The current prevalence and diversity of cystic echinococcosis in slaughtered animals in Egypt

Anatomopathological characterization of branchial cysts in slaughtered pigs

Branchial cysts are a congenital anomaly in humans and other animal species. In this study, twenty commercially bred slaughtered pigs ranging from 120 to 150 days of age, sourced from different farms and lots, were found to have cysts in the oropharyngeal region at meat inspection despite the absence of clinical signs. Two cysts were selected for histopathological examination. The first cyst was surrounded by fibrous connective tissue and lined by a simple single cell layer of epithelium. The second cyst comprised a squamous pseudostratified to simple stratified epithelium, accompanied by a mild inflammatory infiltrate. This cyst was also surrounded by fibrous connective tissue and glands. The pathological diagnosis of branchial cysts in slaughtered pigs was established on the basis of their anatomical location and gross and microscopic findings.

A Novel Designed Sandwich ELISA for the Detection of Echinococcus granulosus Antigen in Camels for Diagnosis of Cystic Echinococcosis

Echinococcus spp. are important cosmopolitan zoonotic parasitic tapeworms that cause a disease called hydatidosis or cystic echinococcosis (CE), which has remarkable economic losses. The objective of our study was to develop a specific IgG polyclonal antigen-based ELISA (Sandwich ELISA; capture ELISA) method for the detection of circulating Echinococcus granulosus (E. granulosus) antigens in camels infected with hydatid cysts before slaughtering and its application in serodiagnosis of CE in animals to assess the positive rate of hydatidosis in camels slaughtered in Giza governorate abattoirs in Egypt. In this study, molecular identification of Echinococcus sp. isolate was performed based on the NADH dehydrogenase subunit 1 (NAD1) gene, revealing the isolate (GenBank: OQ443068.1), which is identical to the G6 E. granulosus sensu lato genotype. The positive rate of hydatid cysts was determined in slaughtered camels' organs (n = 587). The results revealed that hydatid cysts were found in 46.5% (273/587) of the examined camels. Pulmonary echinococcosis was significantly more prevalent in the slaughtered camels (60%, 164/273) than hepatic echinococcosis (39.9%, 109/273), (p = 0.001, Chi Square = 11.081). Cyst fertility rates were higher in hepatic (90.8%, 99/109) than in pulmonary cysts (83.5%, 137/164) and the most viable protoscoleces were recorded from fertile the hepatic cysts (67.85 ± 12.78). In this study, hydatid cyst germinal layer antigen (GlAg) was isolated and used for the immunization of rabbits to raise IgG polyclonal antibodies (anti-Echinococcus GlAb IgG). These IgG polyclonal antibodies were purified by affinity chromatography using a protein A column, then labeled with horseradish peroxidase. Electrophoretic analysis of IgG polyclonal antibodies and crude GlAg was performed in 10% polyacrylamide gels. The SDS-PAGE revealed four bands at molecular weights of 77 kDa, 65 kDa, 55 kDa, and 25 kDa. The Sandwich ELISA was performed to evaluate the sensitivity and specificity and cross-reactivity of the prepared IgG polyclonal antibodies. The circulating hydatid antigen was found in 270 out of the 273 samples with hydatidosis, with a sensitivity of 98.9% (270/273), a specificity of 94.9% (296/312) and a diagnostic efficacy of 96.8%. Regarding the cross reactivity, anti-Echinococcus GlAb IgG showed a low cross-reactivity with Fasciola gigantica infected camel sera (3/8), and Myiasis (Cephalopina titillator larvae; 3/20). No cross-reactivity was recorded with uninfected camel sera (negative sera for E. granulosus), and no cross-reactivity was found with antigens of Eimeria spp., Toxoplasma gondii, Cryptosporidium sp., and Hyalomma dromedarii (ticks' infestation). Then, Sandwich ELISA was conducted again to detect E. granulosus antigen in all the collected camel sera, which resulted in a 48.7% (286/587) positive rate of CE compared to 46.5% (273/587) using a postmortem inspection (PM diagnosis) (p = 0.5, Chi Square = 0.302). In conclusion, the Sandwich ELISA technique introduced in this study appears to be a sufficiently sensitive diagnostic assay for the detection of camels' echinococcosis using anti-Echinococcus GlAb IgG. In addition, it might offer a significant medical and veterinary importance in helping the early detection of hydatidosis, as well as its early treatment.

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.

Pathological Findings and Oxidative Stress Status Associated with Hydatidosis in Dromedary Camels

(1) Background: Cystic echinococcosis is a zoonotic helminth disease that causes severe economic losses. The study aimed to assess the prevalence and viability of cystic echinococcosis in examined camels. In addition, assessing the histological, morphological, oxidative, and antioxidant state related to the cystic echinococcosis infection; (2) Methods: The study was performed on 152 slaughtered dromedary camels between March and September 2022 at El-Basatin abattoir in Cairo Governorate, Egypt; (3) Results: The results revealed that the prevalence of hydatidosis was 21.7% in slaughtered camel and the highest infection rate observed in lungs was 87.87%, while it was 9% in livers. Camels' liver infections were rare, whereas their lung infections were more common. By comparing to non-infected camels, the level of MAD was significantly increased with hydatid cysts infection, while the level of GSH, SOD and CAT was significantly decreased. Histopathological section of camel cyst revealed layered membranes surrounded by a zone of cellular infiltration and an outermost fibrous tissue reaction. In addition, there was evidence of atelectasis, emphysema, hemorrhage, congestion, and fibrosis in the surrounding tissues. Nonetheless, the degeneration and necrosis of hepatocytes and other pathological alterations in liver cyst sections were remarkably comparable to those seen in the lungs. Furthermore, calcification was detected.

Occurrence and Phylogenetic Description of Cystic Echinococcosis Isolate from Egyptian Camel (Camelus Dromedarius)

Cystic echinococcosis is one of the most significant cyclo-zoonotic diseases of major economic and public health significance worldwide. The current study was carried out to determine the epidemiological profile of cystic echinococcosis as well as to investigate its molecular and phylogenic status from one-humped camel (Camelus dromedarius) in the southern region of Egypt. In the present work, 110 camels freshly slaughtered at Daraw abattoirs, Aswan governorate were inspected for the presence of Hydatid cysts (HCs) visually and manually by palpation and incision, over a period of one year (June, 2018 - May, 2019). Furthermore, fourteen fertile hydatid cyst samples were collected from lungs of slaughtered camels. DNA extraction from two fertile samples was successfully achieved followed by phylogenetic analysis on two mitochondrial genes (cox1and nad1). Out of 110 camels slaughtered 11 (10 %) were found harboring hydatid cysts. The infection was found to prevail throughout the year, with the highest peak encountered in winter (45.5 %). The lungs were the most frequently infected organs (72.7 %) with liver cysts occurring at a significantly lower rate (27.3 %). The mean value of total protein, glucose, urea, cholesterol, magnesium, potassium, copper and creatinine was higher in cystic fluid from camels as compared to cattle. Blast and phylogenetic analysis on sequenced genes showed the presence of Echinococcus intermedius, originally the pig genotype (G7) in camels for the first time in Egypt. To the best of our knowledge, the current research provides a description of the current epidemiological and molecular situation of camel hydatidosis in the southern region of Egypt. Furthermore, the current results may have significant implications for hydatid disease control in the studied region.

Autoimmunity in human CE: Correlative with the fertility status of the CE cyst

Cystic echinococcosis is speculated to exert several immune-evasion strategies involving autoimmune-phenomena. We evaluated the hypothesizes that the prevalence of autoantibodies increases in the sera of CE patients that may evidence the association between the parasite and autoimmune diseases. Sera from 63 subjects at distinct types of CE cyst fertility were investigated for antinuclear antibodies (ANA), and anti-CCP antibodies. Plasma levels and cellular production of IL-17A cytokine were specifically defined as being assumed to prime for autoimmunity. Healthy-controls were age and gender-matched to test sera. ANA expressions inside the surgically removed metacestode and adventitial layer were also assayed. Out of 63 patients, 35 % had fertile highly viable cysts (group-1), 41 % had fertile low viable cysts (group-2) and 24 % had non-fertile cysts (group-3). A four-fold increase in ANA sera-levels was detected in group-1 compared with their controls (p-value 0.001) while anti-CCP levels were of insignificant differences. In group-2 and group-3, no significant differences were detected between ANA and anti-CCP sera-levels in CE patients and their controls. IL-17A sera-levels in group-1 and group- 2 were significantly higher than their healthy-controls while being of insignificant differences in group-3, p-value= 0.300. No association was detected between sera-levels of IL-17A and ANA as well as anti-CCP antibodies. Interestingly, relative IL-17A cellular expression associated positive ANA deposition in the parasite cells and adventitial layer. Collectively, based on the parasite fertility, IL-17A and ANA seemed to be involved in the host immune defenses against CE. There is no association between CE and anti-CCP antibodies.

Cystic Echinococcosis in Slaughtered Cattle and Sheep from North Macedonia

Cystic echinococcosis is a cosmopolitan zoonotic infection, commonly seen in areas where livestock and dogs are kept together. The objective of this study was to investigate the prevalence of echinococcosis in slaughtered cattle and sheep in North Macedonia and to evaluate the location and fertility/sterility rates of the cysts. A total of 302 slaughtered animals were examined with visual inspection, palpation, and incision of the internal organs in order to detect cysts. Microscopic examination was carried out to determine the presence of protoscoleces. The overall prevalence of echinococcosis in slaughtered cattle and sheep was 60%. The presence of cysts increased with age in cattle. In both cattle and sheep, the most common affected organs were the liver and lungs infected with more than one cyst. The findings showed higher fertility rate in sheep which confirmed their role as the most important intermediate host. This study shows that North Macedonia is an endemic region, and serious control strategies should be implemented, with special emphasis on safety disposal of infected organs and anthelmintic treatment of the dogs.

Histological and immunological insights to hydatid disease in camels

PURPOSE

To investigate the immuno-histological evidences in viable and non-viable hydatid cysts obtained from naturally infected camels.

METHODS

A cohort study (February 2018-December 2019), a total of 15 hydatidosis-infected camels from slaughter houses in Cairo were involved. Specimens were investigated for parasite viability, liver histological changes, IL-17A cytokine immunohistochemical expressions in the adventitial layer, and the anti-nuclear antibodies (ANAs) immunofluorescent expression in the metacestode's structures. Real-Time Quantitative -Morphocytometry and SPSS were utilized.

RESULTS

Multi-focal lesions and high viability were found in 60% of the cases. Overall accumulation of collagen associated the parasite establishment that involved infiltrations of mononuclear cells with significantly increased IL-17A expression. Interestingly, the ANAs appeared to have a role in the immune-defense against the metacestode showing different patterns. ANAs production correlated with IL-17A expression and the viability of the parasite.

CONCLUSION

IL-17A responses in hydatidosis is associated with collagen deposition and ANA production as a sort of anti-parasite immunity in a viability dependent manner.

Epidemiological, Morphometric, and Molecular Investigation of Cystic Echinococcosis in Camel and Cattle From Upper Egypt: Current Status and Zoonotic Implications

Cystic echinococcosis has been considered one of the major parasitic zoonoses which is associated with severe economic losses. The present study was undertaken to investigate the occurrence, organ distribution, cyst fertility, and viability of cystic echinococcosis in slaughtered camels and cattle from various abattoirs in Assiut Governorate, Egypt. The work also involved morphological, morphometric, and molecular identification of the parasite. The occurrence of hydatid cysts was investigated in total number of 100 lungs of camels and 574 liver and lungs of cattle admitted to three slaughterhouses at Assiut Governorate, Egypt. Moreover, several individual variable factors, including organ involvement, age, sex, and hydatid cyst characteristics, were studied to identify their possible association with the occurrence of the disease. Genomic DNA was extracted from the hydatid cysts, followed by molecular identification of the parasite through amplification of ribosomal DNA internal transcribed spacer (ITS) regions. Hydatid cysts were found in 6 camels (6%) out of 100 inspected camels, while 5 hydatid cysts (0.87%) were detected in a total number of 574 cattle examined. The parasite was detected exclusively in lungs of camels, while lungs were the main organ infected by the parasite in cattle and one hydatid cyst was found in the liver (0.17%). In camel, 66.7, 16.65, and 16.65%of detected cysts were fertile, sterile, and calcified, respectively, while in cattle, these percentages were 60, 20, and 20%, respectively. None of the studied variable factors were significantly associated with the occurrence of the disease in camels, with the exception that all cysts were found in the lung. Conversely, we found a significant association (P < 0.05) between the age and sex of the slaughtered cattle and the occurrence of hydatid cysts. In this respect, the rate of infection was higher in female cattle and those cattle more than 5 years (P < 0.05). The morphological, morphometric, and molecular studies confirmed the presence of the parasite. Taken together, our results concluded that camels and cattle play a potential role in maintaining the transmission cycle of this zoonotic parasite.

The global status and genetic characterization of hydatidosis in camels (Camelus dromedarius): a systematic literature review with meta-analysis based on published papers

Hydatidosis is a potential zoonotic helminthic disease affecting a broad spectrum of mammals, including humans, worldwide. The current review was conducted to investigate the genotypic status and prevalence of hydatid disease in camels across the world. For the purpose of the study, the articles addressing the worldwide prevalence of hydatidosis in camels were searched in several English language databases. The search process resulted in the inclusion of 122 papers. Based on the data presented in the reviewed articles, the pooled prevalence of hydatid disease in camels across the world was measured at 23.75% (95% CI 20.15-27.55). Moreover, the subgroup analysis demonstrated significant differences in the overall prevalence of hydatidosis among camels based on year, geographic area, climate parameters, camel population, gender, infected organ, fertility rate of the cyst and laboratory diagnostic technique. Furthermore, the Echinococcus granulosus genotypes identified in camels with hydatidosis included G1, G2, G3, G1-G3, G5, G6, G7, G6-G7 and G6-G10, with G6 being the most common genotype throughout the world. The data obtained from the current study are central to the better conceptualization of the biological and epidemiological characteristics of E. granulosus s.l. genotypes around the world, which can be helpful in the planning and adoption of more comprehensive control strategies.

Predicting the outcome of asymptomatic univesicular liver hydatids: diagnostic accuracy of unenhanced CT

OBJECTIVES

To establish the role of unenhanced CT in predicting the outcome of liver hydatid cysts. We sought to determine whether the presence of laminated membrane detachment (LMD) or pericyst degenerative changes (PDCs) detected on CT were reliable signs for predicting a favorable outcome of liver hydatids.

METHODS

In a 20-year-long study, we prospectively followed changes occurred in CT of 106 cysts of 98 patients with incidentally discovered asymptomatic univesicular liver hydatids who accepted to enter a watch-and-wait program. An "unfavorable" outcome was defined as the occurrence of a complication (most commonly, cyst fistula or infection) or increase in the cyst size during the follow-up; otherwise, the outcome was considered "favorable." The parameters derived from a binary logistic regression analysis (with the outcome taken as the dependent variable), after appropriate transformation of the independent variables (presence of LMD or PDCs on CT), were used to calculate the sensitivity, specificity, positive and negative likelihood ratios, and positive and negative predictive values of the presence of either the abovementioned CT findings for the prediction of a favorable outcome.

RESULTS

The presence of LMD or PDCs had a high specificity (88%) and positive predictive value (96%) for a favorable outcome; they had high false-negative rates.

CONCLUSIONS

The presence of either LMD or PDCs on unenhanced CT, in incidentally discovered asymptomatic univesicular liver hydatids, was associated with a high probability of a favorable outcome. Their absence does not rule out a favorable outcome.

KEY POINTS

• Computed tomography can be used for predicting the outcome of those with incidentally discovered univesicular liver hydatids. • The presence of laminated membrane detachment and/or pericyst degenerative changes is associated with a favorable outcome. • Their absence does not necessarily indicate an unfavorable outcome.

Cystic echinococcosis in humans and animals in Egypt: An epidemiological overview

Cystic echinococcosis (CE), caused by the cestode Echinococcus granulosus (sensu lato), is a serious neglected zoonotic disease in many parts of the world, including Egypt. Thus far, the actual incidence of CE in the Egyptian population remains unknown. Infection with E. granulosus (s.l.) is common among stray dogs in rural and suburban areas owing to the spread of parasite eggs. Herein, we present an updated review of published data on the incidence of CE in humans and animals as well as the genotypes prevalent in Egypt. CE occurs in most parts of Egypt; however, available data are mostly from northern Egypt, particularly Cairo and Giza. In southern Egypt, the disease is likely to be underdiagnosed or underreported. A few risk factors were studied. In the Egyptian population, residency in rural areas, farming, and age were significant factors for acquiring CE. In livestock, age, sex and season have been associated with high prevalence of CE. Several genotypes have been identified among livestock (G1, G4, G5, G6 and G7) and humans (G1, G6 and G7). This literature review underscores the need for a precise national surveillance system to track CE distribution in humans and animals and design appropriate preventive and control strategies for this disease.

•

A review summarizing the epidemiological data for Echinococcus granulosus (s.l.) infections in Egypt.

•

Egypt is an endemic area for cystic echinococcosis in the human population and livestock.

•

Genotypes G1, G4, G5, G6 and G7 of E. granulosus (s.l.) were reported in Egypt.

•

A national surveillance system to track cystic echinococcosis in Egypt is needed.

Prevalence and bacterial isolation from hydatid cysts in dromedary camels (Camelus dromedarius) slaughtered at Sharkia abattoirs, Egypt

Cystic echinococcosis (CE) is a severe neglected zoonotic parasitic disease caused by the larval stage of the dog tapeworm, Echinococcus granulosus. The objectives of this study were to determine the prevalence of hydatid cysts in dromedary camels (Camelus dromedarius) at Sharkia province, Egypt and investigate the occurrence of bacteria in hydatid fluid. A total of 6416 dromedary camels slaughtered in five abattoirs in Sharkia province, Egypt during the period from January and December 2018 were investigated for the presence of hydatid cysts. Furthermore, the bacterial species in 10 hydatid fluid isolated from lungs and livers was identified. The current findings revealed that the prevalence of hydatid cysts was 3.7%. Among those, the infection rate in lungs was 78.2%, which was significantly higher than hepatic infections (21.8%). The prevalence of hydatid cysts was the highest in winter (7.4%) and the lowest in spring (1.5%). The most common bacterial species found inside hydatid fluid collected from lungs were Salmonella spp., Staphylococcus spp., Enterococci and Pseudomonas spp. Meanwhile, Staphylococcus spp. were isolated from hepatic hydatid fluid. In conclusion, hydatid cysts infection is prevalent in dromedary camels in Sharkia province, Egypt as well as various aerobic and anaerobic bacterial species were isolated from hydatid fluid from camel lungs and livers.