Zoonotic Taenia infections with focus on cysticercosis due to Taenia solium in swine and humans

Oxidative Stress in Parasitic Diseases-Reactive Oxygen Species as Mediators of Interactions between the Host and the Parasites

Oxidative stress plays a significant role in the development and course of parasitic infections, both in the attacked host organism and the parasite organism struggling to survive. The host uses large amounts of reactive oxygen species (ROS), mainly superoxide anion (O2•-) and hydrogen peroxide (H2O2), to fight the developing parasitic disease. On the other hand, the parasite develops the most effective defense mechanisms and resistance to the effects of ROS and strives to survive in the host organism it has colonized, using the resources and living environment available for its development and causing the host's weakening. The paper reviews the literature on the role of oxidative stress in parasitic diseases, which are the most critical epidemiological problem worldwide. The most common parasitosis in the world is malaria, with 300-500 million new cases and about 1 million deaths reported annually. In Europe and Poland, the essential problem is intestinal parasites. Due to a parasitic infection, the concentration of antioxidants in the host decreases, and the concentration of products of cellular components oxidation increases. In response to the increased number of reactive oxygen species attacking it, the parasites have developed effective defense mechanisms, including primarily the action of antioxidant enzymes, especially superoxide dismutase and nicotinamide adenine dinucleotide phosphate hydrogen (NADPH)-dependent complexes glutathione and thioredoxin.

Isolated Intraventricular Neurocysticercosis: Atypical Presentation of a Colloid Cyst

Neurocysticercosis is a condition characterized by the presence of Taenia solium (larval stage: Cysticercus cellulosae) in the brain and is classified as a tropical disease. Although it was previously uncommon in Europe, the number of cases has been increasing over the past decade. In this report, we present a case of a patient who was admitted with symptoms of raised intracranial pressure and biventricular hydrocephalus, without evidence of infection. Imaging studies revealed the presence of an atypical colloid cyst, which was subsequently removed using a neurosurgical endoscopic approach. Anatomopathologic analysis confirmed the presence of a C. cellulosae larva. It is crucial not to overlook or misdiagnose isolated intraventricular neurocysticercosis because it can lead to complications such as delayed diagnosis and dissemination of the cyst.

The Importance of the Slaughterhouse in Surveilling Animal and Public Health: A Systematic Review

From the point of public health, the objective of the slaughterhouse is to guarantee the safety of meat in which meat inspection represent an essential tool to control animal diseases and guarantee the public health. The slaughterhouse can be used as surveillance center for livestock diseases. However, other aspects related with animal and human health, such as epidemiology and disease control in primary production, control of animal welfare on the farm, surveillance of zoonotic agents responsible for food poisoning, as well as surveillance and control of antimicrobial resistance, can be monitored. These controls should not be seen as a last defensive barrier but rather as a complement to the controls carried out on the farm. Regarding the control of diseases in livestock, scientific research is scarce and outdated, not taking advantage of the potential for disease control. Animal welfare in primary production and during transport can be monitored throughout ante-mortem and post-mortem inspection at the slaughterhouse, providing valuable individual data on animal welfare. Surveillance and research regarding antimicrobial resistance (AMR) at slaughterhouses is scarce, mainly in cattle, sheep, and goats. However, most of the zoonotic pathogens are sensitive to the antibiotics studied. Moreover, the prevalence at the slaughterhouse of zoonotic and foodborne agents seems to be low, but a lack of harmonization in terms of control and communication may lead to underestimate its real prevalence.

Regulation of piglet T-cell immune responses by thioredoxin peroxidase from Cysticercus cellulosae excretory-secretory antigens

Taenia solium (T. solium) cysticercosis is a serious threat to human health and animal husbandry. During parasitization, Cysticercus cellulosae (C. cellulosae) can excrete and secrete antigens that modulate the host's T-cell immune responses. However, the composition of C. cellulosae excretory-secretory antigens (ESAs) is complex. This study sought to identify the key molecules in C. cellulosae ESAs involved in regulating T-cell immune responses. Thus, we screened for thioredoxin peroxidase (TPx), with the highest differential expression, as the key target by label-free quantification proteomics of C. cellulosae and its ESAs. In addition, we verified whether TPx protein mainly exists in C. cellulosae ESAs. The TPx recombinant protein was prepared by eukaryotic expression, and ESAs were used as the experimental group to further investigate the effect of TPx protein on the immune response of piglet T cells in vitro. TPx protein induced an increase in CD4+ T cells in piglet peripheral blood mononuclear cells (PBMCs), while CD8+ T cells did not change significantly. This resulted in an imbalance in the CD4+/CD8+ T-cell ratio and an increase in CD4+CD25+Foxp3+ Treg cells in the PBMCs. In addition, TPx protein initiated T helper 2 (Th2)-type immune responses by secreting IL-4 and IL-10 and suppressed Th1/Th17-type immune responses. The results showed that ESAs were involved in regulating piglet T-cell immune responses cells. This suggests that TPx protein found in ESAs plays an essential role to help the parasite evade host immune attack. Moreover, this lays a foundation for the subsequent exploration of the mechanism through which TPx protein regulates signaling molecules to influence T-cell differentiation.

A Rare Case of Cysticercosis Involving the Whole Spinal Canal

BACKGROUND

Cysticercosis is the commonest parasitic disease to affect the central nervous system (CNS). However, cysticercosis affecting the spine is extremely rare. We reported a rare case of cysticercosis involving the whole spinal canal in China.

CASE PRESENTATION

A rare case of cysticercosis involving the entire spinal cord, in a 52-year-old Chinese man, was detected in 2021. Epidemiological investigation, clinical and etiological examination was performed.

CONCLUSION

Since spinal cysticercosis is a rare but potentially life-threatening disease, clinicians should always consider the differential diagnosis of space-occupying lesions.

Intraperitoneal and intracranial experimental cysticercosis present different metabolic preferences after treatment with isolated or combined albendazole and nitazoxanide

Cysticercosis is a zoonotic public health issue especially severe when the parasite is in the central nervous system although it may be found all over the human organism. Taenia crassiceps cysticerci inoculated in mice is the experimental model used to study cysticercosis. The most used cysticercosis treatment is with albendazole (ABZ). Nitazoxanide (NTZ) has been experimentally tested against this parasite. Metabolic analysis has been used to determine drugs impact on the parasite. The aim of this study was to determine the in vivo metabolic impact of the ABZ-NTZ combination in T. crassiceps cysticerci inoculated in mice peritoneal and intracranial cavities. Mice were experimentally inoculated with T. crassiceps cysticerci in the intraperitoneal cavity or in the intracranial one. Thirty days after the infection they were treated with NaCl 0.9% (control group), 50 mg/kg of ABZ, 50 mg/kg of NTZ or 50 mg/kg of NTZ and ABZ (ABZ/NTZ combination). 24 h after treatment the animals were euthanized and the cysticerci analyzed through high performance chromatography and spectrophotometry in order to detect the glycolytic, mitochondrial and protein catabolism pathways. The intracranial parasites used more intensely the homolactic fermentation while the intraperitoneal ones presented a greater use of the mitochondrial pathways and protein catabolism. Regarding the glycolytic pathways, it was possible to observe a significant impact induced by the drugs used, both isolated or in combination. It was possible to detect an increase in the fumarate reductase pathway after the drugs exposure and no impact in the protein's catabolism. Therefore, the cysticerci showed different uses of metabolic pathways regarding the site of inoculation due to the availability of nutrients inherent of each environment. This study showed the parasite metabolic resilience and capability of use of different biochemical pathways in order to ensure survival in spite of a hostile environment.

Advanced magnetic resonance imaging and spectroscopy in a case of neurocysticercosis from North America

Neurocysticercosis (NCC) is a parasitic infection caused by Cysticercus cellulosae, the metacestode of pork tapeworm (Taenia solium). NCC is one of the most common public health problems worldwide. We present a patient harboring a bilobed ring-enhancing lesion with a presumed diagnosis of brain metastasis, who returned to the USA after traveling to an endemic region. The diagnosis of NCC was established based on a characteristic resonance of succinate on proton magnetic resonance spectroscopy. Also, higher mean diffusivity and lower fractional anisotropy along with relative cerebral blood volume were observed from the lesion compared to contralateral normal brain regions. Multiparametric analysis may improve the differential diagnosis of ring-enhancing intracranial lesions such as NCC.

A retrospective study of Taenia spp. in Cuban patients: what does molecular analysis tell us?

Taeniosis is a neglected disease, particularly in developing countries, and is caused by infection with the adult tapeworm of either Taenia solium, Taenia saginata, and Taenia asiatica. Of these, T. solium is of primary concern due to the potential for cysticercosis should T. solium eggs be ingested. In Cuba, all cases of taeniosis are assumed to be caused by T. saginata, although some cases of cysticercosis have been documented. It is therefore important to gain further insights regarding the species causing taeniosis in Cuba, especially as diagnostic records indicate an increasing incidence, with the highest number of cases reported in 2020. In this study, we analysed 37 Taenia-positive faecal samples (or proglottids isolated from faecal samples) from the period 2001 until 2020 from all regions of the country. Genomic DNA was extracted from the samples, which had been stored in 10% formalin, using the QIAamp Tissue Kit. Species identification was carried out by duplex real-time PCR targeting the mitochondrial DNA. All cases were found to be T. saginata, and sequence analysis of three isolates confirmed the identification of this species. Our data do not provide any evidence that T. solium currently occurs in Cuba. However, given the relatively low number of samples analysed here, that the parasite may be imported with visitors or travellers who have been in endemic countries, and that taeniosis has relatively mild symptoms and thus infected patients may not seek medical attention, we recommend species determination for all taeniosis cases reported in Cuba.

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The incidence of taeniosis cases in Cuba is rising, with 2020 being a peak year

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Although assumed to be Taenia saginata, this has not been confirmed

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We investigated 37 samples from 2001 until 2020 that had been stored in formalin

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Duplex real-time PCR indicated T. saginata; 3 cases were confirmed by sequencing

Insects dispersing taeniid eggs: Who and how?

Taeniosis/cysticercosis and echinococcosis are neglected zoonotic helminth infections with high disease burden caused by tapeworms which circulate between definitive and intermediate host reflecting a predator-prey interaction. Taeniid eggs can remain vital for months, allowing arthropods to mechanically transport them to intermediate hosts. However, the multiple routes that arthropods provide as carriers of taeniid eggs are still often unregarded or not considered. This review focuses on the prevalence and importance of arthropods as carriers and spreaders of taeniid eggs in the epidemiology of taeniosis/cysticercosis and echinococcosis. Current scientific knowledge showed a relevant role of houseflies (Muscidae), blowflies (Calliphoridae), dung beetles (Scarabaeoidea), darkling beetles (Tenebrionidae), ground beetles (Carabidae) and skin beetles (Dermestidae) in the spread of taeniid eggs in the environment, which may favor the infection of new hosts through the direct ingestion of an insect or of contaminated food and water. At last, key research challenges are highlighted, illustrating that further knowledge on the topic is needed to develop and improve guidelines and actions to prevent taeniid infections worldwide.