Presence Of Cysticerci Research Articles

Spatiotemporal monitoring of Cysticercus pisiformis in European wild rabbit (Oryctolagus cuniculus) in Mediterranean ecosystems in southern Spain

Cysticercosis in wild lagomorphs is caused by Cysticercus pisiformis, the larval stage of Taenia pisiformis. Although previous studies have reported the presence of T. pisiformis in different wild carnivore species, information about the prevalence of C. pisiformis in their intermediate hosts is still very scarce. An epidemiological surveillance program was carried out to determine the prevalence and spatiotemporal patterns of cysticercosis in wild rabbits (Oryctolagus cuniculus) from Spanish Mediterranean ecosystems. A total of 2,923 animals were sampled in 164 hunting estates from Andalusia (southern Spain) during four study periods: 2009−2012 (P1), 2012−2015 (P2), 2015−2018 (P3) and 2018−2020 (P4). The presence of cysticerci was assessed by macroscopical examination and a subset of the collected parasites were molecularly identified by conventional PCR targeting the ITS-1 and 12S rRNA partial genes of Taenia spp. Risk factors associated with cysticercus infection were assessed by generalized estimating equation (GEE) analysis. A spatial statistical analysis was carried out using a Bernoulli model to identify statistically significant spatial clusters. Cysticercus infection was confirmed in 81 (2.8 %; 95 % CI: 2.2–3.4) rabbits. Cysticerci from 18 infected animals were molecularly identified as T. pisiformis. The GEE model showed the study period as the only risk factor associated with C. pisiformis infection in wild rabbits. Significantly higher prevalence was found in P2 (6.1 %; 95 % CI: 4.4−8.4) compared to the rest of the periods. At least one cysticerci-positive animal was detected in 41 (25.0 %; 95 % CI: 18.4–31.6) out of the 164 hunting estates. No statistically significant spatial clusters of high cysticercus prevalence were identified. Our results indicate an endemic circulation of C. pisiformis in wild rabbits in southern Spain. The spatial results highlight a widespread distribution of this parasite in their populations. Further studies should focus in determining which sympatric species may act as definitive hosts for T. pisiformis and the relevance of other potential intermediate host species (e.g. hares and rodents), as the relevance of wild rabbits in the sylvatic cycle of this cestode in Mediterranean ecosystems seems to be low.

Diversity and burden of helminthiasis in wild ruminants in Iran.

This paper aimed to investigate the diversity and burden of helminthiasis in Ovis orientalis (n = 26), Capra aegagrus (n = 29) and Gazella subgutturosa (n = 24) grazed in 37 National Parks in 9 provinces of Iran. The organs and body cavities infected by helminths included gastrointestinal tract, peritoneal cavity, heart, liver and lungs. The contents were extracted and washed under running water and intestinal and lung-isolated nematodes were cleared in lactophenol and subsequently fixed, and cestodes were stained with alum carmine and mounted en face in Berlese's fluid under slight pressure between a microscopic slide and cover slip. The helminth species identified in this study include: intestinal nematodes (Marshallagia marshalli, Teladorsagia circumcincta, Ostertagia ostertagi, Nematodirus oiratianus, Nematodirella longispiculata, Skrjabinema ovis, Trichuris ovis, Trichuris discolor, Parabronema skrjabini), lungworms (Protostrongylus rufescens, Cystocaulus ocreatus), adult cestodes (Moniezia expansa, Helicometra giardi, Avitellina centripunctata, Stilesia globipunctata) and metacestodes (Cysticercus spp., hydatid cyst, Cysticercus tenuicollis). The proportion of the different helminth species ranged from low to moderate (3.45-46.15%) and the intensity of helminth isolation from the different ruminants ranged between 2 and 20. All the taxa identified in our study have been reported in wild animal species around the world. The presence of Cysticercus spp. with cardiac involvement in G. subgutturosa and all helminths of C. aegagrus was reported for the first time in Iran. A significant reduction was observed in worm burden, compared with previous studies in Iran, indicating changes in wildlife host-parasite systems, which can be linked to many reasons including climate changes, public health policies (e.g., strategic anthelmintic use in domestic ruminants), anthropogenic factors and environmental changes (e.g., urbanization or agricultural expansion, physical barriers), as well as vegetation growth and host availability.

Epidemiology of infections with zoonotic pig parasites in Enugu State, Nigeria.

Pig production is an important component of animal agriculture in Nigeria but zoonotic parasites constrain the production and make pork unsafe for human consumption. This epidemiological study was therefore conducted, to ascertain the prevalence and determinants of Taenia solium cysticerci and Ascaris spp infections in pigs in Enugu State. Presence of cysticerci was determined by post-mortem examination of pig carcasses while pig faeces were coprologically examined for presence of Ascaris spp egg, according to standard parasitological protocol. Structured questionnaire was used to elicit information on pig farmers' involvement in practices predisposing to parasitic infections and deworming progammes in 107 piggeries surveyed. Cysticerci were detected in 3.51% (12/342) of pig carcasses inspected. Overall prevalence of Ascaris spp. infections were 38.3% (41/107) and 14.3% (63/441) at farm and individual pig levels respectively. Major determinants of the infection and the percentage of farmers involved were: eating on duty (66.4%), open defecation (35.5%) and semi-extensive husbandry system (62.3%). Others are non-availability of deworming programme (54.4%), rearing pigs of different ages together (41.9%), non-disinfection of feeding or water troughs (41.2%) and early weaning (54.3%). Cognizant of the zoonotic potentials of Ascaris spp and Taenia solium cysticerci, the prevalence found for the parasites are significant from public health and food safety points of view. This underscores the need for cost-effect control measures against the parasites, using a coordinated One Health approach; in order to boost pig production, limit spread of the zoonoses and hence, the public health consequences thereof.

Demyelination in experimental intraventricular neurocysticercosis.

Neurocysticercosis (NCC) is classified as a neglected tropical disease, which affects mainly Latin America and Africa in spite of some reports in North America and Europe. NCC represents the cause of up to 30% of the reported cases of epilepsy in endemic countries. The NCC injuries present direct relation to the development stage, location, and number of parasites as well as to the host immune response. This study aimed the characterization of the inflammatory response and tissue injuries by means of the analyses of the periventricular and parenchymatous demyelination through the experimental intraventricular NCC infection. Therefore, BALB/c mice were submitted to experimental NCC inoculation with Taenia crassiceps cysticerci. Their brains were removed at 7, 30, 60, and 90 days after the inoculation (DAI), and analyzed after staining with hematoxylin and eosin (HE), Luxol Fast Blue, and Nissl. It was possible to observe ventriculomegaly, inflammatory infiltration composed by polymorphonuclear and mononuclear cells, and foamy macrophages. The presence of inflammatory cells was associated with neurodegeneration detected by the areas with demyelination observed initially in the periventricular area and lately in the parenchyma. In conclusion, the presence of cysticerci and the consequent inflammation were able to promote initial periventricular demyelination followed by parenchymatous demyelination as the infection progressed.

Co-occurrence of swine cysticercosis due to Taenia solium and Taenia hydatigena in ethnic minority villages at the Thai-Myanmar border.

As part of the international joint projects working towards the control of taeniosis/cysticercosis in Asia Pacific, epidemiological studies on Taenia solium cysticercosis have been carried out in high-incidence populations, such as minority groups in Thailand. To assess the epidemiology of cysticercotic infections in pigs in the hill-tribe minority villages (Karen) in Tak province, Thailand, we conducted serological screening and necropsies. The patterns of antibody response to T. solium antigens were then investigated using immunoblot assays. Of the 188 pig serum samples tested for antibody responses to partially purified low-molecular-weight antigens of T. solium cyst fluid, positive responses were detected in 37 samples (19.7%). Based on these results, 16 pigs (10 seropositive and 6 seronegative) were necropsied for investigation of cysticerci and intestinal parasites. All seropositive pigs were coinfected with both T. solium and Taenia hydatigena cysticerci, except one, which was infected with T. hydatigena alone. Three of the six seronegative pigs were confirmed to be infected with T. hydatigena. Pigs infected with T. solium showed much stronger antibody responses than those infected with T. hydatigena. Our results demonstrate the co-occurrence of two swine cysticercoses due to T. solium and T. hydatigena in the studied areas. This study also reveals the importance of direct confirmation of the presence of cysticerci by necropsy after serological screening. In addition to the prevalence of swine cysticercosis in these endemic areas, our findings also reveal potential implications for the development of serological diagnostic assays for swine cysticercosis.

New insights in cysticercosis transmission.

Taenia solium infection causes severe neurological disease in humans. Even though infection and exposure to swine cysticercosis is scattered throughout endemic villages, location of the tapeworm only explains some of the nearby infections and is not related to location of seropositive pigs. Other players might be involved in cysticercosis transmission. In this study we hypothesize that pigs that carry nematodes specific to dung beetles are associated with cysticercosis infection and/or exposure. We carried out a cross-sectional study of six villages in an endemic region in northern Peru. We euthanized all pigs (326) in the villages and performed necropsies to diagnose cysticercosis. For each pig, we counted cysticerci; measured anti-cysticercus antibodies; identified intestinal nematodes; tabulated distance to nearest human tapeworm infection; and recorded age, sex, productive stage, and geographic reference. For the purpose of this paper, we defined cysticercosis infection as the presence of at least one cysticercus in pig muscles, and cysticercosis exposure as seropositivity to anti-cysticercus antibodies with the presence of 0–5 cysticerci. Compared to pigs without nematode infections, those pigs infected with the nematode Ascarops strongylina were significantly associated with the presence of cysticerci (OR: 4.30, 95%CI: 1.83–10.09). Similarly, pigs infected with the nematode Physocephalus sexalatus were more likely to have cysticercosis exposure (OR: 2.21, 95%CI: 1.50–3.28). In conclusion, our results suggest that there appears to be a strong positive association between the presence of nematodes and both cysticercosis infection and exposure in pigs. The role of dung beetles in cysticercosis dynamics should be further investigated.

Clinico‐pathological spectrum of gallbladder disease in children

Because of wide variation in clinico-pathological spectrum of gallbladder disease in children the world over, the data of gallbladder disease from this stone belt of India were analysed. Children who underwent cholecystectomy over a period of 8 years January 2002-December 2009 were reviewed. Out of 7076 cholecystectomies, 56 (0.79%) were in children. Thirty-nine (69.6%) children were 11-16 years of age. Thirty-seven (66.07%) children were girls and nineteen (33.9%) were boys. In 12 (21.4%) children, cholecystitis was acalculus. Five (8.9%) children had associated haemolytic disease and 4 (7.1%) children had congenital anomaly in the form of choledochal cyst. Ultrasound findings were available in 44 cases and showed cholelithiasis in 36 cases. Twenty-two (39.3%) children had mixed cholelithiasis, 8 (14.2%) pigment cholelithiasis, 10 (17.8%) combined cholelithiasis and 4 (7.1%) patients had small concretions. Microscopically, changes of chronic cholecystitis were seen in 98.2% while 1.7% showed acute on chronic cholecystitis. There was single unusual case of cysticercus in the wall of the gallbladder. The frequency of gallstone disease is 0.79%. Nonhaemolytic type of cholelithiasis is more common than haemolytic type in this region. Presence of cysticercus in the gallbladder wall in one case was an unexpected finding.

Experimental intravitreous cysticercosis.

Cysticercosis is one of the parasitic diseases that most frequently affects the eye. The most common and severe manifestations of ocular infection are secondary to posterior segment involvement, which often leads to blindness and atrophy of the eye. The pathogenesis of ocular injury in this disease is poorly understood. The authors have developed an experimental animal model for intravitreous cysticercosis using New Zealand rabbits and Taenia crassiceps cysticerci. Twelve rabbits were divided into two groups. Rabbits in group I were inoculated with one living cysticercus in the vitreous cavity. Rabbits in group II received an intramuscular dose of steroids prior to inoculation of parasites. An intense inflammatory reaction, which lead to a severe ocular injury, was observed in rabbits of group I, while rabbits in group II had minimal inflammatory changes. Histopathological studies showed a severe histiocytic infiltrate with generalized retinal damage in group I, and a mild inflammatory infiltrate, limited to the area of direct contact with the parasite in group II. The ocular lesions found in rabbits which did not receive steroids (group I) resembled those found in human ocular cysticercosis. These observations indicate that ocular damage in this parasitic disease might be directly related to inflammatory changes produced by the presence of cysticerci. This model appears to be useful for future investigations.

Neurocysticercosis in an Orthodox Jewish community in New York City.

From June 1990 through July 1991, intracerebral infection with the larval stage of the pork tapeworm Taenia solium was diagnosed in four unrelated persons in an Orthodox Jewish community in New York City. None of the patients had eaten pork, and only one had traveled to a country in which T. solium infection was endemic. We investigated this outbreak, screened serum samples from family members and household contacts for antibodies to cysticercosis, and examined stool specimens from household employees for eggs of taenia species. The four patients had recurrent seizures and brain lesions that were radiologically consistent with the presence of cysticerci. The diagnosis was confirmed in two patients by a brain biopsy, and in two by immunoblot assays for cysticercus antibodies. Of 17 immediate family members screened serologically, 7 from two families had cysticercus antibodies. Magnetic resonance imaging of the brain showed cystic lesions in two of the seropositive family members, one of whom had had a seizure. Examinations of six domestic employees from all four households revealed an active infection with taenia species in one and a positive serologic test in another. Since these women had recently emigrated from Latin American countries where T. solium infection is endemic, they were the most likely sources of infection in the members of these households. A diagnosis of neurocysticercosis should be considered in patients with seizures and radiologic evidence of cystic brain lesions, even in those who do not eat pork and who have not traveled to a country in which T. solium infection is endemic. Recent emigrants from countries in which T. solium infection is endemic should be screened for tapeworm infection in their stools before they are employed as housekeepers or food handlers.

A Case of Pulmonary Cysticercosis

Cysticercosis, which has a worldwide distribution is found in man, who is usually infected by eating inadequately cooked pork or other contaminated food. Cysticercosis develops most commonly in the muscles and brain. Pulmonary involvement is very rare and also difficult to recognize because pulmonary lesions caused by the presence of cysticerci are difficult to discern from pulmonary infiltrates, because other parasitic infestations or tuberculosis, as well as metastatic lesions, produce similar chest X-ray findings and similar clinical symptoms.We experienced a case of pulmonary cysticercosis confirmed at Gyeongsang National University Hospital by means of an open lung biopsy and treated successfully with praziquantel (50 mg/kg per day for 15 days).This case seems to indicate that pulmonary cysticercosis should be considered as a diagnostic possibility in patients with nodular infiltrates in the lungs, especially in endemic areas, until such infiltrates are otherwise explained.

CYSTICERCI IN PROCESSED MEAT IN GUATEMALA.

SummarySamples of sausages and frankfurters collected in 176 stores in Guatemala City (in a 20% random sample of 3,758 food establishments) were examined for the presence and viability of cysticerci. Cysticercus cellulosae (1–45 per sample) was found in 6 percent of 99 pork sausage, 6.5 percent of 107 Spanish-type sausage, and none of the 6 cocktail sausage or 77 frankfurter samples. The cysticerci were unencapsulated and none of 82 incubated in saline-bile mixture evaginated. C. bovis would not be expected to survive or to be detectable in beef sausages. Three types of tests (evagination in saline-bile mixture and in pure bile, and activity of flame cells) with cysticerci in experimentally prepared pork and Spanish-type sausage equally indicated a rapid loss of viability, as none survived longer than 3 days. Nevertheless, the presence of the cysticerci in processed meat indicates poor rural environmental sanitation, deficient inspection of meat, and clandestine butchering of hogs.