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

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.

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.

Bacterial and Fungal Occurrence in Hydatid Cysts from Livestock in Central Iran

Echinococcus granulosus sensu lato causes Cystic echinococcosis. This study investigated the bacterial and fungal species in the liver and lung hydatid cysts obtained from sheep, goats, cattle, and camels slaughtered in Yazd abattoir, Central Iran. In this study, 84 hydatid cysts were obtained from 20 sheep, 13 goats, 25 cattle, and 26 camels. The fertility and viability rates were assessed using light microscopy and eosin staining, respectively. The aspirated hydatid cysts were cultured to detect the presence of any bacteria and fungi. Bacterial isolates were identified by biochemical tests. DNA was also extracted from germinal layers, and then genotyping was carried out targeting the cox 1 gene. The statistical analysis was performed by SPSS version 16.0. This study showed that 22.62% (19/84) of hydatid cysts had bacterial occurrence, and none of the samples had fungal species. Among the fertile cysts, 52.6% had bacterial occurrence, of which 40% were viable. Most bacteria detected in hydatid cysts included Staphylococcus saprophyticus, Escherichia coli, and S. epidermidis. Hydatid cysts with bacterial occurrence were identified as G1-G3, G5, and G6/G7. The bacterial species occurrence in hydatid cysts had no significant relationship with fertility and viability (P > 0.05), without any significant relation with viability (P > 0.05), animal species (P > 0.05), involved organ in animals (P > 0.05), and hydatid cyst genotypes (P > 0.05). It should also be mentioned that this is the first study to assess the relationship between hydatid cyst genotyping and the occurrence of fungal and bacterial species.

Ruta graveolens, Peganum harmala, and Citrullus colocynthis methanolic extracts have in vitro protoscolocidal effects and act against bacteria isolated from echinococcal hydatid cyst fluid

Echinococcosis is a common and endemic disease that affects both humans and animals. In this study, the in vitro activities of methanolic extracts of Ruta graveolens, Peganum harmala aerial parts, and Citrullus colocynthis seeds against protoscolosis and isolated bacterial strains from hydatid cysts were assessed using disc diffusion methods and Minimum Inhibitory Concentration (MIC). The chemical composition of three methanolic extracts was studied using LC-MS. After 3 h of exposure to 40 mg/mL R. graveolens extract, a tenfold protoscolocidal effect was seen when compared to the convintional medication (ABZ) for the same duration (P < 0.05). The bacteria listed below were isolated from hydatid cyst fluid collected from a variety of sick locations, including the lung and liver. Micrococcus spp., E. coli, Klebsiella oxytoca, Enterobacter aerogenes, Enterobacter amnigenus, Pseudomonas aeruginosa, Staphylococcus xylosus, and Achromobacter xylosoxidans are among the bacteria that have been identified. The most effective extract was R. graveolens, followed by P. harmala and C. colocynthis, according to the results of antibacterial activity using the disc diffusion method. R. graveolens extract had the lowest MIC values (less than 2 mg/mL) against all microorganisms tested. This shows that the R. graveolens extract has additional properties, such as the ability to be both scolocidal and bactericidal. Because these bacteria are among the most prevalent pathogenic bacteria that increase the risk of secondary infection during hydatid cysts, the results of inhibitory zones and MICs of the R. graveolens methanol extract are considered highly promising.

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.

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

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

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

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