Prevalence and associated risk factors of hydatidosis in cattle slaughtered at Wolaita Sodo municipality abattoir

BACKGROUND

Hydatidosis, caused by the larval stage of the tapeworm Echinococcus granulosus, affect cattle by forming hydatid cyst in thier lungs, livers and pose great financial loss in animal production and country's economy by both direct and indirect effect. Despite its great economic and health importance, there is an absence of current information on cystic echinococcosis in cattle slaughtered at Wolaita Sodo municipality abattoir in Ethiopia.

OBJECTIVES

Current investigation determines the prevalence, organ distribution and fertility of hydatid cysts in cattle slaughtered at the Wolaita Sodo municipality abattoir in Ethiopia.

METHODS

A cross-sectional study was conducted from February, 2023, to October, 2023, at Wolaita Sodo municipality abattoir in southern Ethiopia, through regular meat examinations and cyst characterisation to determine the prevalence, organ distribution and fertility of hydatid cysts.

RESULTS

The overall prevalence of hydatidosis recorede in current study was 17.9% (69/384) and has shown a statistically significant association (p < 0.05) with the body condition of cattle. However, there was no statistically significant association (p > 0.05) between the prevalence of hydatidosis and other risk factors such as sex, breed, production system and origin of animals. This study showed that the lungs and liver were the most affected organs in cattle, followed by the spleen and kidneys. On cyst characterisation, the majority of hydatid cysts were found sterile (55.4%) followed by fertile (38.8%) and calcified (8.7%) cysts. Out of 125 fertile hydatid cysts tested for survival, 18.8% (58/321) were viable and 20% (67/321) were nonviable.

CONCLUSION

The finding of this study shows that cystic echinococcus was important health threat of the cattle and widespread in the internal organs of affected cattle causing significant economic loss by condemning edible organs that are not suitable for human consumption. Therefore, urgent and integreted preventive action is needed to disrupt the life cycle of cystic echinococcosis to tackle subsequent financial loss and risk of zoonosis to humans in the study area.

Prevalence of cystic echinococcosis among livestock in pastoral and agro-pastoral areas in Uganda

Cystic echinococcosis (CE) remains a significant challenge in Uganda with precise status largely undocumented in most communities. To determine CE prevalence, post-mortem examination was done on 14 937 livestock (5873 goats, 1377 sheep, 3726 zebu cattle and 3054 Ankole cattle) slaughtered in abattoirs in the districts of Moroto in Karamoja region, Kumi in Teso region and Nakasongola and Luwero in Buganda region. The overall CE prevalence was 21.9% in sheep, 15.2% in zebu cattle, 5.5% in goats and 2.1% in Ankole cattle. Moroto district had a higher prevalence of CE than other districts with 31.3% in zebu cattle, sheep 28%, goats 29.1% and (0%) in Ankole cattle. On organ locations, the lungs were the most affected in all livestock in all the study areas. Considering cyst fertility, 33.9, 1.7 and 6.4% of Ankole cattle, sheep and zebu cattle respectively had fertile cysts in the liver while 4.5% of goats and 4% Ankole cattle had fertile cysts in the lungs. In conclusion, CE is widespread and occurs among cattle, sheep and goats in pastoral and agro-pastoral areas in Uganda. Therefore, there is an urgent need to create awareness among the communities on role of livestock in CE epidemiology and transmission.

Genetic diversity and haplotypes of Echinococcus granulosus isolated from cattle and buffaloes and first report of E. ortleppi (G5) in buffaloes in Pakistan based on mitochondrial cytochrome c oxidase subunit-1 gene (mt-CO1) markers

Cystic echinococcosis (CE) is a parasitic disease that is caused by larval stage of Echinococcus granulosus tapeworm, one of the most important and neglected zoonotic disease. Although the echinococcosis is endemic in the neighboring countries, information regarding circulating genotypes of E. granulosus sensu lato is scarce in Pakistan. Therefore, the main purpose of this report was to contribute in molecular epidemiology and to find genetic variation and haplotypes of E. granulosus s.l. in cattle and buffalo isolates. To identify species circulating in country, parasite samples were collected from different slaughterhouses and butcher shops of two major cities, Rawalpindi and Peshawar located in Punjab and Khyber Pakhtunkhwa (KP) provinces, Pakistan, respectively. A total of 100 CE cyst samples were investigated from buffalo (n = 61), and cattle (n = 39) hosts. After genomic DNA extraction from individual cyst materials, mt-CO1 (875 bp) gene was amplified by PCR. After that, PCR products were electrophoresed on the agarose gel then purified and sequenced using forward primer. The sequences were trimmed (779 bp), aligned and matched with NCBI published sequences. E. granulosus s.s. (G1, G3) (71.4%; n = 20/28) was confirmed as the dominant species in buffalo and cattle. E. ortleppi (G5) (28.6%; n = 8/28) was recorded for the first time in both buffalo and cattle isolates from Rawalpindi. E. granulosus s.l. haplotype network showed single predominant haplotype, which comprised 40% of population. Tajima's D and Fu's Fs were negative and significant for E. ortleppi (G5), suggesting population expansion in Pakistan. Therefore, more studies using isolates of E. granulosus s.l. from various locations and intermediate hosts across Pakistan will add new data on molecular epidemiology and genotyping for effective control strategies of CE in Pakistan.

A scoping review of zoonotic parasites and pathogens associated with abattoirs in Eastern Africa and recommendations for abattoirs as disease surveillance sites

Abattoirs are facilities where livestock are slaughtered and are an important aspect in the food production chain. There are several types of abattoirs, which differ in infrastructure and facilities, sanitation and PPE practices, and adherence to regulations. In each abattoir facility, worker exposure to animals and animal products increases their risk of infection from zoonotic pathogens. Backyard abattoirs and slaughter slabs have the highest risk of pathogen transmission because of substandard hygiene practices and minimal infrastructure. These abattoir conditions can often contribute to environmental contamination and may play a significant role in disease outbreaks within communities. To assess further the risk of disease, we conducted a scoping review of parasites and pathogens among livestock and human workers in abattoirs across 13 Eastern African countries, which are hotspots for zoonoses. Our search results (n = 104 articles) showed the presence of bacteria, viruses, fungi, and macroparasites (nematodes, cestodes, etc.) in cattle, goats, sheep, pigs, camels, and poultry. Most articles reported results from cattle, and the most frequent pathogen detected was Mycobacterium bovis, which causes bovine tuberculosis. Some articles included worker survey and questionnaires that suggested how the use of PPE along with proper worker training and safe animal handling practices could reduce disease risk. Based on these findings, we discuss ways to improve abattoir biosafety and increase biosurveillance for disease control and mitigation. Abattoirs are a 'catch all' for pathogens, and by surveying animals at abattoirs, health officials can determine which diseases are prevalent in different regions and which pathogens are most likely transmitted from wildlife to livestock. We suggest a regional approach to biosurveillance, which will improve testing and data gathering for enhanced disease risk mapping and forecasting. Next generation sequencing will be key in identifying a wide range of pathogens, rather than a targeted approach.

From farm to table: exploring food handling and hygiene practices of meat and milk value chain actors in Ethiopia

Livestock value chains constitute a source of livelihood for meat and milk value chain actors in Ethiopia, from dairy farmers to other associated value chain actors such as milk traders, abattoir workers, public health officials, veterinarians, butcheries selling meats, milk cooperatives, artisanal milk processors, and transporters. The development of these livestock value chains, however, is constrained by poor food safety and quality, while consumers are also exposed to public health risks due to milk and meat value chain actors' food handling and hygiene practices.This study used Photovoice and participant observation to explore meat and milk value chain actors' food handling and hygiene practices in suburban areas of Addis Ababa and neighbouring Oromia in Ethiopia. The results of this study reveal that milk and meat value chain actors' food handling practices are not aligned with the recommended Ethiopian food safety and quality standards. Low compliance with food safety and quality standards reflected a combination of factors such as lack of incentives, poor road infrastructure and low enforcement of food safety standards.Participatory and visual research methods enable a researcher to collect context-aware data that can lead to the development of policies and intervention strategies that reflect local needs and priorities. The results of this study affirm the need to identify socially acceptable and economically viable policies and intervention strategies that are acceptable to all chain actors; and suggest there is an imperative to train milk and meat value chain actors on good hygiene handling practices, improve road infrastructure, and facilitate access equipment such as fridges and freezers that can contribute to maintaining food safety and quality.

Cystic echinococcosis in cattle slaughtered at a slaughterhouse in Gessa, southern Ethiopia

Cystic echinococcosis is caused by the metacestode of the zoonotic flatworm Echinococcus granulosus. A cross-sectional study was conducted from October 2020 to August 2021 at the Gessa municipality abattoir in southern Ethiopia, through regular meat examinations and cyst characterization to determine the prevalence, organ distribution, and fertility of Cystic echinococcosis. The overall prevalence of Echinococcus granulosus sensu lato was 17.9% (69/384) and has shown a statistically significant association (p < 0.05) with the body condition of cattle but not with other putative risk factors (p > 0.05). The odds of poor body condition cattle infected with CE was 1.29 times higher than medium body condition (OR = 0.506; CI = 0.566–2.96). Based on organ distribution of cysts, the lungs and liver were the most affected organs having a statistically significant difference (p < 0.05) with the prevalence of CE. Based on the size of cysts, small (47.9%) size cysts revealed the highest prevalence as compared with large (33.3%) and medium (18.8%) sized cysts. On cyst characterization, the majority of Cystic echinococcosis were sterile cysts (55.4%) followed by fertile (38.8%) and calcified (8.7%) cysts and revealed a statistically significant difference (p < 0.05). Cyst number, organ localization, fertility of cyst, and cyst size have shown a strong positive correlation (r = 0.8686, r = 0.8393, r = 0.9506, and r = 0.9189) with the prevalence of CE, respectively. The presence of an overall high prevalence of Echinococcus granulosus sensu lato in the present study required urgent action to interrupt the life cycle of Cystic echinococcosis and further studies using molecular techniques to characterize the circulating genotypes to prevent the risk of zoonosis in humans in the study area.

Cattle co-infection of Echinococcus granulosus and Fasciola hepatica results in a different systemic cytokine profile than single parasite infection

E. granulosus is a cestode that causes Cystic Echinococcosis (CE), a zoonotic disease with worldwide presence. The immune response generated by the host against the metacestode induces a permissive Th2 response, as opposed to pro-inflammatory Th1 response. In this view, mixed Th2 and regulatory responses allow parasite survival. Overall, larval Echinococcus infections induce strong regulatory responses. Fasciola hepatica, another common helminth parasite, represents a major infection in cattle. Co-infection with different parasite species in the same host, polyparasitism, is a common occurrence involving E. granulosus and F. hepatica in cattle. ‘While it is known that infection with F. hepatica also triggers a polarized Th2/Treg immune response, little is reported regarding effects on the systemic immune response of this example of polyparasitism. F. hepatica also triggers immune responses polarized to the Th2/ Treg spectrum. Serum samples from 107 animals were analyzed, and were divided according to their infection status and Echinococcal cysts fertility. Cytokines were measured utilizing a Milliplex Magnetic Bead Panel to detect IFN-γ, IL-1, IL-2, IL-4, IL-6, IL-10, IL-12 and IL-18. Cattle infected only with F. hepatica had the highest concentration of every cytokine analyzed, with both 4.24 and 3.34-fold increases in IL-10 and IL-4, respectively, compared to control animals, followed by E. granulosus and F. hepatica co-infected animals with two-fold increase in IL-10 and IL-4, compared to control animals, suggesting that E. granulosus co-infection dampens the cattle Th2/Treg immune response against F. hepatica. When considering Echinococcal cyst fertility and systemic cytokine concentrations, fertile cysts had higher IFN-γ, IL-6 and IL-18 concentrations, while infertile cysts had higher IL-10 concentrations. These results show that E. granulosus co-infection lowers Th1 and Th2 cytokine serological concentration when compared to F. hepatica infection alone. E. granulosus infections show no difference in IFN-γ, IL-1, IL-2, IL-6 and IL-18 levels compared with control animals, highlighting the immune evasion mechanisms of this cestode.

Prevalence and distribution of Echinococcus spp. in wild and domestic animals across Africa: A systematic review and meta-analysis

Cystic echinococcosis (CE), a worldwide zoonosis, is highly prevalent in Africa particularly in northern and eastern Africa where data are more abundant than other regions. However, harmonization of available data through systematic review and meta-analysis may foster improved transboundary cooperation for the control of CE in Africa. Using the Preferred Reporting Items for Systematic Reviews and Meta-analyses guidelines, research articles (from 2000 to 2019) were retrieved from ScienceDirect, PubMed, African Journals OnLine and Google Scholar databases. A total of 98 studies of 806,624 animals from 13 countries comprising 264,016 goats, 247,326 sheep, 251,106 cattle, 28,314 camels, 4,764 buffaloes, 2,920 equids, 1,966 pigs, 408 wild boars and 50 Norway rats were available for systematic review and meta-analysis of pooled prevalence including 5,048 dogs, 345 lions, 220 hyenas, 94 wolves and 47 jackals/foxes analysed for Echinococcus infection. In total, 46,869 animals were infected and pooled prevalence of CE in intermediate hosts was highest in camels (17.1%; 95% CI: 12.1-22.8) and lowest in pigs (0.3%; 95% CI: 0.1-0.6). Results also showed uneven species/genotype distribution across the continent such that Echinococcus granulosus sensu stricto (G1, G3) constituted 74.45% of the total isolates from East Africa, E. canadensis (G6/7) accounted for 60.3% and 97.4% in North and West Africa, respectively, while 81.3% of E. ortleppi (G5) were recorded for southern Africa. The comparatively higher prevalence estimates for eastern and northern Africa than other regions indicate where efforts on CE management should now be given greater attention in Africa. Additionally, this study also advocates for better cooperation between countries within the same sub-region and the establishment of joint CE control programmes.

Prevalence and monetary loss due to cystic Echinococcosis in slaughter house livestock: A case study of Migori County, Kenya

Cystic Echinococcosis (CE/Hydatidosis) is a parasitic zoonosis of public health importance that causes considerable economic loss worldwide. The aim of this study was to assess prevalence and monetary loss of CE in livestock slaughtered in Migori County, Kenya. The study was conducted by retrieving and analyzing secondary data over a ten year period (2007–2016) from annual meat inspection reports from sub-county veterinary offices within Migori County. The data included species/number of slaughtered animals and number of organs condemned due to presence of hydatid cyst(s) recorded. The results showed CE prevalence was highest in cattle (5.3%) followed by goats (2.0%), least affected were sheep (0.1%). The overall direct monetary loss was $152,003/year. The study results confirm occurrence of CE in Migori County and demonstrate an emerging new CE focus in Kenya with a significant direct monetary loss, a phenomenon that require serious attention to control the spread of CE in Kenya.

Cystic echinococcosis in slaughtered cattle at Addis Ababa Abattoir enterprise, Ethiopia

Cystic echinococcosis, caused by larval stages of the tapeworm Echinococcus granulosus, is responsible for hydatid cysts in the lungs, liver and other organs of intermediate hosts. A cross-sectional Abattoir study was conducted from October 2015 to May 2016 at Addis Ababa Abattoir enterprise, Ethiopia. For this purpose a total of 1209 cattle were examined using the classical meat inspection procedure for the presence of hydatid cysts. An overall prevalence of 21% (254/1209) of hydatid cyst was recorded in cattle slaughtered at Addis Ababa Abattoir enterprise. The prevalence of hydatid cyst was statistically significantly higher (P<0.05) in cattle with the age group of >6 years than those cattle with all other age categories. The study showed that lungs and livers were the most affected organs of cattle. Significantly (P < 0.05) higher overall number of hydatid cysts were observed in the lungs (63.9%; 1324/2071) than in the livers (35.4%; 734/2071). The study revealed the presence of an overall of 84.1% (333/396) sterile, 12.2% (48/396) calcified and 4.3% (17/396) fertile cysts. Of the total of 17 fertile hydatid cysts tested for viability, 17.6% (3/17) viable and 82.3% (14/17) nonviable cysts were observed. Overall, findings of the present study showed the widespread occurrence of hydatid cysts in internal organs of cattle that possibly incur significant economic losses through condemnation of edible organs rendering unfit for human consumption. Molecular studies on the role of intermediate host species, genotypes of E. granulosus, zoonotic impact and economic significance of echinococcosis are needed in different parts of Ethiopia.

Echinococcus granulosus hydatid cyst location is modified by Fasciola hepatica infection in cattle

BACKGROUND

Natural parasite infection occurs in wild and domestics animals with more than one parasite species at the same time, generating an infection called polyparasitism. Cystic echinococcosis reports are usually based only on infection with Echinoccocus granulosus leaving aside other internal parasitoses that could modulate both the immune response and pathogenesis of the natural infection. Fasciola hepatica is another cosmopolitan parasite in ruminants with a similar distribution to E. granulosus in different parts of the world, but no information of the effect of co-infection with E. granulosus has been described. The aims of this report were to establish E. granulosus prevalence and explore the association of F. hepatica co-infection and natural E. granulosus infections in cattle.

RESULTS

From 1725 animals, the prevalence of E. granulosus and F. hepatica was 21.16 and 51.3%, respectively. Considering both infections, older cattle (> 4 years) presented higher prevalence compared to younger animals. In E. granulosus-infected cattle, 5.21% had fertile cysts, 71.78% infertile cysts, and in 23.01% cysts were smaller than 1 cm in diameter. Considering cyst location, 39.72% had lungs cysts, 24.72% had liver cysts and 36.94% had cysts in both organs. Cyst location significantly differed between age groups: 44.68% of younger animals had cysts only in the lungs, while older animals presented hydatid cyst in the lungs and liver simultaneously (44.15%). With E. granulosus infection alone, 30.26% of cysts were found in the lungs, 31.79% in the liver and 37.95% in both organs. Regarding the co-infection of E. granulosus with F. hepatica, the proportion was significantly different (P < 0.05) with most animals having cysts only in the lungs (49.41%) and a lower level of liver infection (15.88%). Analyzing organ cyst distribution and F. hepatica absence/presence ratio within each cyst type, small cysts showed the highest difference in ratio.

CONCLUSIONS

To the best of our knowledge, this is the first report indicating that F. hepatica co-infection in cattle could be affecting the instate of hydatid cysts in the liver, displacing toward lung localization, suggesting an antagonistic relationship.

First description of Echinococcus ortleppi and cystic echinococcosis infection status in Chile

Cystic echinococcosis (CE), a parasitic disease caused by the cestode Echinococcus granulosus sensu lato (s.l.), is a worldwide zoonotic infection. Although endemic in Chile, information on the molecular characteristics of CE in livestock remains scarce. Therefore we aimed to describe the status of infection with E. granulosus s.l. in cattle from central Chile and also to contribute to the study of the molecular epidemiology of this parasite. According to our results, the prevalence of CE is 18.84% in cattle, similar to previous reports from Chile, suggesting that the prevalence in Santiago Metropolitan area has not changed in the last 30 years. Most of the cysts were found only in lungs (51%), followed by concurrent infection in liver and lungs (30%), and only liver (19%). Molecular characterization of the genetic diversity and population structure of E. granulosus s.l. from cattle in central Chile was performed using a section of the cytochrome c oxidase subunit 1 (cox1) mitochondrial gene. E. granulosus sensu stricto (s.s.) (G1-G3 genotypes) was confirmed by RFLP-PCR to be the dominant species affecting cattle (284 samples/290 samples); we also report for the first time in Chile the presence of E. ortleppi (G5 genotype) (2 samples/61 samples). The Chilean E. granulosus s.s. parsimony network displayed 1 main haplotype. Additional studies using isolates from many locations across Chile and different intermediate hosts will provide more data on the molecular structure of E. granulosus s.s. within this region. Likewise, investigations of the importance of E. ortleppi in human infection in Chile deserve future attention.

Characterization of the inflammatory cell infiltrate and expression of costimulatory molecules in chronic echinococcus granulosus infection of the human liver

Background

The local immune responses to chronic echinococcal infections in various organs are largely unknown. Since the liver is the most frequently involved organ in such infections in human we aimed to characterize the inflammatory as well as immune cell infiltrate around hydatid cysts in the liver and compared to common inflammatory processes of the liver.

Method

Surgical samples from the liver of 21 cystic echinococcosis (CE) patients were studied and the distribution of different types of inflammatory and immune cells were determined by immunohistochemistry. Furthermore, expression levels of costimulatory CTLA4, CD28, CD80 and CD86 molecules were measured at RNA level by PCR. Liver biopsy samples from patients with steatohepatitis (SH, n = 11) and chronic hepatitis (CH, n = 11) were used as non-inflammatory and chronic inflammatory controls, respectively. The composition and density of the inflammatory and immune cell infiltrates have been compared by using morphometry.

Results

CD3+ T cells predominated the inflammatory infiltrate in all pathological processes, while in CE samples CD20+ B cells, in CH samples CD68+ macrophages were also frequent. Both myeloperoxidase (MPO) + leukocytes and CD68+ macrophages were found to be significantly decreased in CE as compared to either SH or CH samples. Concerning T cell subtypes, only CD8+ T cells were found to be significantly decreased in SH samples. CD1a + dendritic cells were almost completely missing from CE biopsies unlike in any other sample types. There were no differences detected in the mRNA expression of costimulatory molecules except decreased expression of CD28 in CE samples.

Conclusion

In the hydatid lesions of the liver of chronic echinococcal infections T cell-mediated immunity seems to be impaired as compared to other types of chronic inflammatory processes, suggesting an immunosuppressive role for Echinococcus granulosus, which deserve further attentions.

Bovine IgG subclasses and fertility of Echinococcus granulosus hydatid cysts

Hydatidosis is an important zoonotic disease of worldwide distribution, causing important health problems to humans and major economical losses in infected livestock. Echinococcus granulosus, the etiological agent of hydatid disease, induces a humoral immune response in the intermediate host (human and herbivorous) against hydatid cyst antigens. Specifically, IgGs are found in the laminar and germinal layers and inside the lumen of fertile and infertile hydatid cysts. In the germinal layer of infertile cysts IgGs are found in an order of magnitude greater than in the germinal layer of fertile cysts; a fraction of those IgGs are associated with high affinity to germinal layer proteins, suggesting their binding to specific parasite antigens. We have previously shown that those immunoglobulins, bound with high affinity to the germinal layer of hydatid cysts, induce apoptosis leading to cyst infertility. In the present work the presence of IgG1 and IgG2 subclasses in the germinal layer of both fertile and infertile hydatid cysts is reported. IgG1 is the most relevant immunoglobulin subclass present in the germinal layer of infertile cysts and bound with high affinity to that parasite structure. Contrarily, though the IgG2 subclass was also found in the germinal and adventitial layers, those immunoglobulins show low affinity to parasite antigens. We propose that the binding of an IgG1 subclass to parasite antigens present in the germinal layer is involved in the mechanism of cyst infertility.