country, Northeastern India has not undergone any investigation regarding the presence of T. gondii and Trichinella spp. in pigs. Therefore, this study aims to determine the seroprevalence of T. gondii and Trichinella spp. and identify associated risk factors in pigs reared by tribal communities and small-holder livestock farmers in the northeastern region of India. In a cross-sectional serological survey, 400 pigs from 400 households across five northeastern states of India underwent testing for the seroprevalence of porcine toxoplasmosis and trichinellosis. Serum samples (80 from each state) were analyzed using commercially available ELISA assays. Data on backyard farm characteristics and various management aspects were collected, and risk factors linked with prevalence were analyzed through univariate and multivariate logistic regression analysis. The findings revealed that the apparent and true prevalence of anti-T. gondii antibodies were 45% (40.12-49.88, 95% CI) and 45.7% (40.7-50.69, 95% CI), respectively. As for anti- Trichinella antibodies, both the apparent and true prevalence were 0.75% (-0.1-1.6, 95% CI). The univariate and multivariate analyses indicated that age above 24 months (OR 7.20, 95% CI 2.45-23.71), exposure to cats (OR = 5.87, 95% CI 2.55-14.05), and farms operating for breeding purposes (OR = 5.60, 95% CI 3.01-11.04) were significant risk factors associated with the seroprevalence of T. gondii. This study marks the initial documentation of the seroprevalence of T. gondii and Trichinella spp. in pigs reared by tribal communities in Northeastern India. The results emphasize the significance of these parasites as foodborne zoonotic threats in the region, potentially posing substantial public health risks, especially within tribal and rural communities. The insights derived from this research could be valuable in formulating targeted preventive and control strategies against T. gondii and Trichinella spp. in pigs, not only in this region but also in areas with similar rearing practices.

Identification of Sarcocystis and Trichinella Species in Muscles of Gray Wolf (Canis lupus) from Lithuania

Apicomplexan Sarcocystis and Trichinella nematodes are food-borne parasites whose life cycle is carried-out in various wildlife and domestic animals. The gray wolf (Canis lupus) is an apex predator acting as an ecosystem engineer. This study aimed to identify the species of Sarcocystis and Trichinella found in the muscles of gray wolves in Lithuania. During the 2017-2022 period, diaphragm, heart, and hind leg samples of 15 animals were examined. Microscopical analysis showed the presence of two types of Sarcocystis parasites in 26.7% of the analyzed muscle samples. Based on the sequencing of five loci, nuclear 18S rDNA, 28S rDNA, ITS1, mitochondrial cox1, and apicoplast rpoB, S. arctica, and S. svanai were identified. The current work presents the first report of S. svanai in gray wolf. Phylogenetically, S. svanai clustered together with S. lutrae, infecting various carnivorans, and S. arctica was most closely related to S. felis from domestic cats. Trichinella spp. were found in 12 gray wolves (80%). For the first time, Trichinella species were molecularly identified in gray wolves from Lithuania. Trichinella britovi was confirmed in all of the isolated Trichinella larvae using a multiplex PCR. Gray wolves in Lithuania may serve as a major source of zoonotic pathogens due to the presence of these parasites.

Trichinella spiralis: A new parasitic target for curcumin nanoformulas in mice models

Trichinosis spiralis is a global disease with significant economic impact. Albendazole is the current-treatment. Yet, the world-widely emerging antimicrobial resistance necessitates search for therapeutic substitutes. Curcumin is a natural compound with abundant therapeutic benefits. This study aimed to evaluate the potential of crude-curcumin, chitosan and for the first time curcumin-nano-emulsion and curcumin-loaded-chitosan-nanoparticles against Trichinella spiralis adults and larvae in acute and chronic trichinosis models. Trichinosis spiralis was induced in 96 Swiss-albino mice. Infected mice were divided into 2 groups. Group I constituted the acute model, where treatment started 2 h after infection for 5 successive days. Group II constituted the chronic model, where treatment started at the 30th day-post-infection and continued for 10 successive days (Refer to graphical abstract). Each group contained 8 subgroups that were designated Ia-Ih and IIa-IIh and included; a; Untreated-control, b; Albendazole-treated (Alb-treated), c; Crude-curcumin-treated (Cur-treated), d; Curcumin-nanoemulsion-treated (Cur-NE-treated), e; Albendazole and crude-curcumin-treated (Alb-Cur-treated), f; Albendazole and curcumin-nanoemulsion-treated (Alb-Cur-NE-treated), g; Chitosan-nanoparticles-treated (CS-NPs-treated) and h; Curcumin-loaded-chitosan-nanoparticles-treated (Cur-CS-NPs-treated). Additionally, six mice constituted control-uninfected group III. The effects of the used compounds on the parasite tegument, in-vivo parasitic load-worm burden, local pathology and MDA concentration in small intestines of acutely-infected and skeletal muscle of chronically-infected mice were studied. Results showed that albendazole was effective, yet, its combination with Cur-NE showed significant potentiation against adult worms and muscle larvae and alleviated the pathology in both models. Cur-CS-NPs exhibited promising results in both models. Crude-curcumin showed encouraging results especially against muscle larvae on long-term use. Treatments effectively reduced parasite load, local MDA level and CD31 expression with anti-inflammatory effect in intestine and muscle sections.

Pumpkin seeds (Cucurbita pepo subsp. ovifera) decoction promotes Trichinella spiralis expulsion during intestinal phase via "Weep and Sweep" mechanism

Trichinosis is a zoonotic disease of communal health concern as it instigated human outbreaks in several countries. Besides, the development of resistance, traditional therapy has numerous antagonistic effects. Thereby, finding efficient natural alternatives is required. In comparison to albendazole, this study evaluated the impact of pumpkin decoction on Trichinella spiralis in experimentally infected mice. The anthelmintic action of pumpkin decoction (500 mg/kg) was determined using T. spiralis infected mice in enteric phase for 5 days. Pumpkin decoction anthelmintic activity fortified by mixing with honey (1:1). Pumpkin decoction and Pumpkin decoction-honey mixture were evaluated by comprising with reference drug, albendazole (50 mg/kg). The T. spiralis adult count was significantly lower in all treated groups, with the pumpkin decoction-honey mixture showing the largest reduction (83.2%) when compared to the infected group (P ≤ 0.001). The intestinal histological changes and the level of COX-2 expression in the intestinal tissue were both significantly reduced in the same group. The pumpkin decoction improved the immune response, as evidenced by a significant decrease in nitric oxide (NO) and tumor necrosis factor (TNF-α) and a significant increase in the expression of the transforming growth factor (TGF-1β) and interleukin-17 (IL-17). The pumpkin decoction's anthelmintic action was facilitated by the TGF-1β and IL-17-driven Weep and Sweep mechanism. Both administration of pumpkin decoction beside honey showed the best treatment group that resulted in high infection reduction besides amelioration of biochemical markers and restoration of histological to normal state. In conclusion, pumpkin decoction is highly effective against T. spiralis which could be a promising alternative herbal drug and the pumpkin decoction effect was higher in the case of combination with honey.

Application of a recombinant novel trypsin from Trichinella spiralis for serodiagnosis of trichinellosis

BACKGROUND

The excretory/secretory (ES) antigen of Trichinella spiralis muscle larvae (ML) is currently the most widely used diagnostic antigen to detect T. spiralis infection. However, this antigen has certain drawbacks, such as a complicated ES antigen preparation process and lower sensitivity during the early phase of infection. The aim of this study was to investigate the features of a novel T. spiralis trypsin (TsTryp) and evaluate its potential diagnostic value for trichinellosis.

METHODS

The TsTryp gene was cloned and recombinant TsTryp (rTsTryp) expressed. Western blotting and an enzyme-linked immunosorbent assay (ELISA) were performed to confirm the antigenicity of rTsTryp. The expression pattern and distribution signature of TsTryp at various life-cycle stages of T. spiralis were analyzed by quantitative PCR, western blotting and the immunofluorescence test. An ELISA with rTsTryp and ML ES antigens was used to detect immunoglobulins G and M (IgG, IgM) in serum samples of infected mice, swine and humans. The seropositive results were further confirmed by western blot with rTsTryp and ML ES antigens.

RESULTS

TsTryp expression was observed in diverse T. spiralis life-cycle phases, with particularly high expression in the early developmental phase (intestinal infectious larvae and adults), with distribution observed mainly at the nematode outer cuticle and stichosome. rTsTryp was identified by T. spiralis-infected mouse sera and anti-rTsTryp sera. Natural TsTryp protease was detected in somatic soluble and ES antigens of the nematode. In mice infected with 200 T. spiralis ML, serum-specific IgG was first detected by rTsTryp-ELISA at 8 days post-infection (dpi), reaching 100% positivity at 12 dpi, and first detected by ES-ELISA at 10 dpi, reaching 100% positivity at 14 dpi. Specific IgG was detected by rTsTryp 2 days earlier than by ES antigens. When specific IgG was determined in serum samples from trichinellosis patients, the sensitivity of rTsTryp-ELISA and ES antigens-ELISA was 98.1% (51/52 samples) and 94.2% (49/52 samples), respectively (P = 0.308), but the specificity of rTsTryp was significantly higher than that of ES antigens (98.7% vs. 95.4%; P = 0.030). Additionally, rTsTryp conferred a lower cross-reaction, with only three serum samples in total testing positive from 11 clonorchiasis, 20 cysticercosis and 24 echinococcosis patients (1 sample from each patient group).

CONCLUSIONS

TsTryp was shown to be an early and highly expressed antigen at intestinal T. spiralis stages, indicating that rTsTryp represents a valuable diagnostic antigen for the serodiagnosis of early Trichinella infection.

New Geographic Records for Trichinella nativa and Echinococcus canadensis in Coyotes (Canis latrans) from Insular Newfoundland, Canada

Coyotes (Canis latrans) rapidly expanded across North America during the 20th century and in 1987 colonized insular Newfoundland, Canada. Their arrival brought the potential for new predator-prey interactions and the potential for transmission of parasites to naïve populations. Trichinella spp. and Echinococcus spp. are zoonotic parasites not previously reported from the island of Newfoundland, Canada. Muscle samples (diaphragm and tongue) from 153 coyotes and feces from 35/153 coyotes were collected. Larvae of Trichinella spp. were recovered by muscle digestion from 6/153 coyotes (3.9%) and identified using multiplex PCR and Sanger sequencing as T. nativa. Fecal samples were screened for DNA of Echinococcus spp. using qPCR, and intestines from positive animals were examined for adult cestodes. No fecal samples were positive for DNA of E. multilocularis, and 2/35 (5.7%) samples were positive for E. canadensis, of which one was successfully genotyped as the G10 cervid strain. Echinococcus canadensis has not previously been reported on the island of Newfoundland, historically the only region of Canada where Echinococcus spp. was not known to occur. No species of Trichinella have previously been reported on the island. Both parasites are zoonotic, and hunters, trappers, dog owners, and the general public should be aware of these new risks for public health.

Distribution and prevalence of antibodies to Trichinella spp. and Toxoplasma gondii in wild pigs (Sus scrofa) in the United States

Invasive wild pigs (Sus scrofa) are a reservoir for over 100 viral, bacterial, and parasitic pathogens that are transmissible to humans, livestock, domestic animals, and wildlife in North America. Numerous historical local surveys and results from a nation-wide survey (2006-2010) indicated that wild pigs in the United States act as reservoirs for Trichinella spp. and Toxoplasma gondii, two zoonotic pathogens of importance for human and animal health. Since that time, wild pig populations have expanded and increased in density in many areas. Population expansion of wild pigs creates opportunities for the introduction of pathogens to new areas of the country, increasing health risks. The goal of this study was to investigate the current geographic distribution and prevalence of Trichinella spp. and T. gondii antibodies in wild pigs using serum samples collected from 2014 to 2020. Serum samples from 36 states were tested for antibodies to Trichinella spp. (n = 7467) and T. gondii (n = 5984) using commercially available enzyme-linked immunosorbent assays. Seroprevalence for Trichinella spp. (12.4%, 927/7467) and T. gondii (40.8%, 2444/5984) are significantly higher compared to a previous 2006-2010 study across all regions. Results from this study also showed a lower seroprevalence (4.8%) for Trichinella spp. in the West region compared to the other regions (South: 13.4%; Midwest: 18.4%; Northeast: 19.1%). There were new detection records for antibodies to Trichinella spp. in 11 states, mostly in the West, Midwest, and Northeast regions compared to a previous study in 2014. Males and juveniles were less likely to be positive for Trichinella spp. antibodies, compared to females and older animals, respectively. Seroprevalence was similar for T. gondii across the regions (31.8-56%) with some states having particularly high seroprevalence (e.g., Hawaii 79.4% and Pennsylvania 68%). There were new T. gondii antibody detection records for 12 states, mostly in the West, Midwest, and Northeast regions. Adults were more likely than juveniles and subadults to be seropositive. These data confirm that the distribution and prevalence of antibodies for Trichinella spp. and T. gondii are increasing in the United States, likely driven by wild pig population growth and range expansion.

Original algorithms for the detection of cardiovascular involvement of neglected tropical diseases

INTRODUCTION

Neglected tropical diseases (NTDs) introduce considerable morbidity and mortality on a global scale, directly impacting over 1 billion individuals as well as their families and communities. Afflicted individuals may have limited access to resources and care in these regions, contributing to a high proportion of chronic, progressive, and systemic disease. The cardiovascular system is at particular risk of demise for several NTDs, yet remains largely unstudied due in part to the lack of robust data collection mechanisms in the most impacted regions.

AREAS COVERED

The present review is a part of the Neglected Tropical Diseases and other Infectious Diseases affecting the Heart (NET-Heart) Project, aiming at summarizing the current knowledge on cardiovascular implications of NTDs and providing diagnostic as well as management recommendations which can be tailored to low-resource settings. The diagnostic and management algorithms of 13 unique NTDs are presented and summarized.

EXPERT OPINION

Recognizing cardiac manifestations of NTDs can significantly alter disease trajectory and all physicians benefit from improved knowledge about NTDs. Great potential exists to advance patient care by improving data collection, communication, and international collaboration.

Identification of Trichinella taxa by ITS-1 amplicon next-generation sequencing with an improved resolution for detecting underrepresented genotypes in mixed natural infections

BACKGROUND

Amplicon-based next-generation sequencing (NGS) has rapidly gained popularity as a powerful method for delineating taxa in complex communities, including helminths. Here, we applied this approach to identify species and genotypes of zoonotic nematodes of the Trichinella genus. A known limitation of the current multiplex PCR (mPCR) assay recommended by the International Commission on Trichinellosis is that it does not differentiate Trichinella nativa from T. chanchalensis.

METHODS

The new assay entails deep sequencing of an amplified variable fragment of the ribosomal cistron's (rDNA) internal transcribed spacer 1 using the Illumina platform. The assay was evaluated using first-stage larvae (L1) of select laboratory strains of various Trichinella taxa mixed in known proportions and then validated using archived L1 from 109 wildlife hosts. The species/genotypes of these L1 isolates from wildlife were previously determined using mPCR.

RESULTS

NGS data analysis for Trichinella laboratory strains selected as representative of North American fauna revealed a sequence representation bias. Trichinella pseudospiralis, a non-encapsulated species, was the most underrepresented when mixed with T. spiralis, T. murrelli, T. nativa and Trichinella T6 in equal quantities. However, five L1 of T. pseudospiralis were readily revealed by NGS in a mix with 2000 L1 of T. nativa (1:400 ratio). From naturally infected wildlife, all Trichinella taxa revealed by mPCR were also identified by NGS in 103 of 107 (96.3%) samples amplified on both assays. NGS identified additional taxa in 11 (10.3%) samples, whereas additional taxa were revealed by mPCR in only four (3.7%) samples. Most isolates comprised single or mixed infections of T. nativa and Trichinella T6. On NGS, T. chanchalensis (T13) was detected in combination with Trichinella T6 in a wolverine (Gulo gulo) and in combination with T. nativa and Trichinella T6 in a marten (Martes americana) from the Northwest Territories, Canada.

CONCLUSIONS

This new NGS assay demonstrates strong potential as a single assay for identifying all recognised Trichinella taxa as well as improved sensitivity for detecting under-represented and novel genotypes in mixed infections. In addition, we report a new host record for T. chanchalensis in American marten.

Impact of atorvastatin and mesenchymal stem cells combined with ivermectin on murine trichinellosis

Trichinellosis is one of the global food-borne parasitic diseases that can cause severe tissue damage. The traditionally used drugs for the treatment of trichinellosis have limited efficacy against the encysted larvae in the muscular phase of the disease. Therefore, this study aimed to evaluate the role of atorvastatin and mesenchymal stem cells combined with ivermectin against different phases of Trichinella in experimentally infected mice. A total of 120 male Swiss albino mice were divided into two major groups (n = 60 of each), intestinal and muscular phases. Then, each group was subdivided into 10 subgroups (n = 6); non-infected control, infected non-treated control, infected ivermectin treated, infected atorvastatin treated, infected mesenchymal stem cells treated, infected combined ivermectin and atorvastatin treated, infected combined mesenchymal stem cells and ivermectin treated, infected combined mesenchymal stem cells and atorvastatin treated, infected combined mesenchymal stem cells and a full dose of (ivermectin and atorvastatin) treated, and infected combined mesenchymal stem cells and half dose of (ivermectin and atorvastatin) treated. Mice were sacrificed at days 5 and 35 post-infection for the intestinal and muscular phases, respectively. The assessment was performed through many parameters, including counting the adult intestinal worms and muscular encysted larvae, besides histopathological examination of the underlying tissues. Moreover, a biochemical assay for the inflammatory and oxidative stress marker levels was conducted. In addition, levels of immunohistochemical CD31 and VEGF gene expression as markers of angiogenesis during the muscular phase were investigated. The combined mesenchymal stem cells and atorvastatin added to ivermectin showed the highest significant reduction in adult worms and encysted larvae counts, the most noticeable improvement of the histopathological changes, the most potent anti-inflammatory (lowest level of IL-17) and anti-angiogenic (lowest expression of CD31 and VEGF) activities, and also revealed the highly effective one to relieve the oxidative stress (lowest level of SOD, GSH, and lipid peroxidase enzymes). These observed outcomes indicate that adding mesenchymal stem cells and atorvastatin to ivermectin synergistically potentiates its therapeutic efficacy and provides a promising candidate against trichinellosis.

A Large-Scale Outbreak of Trichinellosis from Infected Wild Boar Meat in Croatia and the Role of Real-Time PCR Assays in Confirming the Source of the Disease

BACKGROUND

Trichinellosis in Croatia posed a significant health concern during the 1990s, followed by a notable improvement in the epidemiological situation. However, in 2017, there was a resurgence, with 37 recorded cases in 3 outbreaks and 3 sporadic cases. The source of this epidemic was homemade meat products derived from wild boar meat, leading to 26 infections.

METHODS

At the beginning of the outbreak and during the treatment of the patients, the medical and epidemiological records prepared throughout the investigation and over the course of patient treatment were reviewed. The recovery of the first-stage (L1) larvae from suspect meat products was achieved by artificial digestion. The molecular identification of the isolated larvae was performed by multiplex PCR. The molecular identification of the meat used to prepare the meat products was performed by real-time PCR assays.

RESULTS

The epidemic started in early 2017. In total, 71 exposed persons were documented: 26 with clinical symptoms and 3 hospitalised in two cities in different counties. The L1 burden in three different meat products was from 5.25 to 7.08 larvae per gram (LPG), and T. spiralis was determined as the aetiological agent of the outbreak. The molecular and biological identification confirmed that implicated meat products were made solely from wild boar meat.

CONCLUSIONS

Although trichinellosis is no longer a frequent occurrence in Croatia, several cases are still registered nearly every year. Wild boar meat poses an important risk factor for human health if compulsory testing is not conducted before consumption, especially if the meat products are consumed without proper thermal processing.

Metabolite profiling of Trichinella spiralis adult worms and muscle larvae identifies their excretory and secretory products

Human trichinellosis is a parasitic infection caused by roundworms belonging to the genus Trichinella, especially Trichinella spiralis. Early and accurate clinical diagnoses of trichinellosis are required for efficacious prognosis and treatment. Current drug therapies are limited by antiparasitic resistance, poor absorption, and an inability to kill the encapsulating muscle-stage larvae. Therefore, reliable biomarkers and drug targets for novel diagnostic approaches and anthelmintic drugs are required. In this study, metabolite profiles of T. spiralis adult worms and muscle larvae were obtained using mass spectrometry-based metabolomics. In addition, metabolite-based biomarkers of T. spiralis excretory-secretory products and their related metabolic pathways were characterized. The metabolic profiling identified major, related metabolic pathways involving adenosine monophosphate (AMP)-dependent synthetase/ligase and glycolysis/gluconeogenesis in T. spiralis adult worms and muscle larvae, respectively. These pathways are potential drug targets for the treatment of the intestinal and muscular phases of infection. The metabolome of larva excretory-secretory products was characterized, with amino acid permease and carbohydrate kinase being identified as key metabolic pathways. Among six metabolites, decanoyl-l-carnitine and 2,3-dinor-6-keto prostaglandin F1α-d9 were identified as potential metabolite-based biomarkers that might be related to the host inflammatory processes. In summary, this study compared the relationships between the metabolic profiles of two T. spiralis growth stages. Importantly, the main metabolites and metabolic pathways identified may aid the development of novel clinical diagnostics and therapeutics for human trichinellosis and other related helminthic infections.

The impact of β-glucan on the therapeutic outcome of experimental Trichinella spiralis infection

Trichinellosis is a cosmopolitan zoonosis that is caused mainly by Trichinella spiralis infection. The human disease ranges from mild to severe and fatality may occur. The treatment of trichinellosis still presents a challenge for physicians. Anti-inflammatory drugs are usually added to antiparasitic agents to alleviate untoward immuno-inflammatory responses and possible tissue damage but they are not without adverse effects. Thus, there is a need for the discovery of safe and effective compounds with anti-inflammatory properties. This study aimed to evaluate the activity of β-glucan during enteral and muscular phases of experimental T. spiralis infection as well as its therapeutic potential as an adjuvant to albendazole in treating trichinellosis. For this aim, mice were infected with T. spiralis and divided into the following groups: early and late β-glucan treatment, albendazole treatment, and combined treatment groups. Infected mice were subjected to assessment of parasite burden, immunological markers, and histopathological changes in the small intestines and muscles. Immunohistochemical evaluation of NF-κB expression in small intestinal and muscle tissues was carried out in order to investigate the mechanism of action of β-glucan. Interestingly, β-glucan potentiated the efficacy of albendazole as noted by the significant reduction of counts of muscle larvae. The inflammatory responses in the small intestine and skeletal muscles were mitigated with some characteristic qualitative changes. β-glucan also increased the expression of NF-κB in tissues which may account for some of its effects. In conclusion, β-glucan showed a multifaceted beneficial impact on the therapeutic outcome of Trichinella infection and can be regarded as a promising adjuvant in the treatment of trichinellosis.

A Quality Assurance Discrimination Tool for the Evaluation of Satellite Laboratory Practice Excellence in the Context of the European Official Meat Inspection for Trichinella spp

Trichinellosis is a parasitic foodborne zoonotic disease transmitted by ingestion of raw or undercooked meat containing the first larval stage (L1) of the nematode. To ensure the quality and safety of food intended for human consumption, meat inspection for detection of Trichinella spp. larvae is a mandatory procedure according to EU regulations. The implementation of quality assurance practices in laboratories that are responsible for Trichinella spp. detection is essential given that the detection of this parasite is still a pivotal threat to public health, and it is included in list A of Annex I, Directive 2003/99/EC, which determines the agents to be monitored on a mandatory basis. A Quality Management System (QMS) was applied to slaughterhouses and game handling establishments conducting Trichinella spp. testing without official accreditation but under the supervision of the relevant authority. This study aims to retrospectively analyze the outcomes of implementing the QMS in slaughterhouses and game handling establishments involved in Trichinella testing in southern Spain. Canonical discriminant analyses (CDAs) were performed to design a tool enabling the classification of SLs while determining whether linear combinations of measures of quality-assurance-related traits describe within- and between-SL clustering patterns. The participation of two or more auditors improves the homogeneity of the results deriving from audits. However, when training expertise ensures that such levels of inter-/intralaboratory homogeneity are reached, auditors can perform single audits and act as potential trainers for other auditors. Additionally, technical procedure issues were the primary risk factors identified during audits, which suggests that they should be considered a critical control point within the QMS.

Acetazolamide loaded-silver nanoparticles: A potential treatment for murine trichinellosis

Trichinellosis is a global food-borne disease caused by viviparous parasitic nematodes of the genus Trichinella. Due to the lack of effective, safe therapy and the documented adverse effects of traditional therapy, this study aimed to evaluate the therapeutic effect of acetazolamide-loaded silver nanoparticles (AgNPs) on murine trichinellosis. Fifty male Swiss albino mice were divided into five groups of ten mice each: Group I, normal control group; Group II, infected with T. spiralis and not treated; Group III, infected and given AgNPs; Group IV, infected and treated with acetazolamide; and Group V, infected and treated with acetazolamide-loaded AgNPs. Mice were infected orally with 250 larvae. The efficacy was assessed by counting T. spiralis adults and larvae, measuring serum total antioxidant capacity, and observing the histopathological and ultrastructural alterations. Acetazolamide-loaded AgNPs treatment exhibited the highest percentage of reduction (84.72% and 80.74%) for the intestinal adults and the muscular larvae of T. spiralis-infected animals, respectively. Furthermore, during the intestinal and muscular phases, the serum of the same group had the best free-radical scavenging capacity (antioxidant capacity), which reduced tissue damage induced by oxidative stress. Histopathologically, the normal intestinal and muscular architecture was restored in the group treated with acetazolamide-loaded AgNPs, in addition to the reduced inflammatory infiltrate that alleviated inflammation compared to infected animals. Our results confirmed the marked destruction of the ultrastructural features of T. spiralis adults and larvae. Acetazolamide-loaded AgNPs are a promising therapy against T. spiralis infection.

The Effects of Honeysuckle (Lonicera caerulea L.) Berry Iridoid-Anthocyanin Extract on the Intestinal and Muscle Histopathology in Mice during Experimental Trichinellosis

The aim of the study was to determine the effect of iridoid-anthocyanin extract from honeysuckle (Lonicera caerulea L.) (LC) berries on histopathological changes in the intestines and muscles during experimental trichinellosis in mice. The LC extract was administered to uninfected mice (LC group) and Trichinella-spiralis-infected mice (T+LC) orally at a dose of 2 g/kg bw, six times at 24 h intervals, from day 3 prior to infection to day 3 post-infection (dpi). Jejunum samples were collected on 5, 7, 14, and 21 dpi, and their histological assessment involved the villus height to crypt depth ratio (VH/CD), goblet cell (GC) number, and morphological changes. In the T. spiralis-infected muscles, the extent of inflammatory infiltration on the 14th and 21st dpi was assessed. LC in the infected mice restored the VH/CD ratio to control values on 14 dpi. A beneficial effect of the LC extract on the villus height was also observed 14 dpi in the LC and T+LC groups. No differences in the extent of inflammatory infiltration in the muscles between the T+LC and T groups were observed. In conclusion, the iridoid-anthocyanin extract from honeysuckle berry contributed to alleviating the symptoms of the intestinal phase of T. spiralis infection.

The impact of MIF deficiency on alterations of fecal microbiota in C57BL/6 mice induced by Trichinella spiralis infection

Trichinellosis caused by Trichinella spiralis (T. spiralis) is a major food-borne parasitic zoonosis worldwide. Prevention of trichinellosis is an effective strategy to improve patient quality of life. Macrophage migration inhibitory factor (MIF) is closely related to the occurrence and development of several parasitic diseases. Studying the impact of MIF deficiency (Mif-/- ) on the alterations in host fecal microbiota due to T. spiralis infection may contribute to proposing a novel dual therapeutic approach for trichinellosis. To reveal the diversity and differences in fecal microbial composition, feces were collected from T. spiralis-uninfected and T. spiralis-infected wild-type (WT) and MIF knockout (KO) C57BL/6 mice at 0, 7, 14, and 35 days post-infection (dpi), and the samples were sent for 16S rRNA amplicon sequencing on the Illumina NovaSeq platform. Flow cytometry was used to determine the expression levels of IFN-γ and IL-4 in the CD4+ /CD8+  T-cell sets of mouse spleens. The results showed that operational taxonomic unit (OTU) clustering, relative abundance of microbial composition, alpha diversity, and beta diversity exhibited significant changes among the eight groups. The LEfSe analysis selected several potential biomarkers at the genus or species level, including Akkermansia muciniphila, Lactobacillus murinus, Coprococcus catus, Firmicutes bacterium M10_2, Parabacteroides sp. CT06, and Bacteroides between the KTs and WTs groups. The predicted bacterial functions of the fecal microbiota were mainly involved in metabolism, such as the metabolism of carbohydrates, amino acids, energy, cofactors, vitamins, nucleotides, glycans, and lipids. Flow cytometry revealed an increased CD3+ CD8- /CD3+ CD8+  T-cell ratio and increased IFN-γ and IL-4 levels in CD3+ CD8- T-cell sets from WT and MIF KO mice at 7 dpi. The results indicated that both MIF KO and infection time have a significant influence on the CD3+ CD8- IFN-γ+ and CD3+ CD8- IL-4+ response in mice after T. spiralis. In conclusion, this research showed alterations of the fecal microbiota and immune response in both WT and MIF KO mice before and after T. spiralis infection. These results revealed a potential role of MIF in regulating the pathogenesis of trichinellosis related to the intestinal microbiota. Importantly, the selected potential biomarkers combined with MIF will also offer a novel therapeutic approach to treat trichinellosis in the future.

Genetic identification of Trichinella species found in wild carnivores from the territory of Kazakhstan

Trichinellosis, also called trichinosis, is a foodborne parasitic disease caused by eating raw or undercooked meat from animals infected with Trichinella spp. larvae and affects both animals and humans. Although on the territory of Kazakhstan, the species characteristics and prevalence of this helminth were studied back in the 90s, the data have not been updated since then. Given the above, our study was aimed at identifying Trichinella spp. using parasitological and molecular genetics methods. In our work, we studied 160 samples of muscle tissue of wild animals living in the natural zones of steppes and semi-deserts. Of the animals examined, 32 were positive for Trichinella spp., including 1 lynx (Lynx lynx), 17 wolves (Canis lupus), 11 foxes (Vulpes vulpes), 1 jackal (Canis aureus) and 2 corsac foxes (Vulpes corsac). Helminths were extracted using the digestion method. DNA was extracted using a Gene Jet commercial kit (Thermo Fisher Scientific, United Kingdom). For species identification a multiplex PCR, amplification of ESV, ITS1, and ITS2 genes regions was performed. After that, uniplex PCR was performed on the 5S rDNA and ITS1 genes region for sequencing analysis. The resulting sequences were subsequently used to construct a phylogenetic tree and the studied samples were identified as Trichinella nativa and Trichinella britovi. Thus, we can conclude that there is a circulation of two species of Trichinella in Kazakhstan, highlighting that constant control and monitoring of wild animals are necessary to prevent transmission and protect the health of people.

Trichinellosis dissemination among wild carnivores in the Republic of Kazakhstan: A 10-year study

Background and Aim

Trichinellosis is caused by a species of roundworm called Trichinella and is an invasive disease causing severe medical, veterinary, and socioeconomic problems worldwide. More than 100 mammalian species are Trichinella hosts. Among domestic animals, pigs and dogs are prone to trichinellosis. An essential aspect of controlling the spread of infection is to identify the number and level of infections in wild carnivores in the country. However, the number, habitats, and movements of wild animal Trichinella hosts in Kazakhstan have not been reported yet. This study aimed to monitor the wild animal habitat nearby the settlements for tracking the trichinellosis speading among carnivores.

Materials and Methods

Wild carnivorous animals were captured in seven regions of the Republic of Kazakhstan. The carcasses of corsacs, wolves, foxes, wild boars, and badgers were studied. Muscle tissue samples from spontaneously infected wild animals were collected. The digestion method in "GASTROS-2M" was used to isolate Trichinella spp. from animal muscles. The species of the parasite was determined by a polymerase chain reaction for 5S spacer of Trichinella ribosomal DNA with subsequent sequencing by Senger. Statistical analysis methods were performed for average value in Microsoft Excel 2010.

Results

The results of the research showed that among 155 animals wolves (20.4%) and foxes (26.7%) were the most infected with invasive Trichinella larvae. The invasion intensity was 503.6% in foxes and 289.7% in wolves. However, badgers (164%), wild boars (0%), and corsacs (0%) presented lower invasion levels. Using specific primers, larvae samples were identified as Trichinella nativa.

Conclusion

The results of monitoring revealed the spread of trichinosis among wild animals: wolves, foxes, badgers. The Karaganda, Kostanay, Western Kazakhstan, and Akmola regions had the largest distribution of wild animals infected with trichinellosis. In total, 20% of the 155 studied animals were infected. The greatest invasion intensity was typical for wolves, foxes and badgers. It is necessary to monitor the spread of trichinellosis among wild carnivores to control the epidemiological situation and reduce the level of spontaneous infection among animals. Regular monitoring of habitats and carnivores must be conducted within the country and in the border areas.

Immunomodulatory in vitro effects of Trichinella cystatin-like protein on mouse splenocytes

Trichinella parasites have developed specific mechanisms allowing successful completion of their life cycle. These mechanisms are in a great part involved in immunomodulation and studying them may provide a valuable insight into the functioning of the immune system. Trichinella products may be also used as potential therapeutic agents to treat immune diseases. This study investigates the immunomodulatory potential of recombinant multi cystatin-like protein (CLP) derived from T. britovi to determine whether CLP has anti-inflammatory properties in vitro. CLP is a highly antigenic glycoprotein present in Trichinella excetory-secretory (ES) products. AlphaFold structure prediction confirms that it consists of three type-two cystatin-like domains. Mouse splenocytes were stimulated in vitro with lipopolysaccharide (LPS) and co-stimulated with recombinant CLP. The culture supernatants were collected and tested for secreted cytokine levels using ELISA. CLP was found to reduce LPS-induced secretion of inflammatory cytokines TNFα and IL-6. On the contrary, in some experimental groups, co-stimulation with CLP resulted in increased secretion of the regulatory cytokine IL-10. The obtained results indicate that CLP has anti-inflammatory properties and future research on its function is advisable, specifically in the context of the therapy of inflammatory disorders.

Extract of Torreya nucifera Pericarps Exhibits a Parasiticidal Effect on the Nematode Parasite, Trichinella spiralis

Benzimidazole derivatives can effectively treat nematode parasitic infections; however, some derivatives demand distinct administrative strategies depending on plasma concentration and patient conditions. Numerous studies have examined the potential of natural extracts to exert parasiticidal activity with minimal side effects. Herein, we examined the potential parasiticidal effects of Torreya nucifera extract. The pericarps of T. nucifera were extracted with methanol, dried, and the pellet was dissolved in hot water (Tn-Phw). We designed four individual mouse experiments to clarify the prophylactic and therapeutic effects of Tn-Phw on Trichinella spiralis infection. Also, 100 L1 larvae were isolated and treated with Tn-Phw (10 mg/mL) in vitro to confirm the killing effect. Furthermore, we microscopically examined the morphology of L1 larvae to confirm the parasite-killing effect and analyzed the morphology using a scanning electron microscope (SEM). The expression of three molting-related genes was confirmed to determine whether Tn-Phw induced morphological changes in L1 larvae. Following treatment with Tn-Phw, L1 larvae death was observed after 16 h. Following SEM examination, the healthy muscle larvae showed striated ridges and wrinkles; this was not observed in extract-treated muscle larvae. Expression levels of the three molting-related genes did not differ between the Tn-Phw-treated and control groups. T. spiralis-infected mice pretreated with Tn-Phw showed significantly reduced muscle larva infection when compared with control mice. In all experiments, treatment with Tn-Phw afforded preventive and therapeutic effects against T. spiralis infection and parasitism. Natural substances against nematode parasites could be developed as therapeutic agents with few side effects and enhanced parasiticidal efficacy.

Inhibition of Trichinella spiralis Membrane-Associated Progesterone Receptor (MAPR) Results in a Reduction in Worm Burden

Trichinella spiralis (T. spiralis), a nematode parasite, is the major cause of Trichinellosis, a zoonotic disease. A key role of MAPR in the reproductive system is to maintain pregnancy. Previous studies found that antihormone drug design and vaccine therapy of recombinant protein (rTs-MAPRC2) control T. spiralis infection. The current study investigates the inhibitory effects of different ratios of antibodies against Ts-MAPRC2 on the development of muscle larvae (ML) and newborn larvae (NBL). First, we performed indirect immunofluorescence assays and examined the effects of rTs-MAPRC2-Ab on ML and NBL in vitro as well as in vivo. Afterward, siRNA-Ts-MAPRC2 was transfected into T. spiralis muscle larvae. Following that, Ts-MAPRC2 protein was detected by Western Blotting, and mRNA levels were determined by qPCR. We also assessed whether siRNA-treated NBLs were infective by analyzing muscle larvae burden (MLs). Our results showed that rTs-MAPRC2-Ab greatly inhibited the activity of the Ts-MAPRC2 in ML and NBL of T. spiralis and rTs-MAPRC2-Ab reduced larval infectivity and survival in the host in a dose-dependent manner (1:50, 1:200, 1:800 dilutions). Furthermore, siRNA-Ts-MAPRC2 effectively silenced the Ts-MAPRC2 gene in muscle larvae (ML) in vitro, as well as in newborn larvae (NBL) of T. spiralis in vivo. In addition, siRNA-Ts-MAPRC2 (siRNA180, siRNA419, siRNA559) reduced host larval survival and infectivity significantly. This study, therefore, suggests that Ts-MAPRC2 might be a novel molecular target useful in the development of vaccines against T. spiralis infection.

Niosome as an Effective Nanoscale Solution for the Treatment of Microbial Infections

Numerous disorders go untreated owing to a lack of a suitable drug delivery technology or an appropriate therapeutic moiety, particularly when toxicities and side effects are a major concern. Treatment options for microbiological infections are not fulfilled owing to significant adverse effects or extended therapeutic options. Advanced therapy options, such as active targeting, may be preferable to traditional ways of treating infectious diseases. Niosomes can be defined as microscopic lamellar molecules formed by a mixture of cholesterol, nonionic surfactants (alkyl or dialkyl polyglycerol ethers), and sometimes charge-inducing agents. These molecules comprise both hydrophilic and hydrophobic moieties of varying solubilities. In this review, several pathogenic microbes such as Staphylococcus aureus, Pseudomonas aeruginosa, Klebsiella pneumoniae, Plasmodium, Leishmania, and Candida spp. have been evaluated. Also, the development of a proper niosomal formulation for the required application was discussed. This review also reviews that an optimal formulation is dependent on several aspects, including the choice of nonionic surfactant, fabrication process, and fabrication parameters. Finally, this review will give information on the effectiveness of niosomes in treating acute microbial infections, the mechanism of action of niosomes in combating microbial pathogens, and the advantages of using niosomes over other treatment modalities.

Real-time PCR versus traditional and Nano-based ELISA in early detection of murine trichinellosis

Trichinellosis is a serious foodborne zoonosis. It poses a serious risk to public health worldwide. Early serological diagnosis of trichinellosis is influenced by an immunological 'silent' phase following infection. This highlights the necessity for developing sensitive diagnostic approaches to be employed when antibodies cannot be detected. In this work, the validity of traditional ELISA, Nano-ELISA and real time polymerase chain reaction (PCR) were evaluated in early diagnosis of Trichinella spiralis. Swiss albino mice were orally infected with 100 and 300 muscle larvae/mouse. Mice were sacrificed 4, 6, 8, 10, 15, and 28 days post-infection (dpi). Blood samples were tested for circulating antigen by traditional ELISA and Nano-ELISA using anti-rabbit polyclonal IgG conjugated with AgNPs and for Rep gene by SYBR green real-time PCR. Rep gene detection by SYBR green real-time PCR could detect T. spiralis with 100% sensitivity in the mild infection group at 8 dpi, while in the severe infection group it reached 100% sensitivity at 4 dpi. Nano-ELISA could detect T. spiralis circulating antigen from 4 dpi in both mild and severe infection and reached 100% sensitivity at 8 dpi and 6 dpi in mild and severe infection, respectively. However, traditional ELISA could detect T. spiralis circulating antigen from 6 dpi and reached maximum sensitivity at 15 dpi in the mild infection group, while in the severe infection group detection began at 4 dpi and reached 100% sensitivity at 8 dpi. Nano-ELISA and real time PCR, using Rep gene, are useful tools for the detection of early T. spiralis infection even in its mild infection state.

The Landscape of Parasitic Infections in the United States

The landscape of parasitic infections in the United States has shifted dramatically over the past century. Although infections such as malaria have been successfully eliminated, others remain endemic and pose a significant public health risk. Numerous parasitic infections are also imported each year. This article focuses on endemic parasitic infections that may be commonly seen in anatomical pathology preparations and discusses their biology, diagnostic histopathological features, and epidemiology.

Antihelminthic and antiangiogenic effects of zinc oxide nanoparticles on intestinal and muscular phases of trichinellosis

Trichinellosis is a worldwide zoonotic disease affecting a wide range of mammals, including humans. It has intestinal and muscular phases. The current work was done to experimentally evaluate the efficacy of zinc oxide nanoparticles (ZnO NPs) and their combination with albendazole on intestinal and muscular stages of Trichinella spiralis (T. spiralis) infection. We had five main groups of mice: Group 1, non-infected control; Group 2, infected control; Group 3, infected and treated with albendazole; Group 4, infected and treated with ZnO NPs; and Group 5, infected and treated with albendazole and ZnO NPs. Each group was divided into two subgroups (A for the intestinal phase and B for the muscular phase). Drug effects were evaluated by parasitological, histopathological, and biochemical studies, including oxidant/antioxidant analysis and vascular endothelial growth factor (VEGF) gene expression in muscle tissue by quantitative real-time PCR. ZnO NPs resulted in a significant reduction of both intestinal and muscular phases of T. spiralis. Their combination with albendazole resulted in the complete eradication of adult worms and the maximum reduction of larval deposition in muscle tissue. Additionally, the treatment showed improvement in T. spiralis-induced pathological changes and oxidative stress status. Moreover, a significant decrease in VEGF gene expression was detected in the treated groups when compared with the infected control. In conclusion, ZnO NPs presented an antihelminthic effect against both adult and larval stages of T. spiralis. In addition, it enhanced antioxidant status and suppressed angiogenesis in muscle.

Repurposing drugs to treat trichinellosis: in vitro analysis of the anthelmintic activity of nifedipine and Chrysanthemum coronarium extract

Albendazole is the most common benzimidazole derivative used for trichinellosis treatment but has many drawbacks. The quest for alternative compounds is, therefore, a target for researchers. This work aims to assess the in vitro anthelmintic effect of nifedipine, a calcium channel blocker, and a methanol extract of the flowers of Chrysanthemum coronarium as therapeutic repurposed drugs for treating different developmental stages of Trichinella spiralis in comparison with the reference drug, albendazole. Adult worms and muscle larvae of Trichinella spiralis were incubated with different concentrations of the studied drugs. Drug effects were evaluated by parasitological and electron microscopic examination.As a result, the effects of these drugs on muscle larvae were time and dose-dependent. Moreover, the LC₅₀ after 48 h incubation was 81.25 µg/ml for albendazole, 1.24 µg/ml for nifedipine, and 229.48 µg/ml for C. coronarium. Also, the effects of the tested drugs were prominent on adult worms as the LC₅₀ was 89.77 µg/ml for albendazole, 1.87 µg/ml for nifedipine, and 124.66 µg/ml for C. coronarium. SEM examination of the tegument of T. spiralis adult worms and larvae showed destruction of the adult worms' tegument in all treated groups. The tegument morphological changes were in the form of marked swellings or whole body collapse with the disappearance of internal contents. Furthermore, in silico studies showed that nifedipine might act as a T. spiralis β-tubulin polymerization inhibitor.Our results suggest that nifedipine and C. coronarium extract may be useful therapeutic agents for treating trichinellosis and warrant further assessment in animal disease models.

Trichinella proficiency testing in Southeastern European countries

In some Southeastern European (SEE) countries, like Serbia, Romania, and Bulgaria, trichinellosis is one of the most important foodborne zoonotic diseases. In those countries, EU regulation and local authorities require the staff of laboratories performing official controls on meat to be properly trained and to check their competence by participating regularly in proficiency testing (PT). PTs are organized by National Reference Laboratories for Trichinella of each country and involve all official laboratories testing meat. In Romania and Bulgaria, the organization of PT for the detection of Trichinella larvae in meat by Magnetic Stirrer Method (MSM) started in 2012. In Croatia and Serbia PT was first organized in 2015 and 2017, respectively. This study presents data on the performance obtained by official laboratories of SEE countries that organize PT at national level and compares the performance obtained by laboratories belonging to different countries. Results suggest that the constant participation in PT leads to an increase in the performance of participating laboratories by positively affecting the staff accuracy in sample testing by MSM. Since the percentage of recovered larvae was in some cases suboptimal (<80%) and occasionally very poor (<40%), there is room for improvement. The regular participation in PT by laboratories involved in official controls on meat intended for human consumption is fundamental to guarantee consumer safety.

Fused Triazinobenzimidazoles Bearing Heterocyclic Moiety: Synthesis, Structure Investigations, and In Silico and In Vitro Biological Activity

[1,3,5]Triazino[1,2-a]benzimidazole-2-amines bearing heterocyclic moiety in 4-position were synthesized. The compounds were characterized by elemental analysis, IR, ¹H-NMR, ¹³C-NMR, and HRMS spectroscopy. The molecular geometry and electron structure of these molecules were theoretically studied using density functional theory (DFT) methods. The molecular structure of the synthesized fused triazinobenzimidazole was confirmed to correspond to the 3,4-dihydrotriazinobenzimidazole structure through the analysis of spectroscopic NMR data and DFT calculations. The antinematodic activity was evaluated in vitro on isolated encapsulated muscle larvae (ML) of Trichinella spiralis. The results showed that the tested triazinobenzimidazoles exhibit significantly higher efficiency than the conventional drug used to treat trichinosis, albendazole, at a concentration of 50 μg/mL. The compound 3c substituted with a thiophen-2-yl moiety exhibited the highest anthelmintic activity, with a larvicidal effect of 58.41% at a concentration of 50 μg/mL after 24 h of incubation. Following closely behind, the pyrrole analog 3f demonstrated 49.90% effectiveness at the same concentration. The preliminary structure-anti-T. spiralis activity relationship (SAR) of the analogues in the series was discussed. The cytotoxicity of the benzimidazole derivatives against two normal fibroblast cells (3T3 and CCL-1) and two cancer human cell lines (MCF-7 breast cancer cells and chronic myeloid leukemia cells AR-230) was evaluated using the MTT-dye reduction assay. The screening results indicated that the compounds showed no cytotoxicity against the tested cell lines. An in silico study of the physicochemical and pharmacokinetic characteristics of the novel synthesized fused triazinobenzimidazoles showed that they were characterized by a significant degree of drug-likeness and optimal properties for anthelmintic agents.

In vitro knockdown of TsDNase II-7 suppresses Trichinella spiralis invasion into the host's intestinal epithelial cells

Trichinella spiralis (T. spiralis) adult-specific deoxyribonuclease II-7 (TsDNase II-7), a member of the DNase II-like nuclease family with no DNase II activity, was identified in the excretory-secretory (ES) products of adult worms (AWs). However, its biological functions are still unclear. Our previous study revealed that TsDNase II-7 is located around the infection site in the intestinal tissue, speculating that it was involved in the T. spiralis invasion of host intestinal epithelial cells (IECs). This study aimed to use RNA interference to verify our speculation that TsDNase II-7 in 3-day old adult T. spiralis (Ad3) plays a role in intestinal invasion. TsDNase II-7-specific small interfering RNAs (siRNAs) were delivered into muscle larvae (MLs) to knockdown TsDNase II-7 expression by electroporation. Twenty-four hours later, the MLs transfected with 2 μM siRNA-841 exhibited decreased in TsDNase II-7 transcription and expression as compared to the control MLs. The knockdown of TsDNase II-7 expression did not affect ML viability, and the low expression of TsDNase II-7 still maintained in Ad3 recovered from TsDNase II-7-RNAi-ML infected mice, resulting in a weakened ability of Ad3 to invade intestinal epithelial cells (IECs). These results indicated that knockdown of TsDNase II-7 gene expression via RNA interference (RNAi) suppressed adult worm invasion and confirmed that TsDNase II-7 plays a crucial role during the intestinal phase of T. spiralis infections, which provided new candidate for vaccine development of T. spiralis.

Vitamin D3 supplementation could ameliorate the inflammatory and redox status in the muscular phase of trichinellosis

Nutritional supplements, particularly vitamin D, have been widely used worldwide in the treatment of various infections, including parasites. This study aimed to evaluate the potential effects of vitamin D3 supplementation on the muscular phase of trichinellosis in experimental animals. Mice were divided as follows: (group I): infected untreated, (group IIa) infected and treated with vitamin D3 for 12 doses beginning 2 weeks before infection and continuing after infection, (group IIb) infected and treated with vitamin D3 for 8 doses beginning on the same day of infection, (group III) normal control, (group IVa) which received vitamin D3 for 12 doses and (group IVb) which received vitamin D3 for 8 doses. Mice were sacrificed 35 days after infection and total muscle larval count, and histopathological examination of muscle samples with immunohistochemical staining of cyclooxygenase 2 (COX2) and inducible nitric oxide synthase (iNOS) were performed. Muscle relative cathelicidin mRNA expression was assessed, as well as serum levels of muscle enzymes CK and LDH, interleukin-4 (IL-4), IL-10, IL-17 and interferon-gamma (INF-γ). Vitamin D3 supplementation significantly reduced muscle larval count, inflammatory cellular infiltration, COX2 and iNOS expression. Furthermore, it increased cathelicidin gene expression, decreased serum levels of CK and LDH and affected serum cytokine levels, increasing serum IL-4 and IL10 levels while decreasing serum INF γ and IL-17. In conclusion, vitamin D3 supplementation has favorable outcomes on the muscle phase of trichinellosis, including anti-inflammatory, antioxidant, and immunomodulatory effects.

Trichinellosis in Hospitalized Children and Adults from Western Romania: A 11-Year Retrospective Study

Trichinellosis, a serious and sometimes fatal human disease, is a consequence of consuming raw or improperly cooked meat containing the infective larvae of Trichinella spp. The aim of this observational cohort retrospective study is to compare the epidemiological, laboratory, clinical and therapeutic aspects of trichinellosis in children and adults from Western Romania. We investigated the medical records of patients who were diagnosed with trichinellosis and hospitalized between 17 January 2010 and 31 December 2020. One hundred thirty-three patients were identified according to the electronic databases of infectious disease hospitals, located in four counties from Western Romania. A total of 19 patients (14.28%) were children and 114 patients (85.71%) were adults. In children, the most frequent symptoms were digestive in 78.94%, followed by fever in 57.89%, eyelid or facial edema in 57.89% and myalgia in 52.63% of cases, while adults presented mainly myalgia in 87.71%, followed by fever in 77.19%, digestive symptoms in 68.42% and eyelid or facial edema in 66.66% of cases. The source of infection was pork meat products in the majority of patients (89.47%). Our results revealed a general declining trend in infection rates for both children and adults during the studied period. The vast majority of cases were severe and all required hospitalization. Education of the population along with public health strategies should be improved and maintained to fully prevent trichinellosis in Western Romania.

Scheme of Effective Epidemiological Investigations in Trichinella Outbreaks on Pig Farms

Trichinellosis is a parasitic, zoonotic disease caused by larvae of the genus Trichinella. Infection occurs via the consumption of raw or undercooked meat containing this parasite. Symptoms of the disease manifest as intestinal disorders, followed by facial swelling, fever, muscle pain and other symptoms, eventually leading to neurological and cardiac complications and even death. In Europe, trichinellosis is most often associated with the consumption of meat from wild boars, pigs and horses. In recent years, wild boars that are hunted illegally and not tested for Trichinella spp. have been the most common cause of trichinellosis in humans; however, there have also been cases where infected pigs have been the source of infection. When trichinellosis is suspected in humans, epidemiological measures are taken to identify the source. Similarly, an epidemiological investigation should be initiated whenever Trichinella spp. has been detected in pigs. However, commonly used actions do not provide sufficient data to determine the source of infection for pigs and to prevent further transmission. Therefore, in this article, we propose a scheme for effective epidemiological investigations into Trichinella outbreaks on pig farms that can help trace the transmission mechanisms of the parasite and that takes into account currently available testing tools. The proposed pathway can be easily adopted for epidemiological investigations in routine veterinary inspection work.

Establishment of a method for detecting Trichinella spiralis in ovine muscle tissues using real-time fluorescence quantitative PCR

Trichinellosis is caused by Trichinella spiralis, a meat-borne zoonotic disease transmitted to humans through the consumption of infected undercooked or raw meat. Surveillance using safe and precise diagnostic tools to diagnose T. spiralis in sheep is needed to assess the incidence and probability of transmission from sheep to humans. In this study, we developed a real-time PCR assay to detect T. spiralis DNA in ovine muscle samples that can be used as an alternative surveillance tool to ensure food safety using newly designed primers. The assay is specific for the Scfld4 gene of Trichinella (T1) and enables the detection of larvae in ovine muscle tissue samples with high sensitivity and specificity. Trichuris ovis, Oesophagostomum dentatum, Haemonchus contortus, and Bunostomum trigonocephalum showed no nonspecific amplification. The assay could detect Trichinella DNA concentrations as low as 0.0026 ng/μL, equivalent to 0.0064 larvae, indicating a high sensitivity for T. spiralis detection. We used this real-time PCR to detect 73 ovine muscle samples from an ovine abattoir, and five samples tested positive via real-time PCR but negative via microscopy. This assay may provide a more specific and sensitive method for rapidly detecting Trichinella larvae in ovine muscle tissues.

Retrospective Survey of Human Trichinellosis in a Romanian Infectious Diseases Hospital over a Thirty-Year Interval—The Never-Ending Story

Trichinellosis remains a food-safety risk in Romania due to cultural traditions and food behavior. The aim of the present study was to evaluate the epidemiological, clinical and therapeutical data of all human trichinellosis cases in patients admitted to an Infectious Diseases Hospital from northwestern Romania during a thirty-year interval. Between 1 January 1988 and 31 December 2018, a total of 558 patients were hospitalized with the diagnosis of trichinellosis. The number of cases/year varied between 1 and 86. The source of infection was known for 524 patients, represented by domestic pig meat (n = 484; 92.37%) and wild boar (n = 40; 7.63%). Most patients (410; 73.48%) presented were part of family or group outbreaks. Demographical and clinical data of patients will be presented. Antiparasitic therapy was prescribed in 99.46% of cases, and corticosteroids were prescribed in 77.06% of patients. In total, 48 patients (8.6%) presented complications of trichinellosis: 44 for a single complication (neurological, cardiovascular or respiratory); the others multiple complications. Pregnancy was documented in five patients. No fatalities occurred during the study period. Although the number of hospitalized patients has decreased in the last years, trichinellosis still remains an important public health problem in northwestern Romania.

Untargeted serum metabolomics analysis of Trichinella spiralis-infected mouse

BACKGROUND

Trichinellosis, caused by a parasitic nematode of the genus Trichinella, is a zoonosis that affects people worldwide. After ingesting raw meat containing Trichinella spp. larvae, patients show signs of myalgia, headaches, and facial and periorbital edema, and severe cases may die from myocarditis and heart failure. The molecular mechanisms of trichinellosis are unclear, and the sensitivity of the diagnostic methods used for this disease are unsatisfactory. Metabolomics is an excellent tool for studying disease progression and biomarkers; however, it has never been applied to trichinellosis. We aimed to elucidate the impacts of Trichinella infection on the host body and identify potential biomarkers using metabolomics.

METHODOLOGY/PRINCIPAL FINDINGS

Mice were infected with T. spiralis larvae, and sera were collected before and 2, 4, and 8 weeks after infection. Metabolites in the sera were extracted and identified using untargeted mass spectrometry. Metabolomic data were annotated via the XCMS online platform and analyzed with Metaboanalyst version 5.0. A total of 10,221 metabolomic features were identified, and the levels of 566, 330, and 418 features were significantly changed at 2-, 4-, and 8-weeks post-infection, respectively. The altered metabolites were used for further pathway analysis and biomarker selection. A major pathway affected by Trichinella infection was glycerophospholipid metabolism, and glycerophospholipids comprised the main metabolite class identified. Receiver operating characteristic revealed 244 molecules with diagnostic power for trichinellosis, with phosphatidylserines (PS) being the primary lipid class. Some lipid molecules, e.g., PS (18:0/19:0)[U] and PA (O-16:0/21:0), were not present in metabolome databases of humans and mice, thus they may have been secreted by the parasites.

CONCLUSIONS/SIGNIFICANCE

Our study highlighted glycerophospholipid metabolism as the major pathway affected by trichinellosis, hence glycerophospholipid species are potential markers of trichinellosis. The findings of this study represent the initial steps in biomarker discovery that may benefit future trichinellosis diagnosis.

Chromosome-length genome assembly of Teladorsagia circumcincta - a globally important helminth parasite in livestock

BACKGROUND

Gastrointestinal (GIT) helminthiasis is a global problem that affects livestock health, especially in small ruminants. One of the major helminth parasites of sheep and goats, Teladorsagia circumcincta, infects the abomasum and causes production losses, reductions in weight gain, diarrhoea and, in some cases, death in young animals. Control strategies have relied heavily on the use of anthelmintic medication but, unfortunately, T. circumcincta has developed resistance, as have many helminths. Vaccination offers a sustainable and practical solution, but there is no commercially available vaccine to prevent Teladorsagiosis. The discovery of new strategies for controlling T. circumcincta, such as novel vaccine targets and drug candidates, would be greatly accelerated by the availability of better quality, chromosome-length, genome assembly because it would allow the identification of key genetic determinants of the pathophysiology of infection and host-parasite interaction. The available draft genome assembly of T. circumcincta (GCA_002352805.1) is highly fragmented and thus impedes large-scale investigations of population and functional genomics.

RESULTS

We have constructed a high-quality reference genome, with chromosome-length scaffolds, by purging alternative haplotypes from the existing draft genome assembly and scaffolding the result using chromosome conformation, capture-based, in situ Hi-C technique. The improved (Hi-C) assembly resulted in six chromosome-length scaffolds with length ranging from 66.6 Mbp to 49.6 Mbp, 35% fewer sequences and reduction in size. Substantial improvements were also achieved in both the values for N50 (57.1 Mbp) and L50 (5 Mbp). A higher and comparable level of genome and proteome completeness was achieved for Hi-C assembly on BUSCO parameters. The Hi-C assembly had a greater synteny and number of orthologs with a closely related nematode, Haemonchus contortus.

CONCLUSION

This improved genomic resource is suitable as a foundation for the identification of potential targets for vaccine and drug development.