An abattoir-based study on the prevalence and economic losses due to cystic echinococcosis in slaughtered herbivores in Ahwaz, south-western Iran

Epidemiological study on bovine cystic echinococcosis: Abattoir survey, cyst characterization and its economic impact at Mekaneyesuse municipality abattoir, Northwest Ethiopia

Cystic echinococcosis (CE) is a major medical and veterinary concern in the world. It is one of the significant diseases in livestock farming communities managed under extensive grazing system like Ethiopia. Domestic intermediate hosts are an important reservoir for the disease spread. A cross-sectional study was conducted to determine the occurrence and economic losses associated with CE in cattle slaughtered at Mekaneyesuse Municipality abattoir, South Gondor zone of Amhara Region, North West Ethiopia. Ante-mortem inspection, postmortem examinations of organs, hydatid cyst characterization and financial loss estimations were conducted. The study was conducted on 384 cattle. The involvement of different organs was as follows: lungs (46.09%), liver (45.22%), heart (6.09%), and kidneys (2.6%). Out of the total of 115 cysts observed, small cysts constituted 57.39%, medium-sized were 34.78%, and large cysts accounted for 7.83%. Of these 115 cysts, 53.9% were fertile which included both viable (29%) and non-viable (71%) cysts. Furthermore, 46.1% cysts were non fertile, 62.3% were sterile and 37.7% were calcified. Based on the origin of animal, the prevalence of hydatid cysts was recorded to be 31.25%, 24%, 22.05% and 14.25% in Tachgayent, Semada, Andabet and Estie district, respectively. Higher cyst occurrence was observed in animals with poor body condition (51.56%) followed by medium (13.7%) and good body condition scores (8.25%). The total annual economic loss due to the direct condemnation of organs and indirect losses were estimated to be 851,252.68 ETB ($16,061.06). This study revealed that CE is economically important disease at Mekaneyesuse, South Gondar Zone, Amhara Region, Northwest Ethiopia. A more comprehensive investigation is required on prevalence and genotyping of Echinococcus granulosus s.l. cysts is important also to identify and estimate the relative contribution of each species or genotype to the disease in this area. Moreover, efforts to enhance public awareness in the area should also be pursued.

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.

IEg67 kDa Bovine Hydatid Cyst Antigen: A Candidate for Developing Sero-Diagnostic Assays for Cystic Echinococcosis, a Disease of One Health Importance

Cystic echinococcosis (hydatidosis) is a world-wide zoonotic disease of mainly humans, livestock and dogs, caused by Echinococcus granulosus. The disease can negatively impact food production and animal welfare and causes socio-economic hardship. Here, we aimed to identify the local bovine hydatid cyst fluid (BHCF) antigen for developing a sero-diagnostic assay to be used for the pre-slaughter screening of food animals. In total, 264 bovines approved for slaughter in Pakistan were subjected to serum collection and post-mortem screening for hydatid cysts. These cysts were assessed microscopically to assess fertility and viability, and by PCR for molecular confirmation of species. A BHCF antigen was identified from positive sera via SDS-PAGE, confirmed by Western blot, and quantified via a bicinchoninic acid (BCA) assay. The quantified crude BHCF antigen (iEg67 kDa) was then used in ELISA screening to test all sera collected from known positive and negative animals based on hydatid cyst presence/absence. Of the 264 bovines examined, 38 (14.4%) showed hydatid cysts during post-mortem examination. All of these individuals, plus an additional 14 (total: 52; 19.6%) tested positive based on less time-consuming ELISA examination. Based on ELISA, occurrence in females (18.8%) was significantly higher than in males (9.2%) and was higher in cattle (19.5%) compared to buffalo (9.5%). The infection rate increased with age in both host species: cumulatively, 3.6% in animals aged 2-3 years, 14.6% in 4-5-year-olds and 25.6% in 6-7-year-olds. The occurrence of cysts in cattle was significantly higher in the lungs (14.1%) compared to their livers (5.5%), whereas the opposite was true in buffalo (6.6% livers, 2.9% lungs). For both host species, most cysts in the lungs were fertile (65%), while the majority in the liver were sterile (71.4%). We conclude that the identified iEg67 kDa antigen is a strong candidate for the development of a sero-diagnostic screening assay for the pre-slaughter diagnosis of hydatidosis.

The occurrence of cystic echinococcosis in slaughtered livestock in Jahrom, south of Iran

Cystic echincoccosis (CE) is a major medical and veterinary concern in the world, especially in Iran. Domestic intermediate hosts are an important reservoir for the disease spread. The purpose of this study was to determine the prevalence of CE in slaughtered livestock in Jahrom, south of Iran. In this cross-sectional study, a total of 3074 animals (2325 (75.63%) goats, 423 (13.76%) sheep, and 326 (10.60%) cattle) were inspected macroscopically for CE. In this regard, a questionnaire about the age, sex, infected organ, number of cysts, and cyst fertility was accomplished for each animal. Moreover, PCR was applied by using the cytochrome c oxidase I (COX1) and NADH dehydrogenase subunit 1 (nad1) fragments of parasite mitochondrial genomes on some positive samples. Prevalence of CE in sheep, cattle, and goats was 11.34% (48/423), 11.04% (36/326), and 2.79% (65/2325), respectively. In all livestock, CE was more common in females than males. Moreover, the highest infection rate was observed in the age group of more than 72 months. Considering the fertility of cysts, the ratio of the number of fertile cysts to total cysts in sheep and goats were 83.3% (40/48) and 80% (52/65), respectively. All hydatid cysts were infertile in cattle. With regard to the location of the cyst on internal organs, the most were observed in the lungs and liver. Regarding the intensity of infection, 1–5, 6–9 and ≥ 10 cysts were detected in 78.52% (117/149), 6.71% (10/149) and 10.73% (16/149) of infected livestock, respectively. In all livestock, hydatid cyst with a diameter of 1–5 cm was the most frequent with 71.81% (107/149). All 149 cyst samples were subjected to PCR. Among them, a total of 18 samples (six samples of each animal) were prepared for sequencing. G6 was the most dominant. According to the results of present study and the relatively high prevalence of CE in slaughtered livestock in Jahrom, health policy makers, health authorities, and experts should make effective approach in this regard, and implement careful inspections.

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.

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.

Prevalence and Molecular Characterization of Cystic Echinococcosis in Livestock Population of the Malakand Division, Khyber Pakhtunkhwa, Pakistan

Cystic echinococcosis (CE) is a neglected zoonotic disease prevalent in Pakistan, but the genetic diversity of the cestode is largely unexplored in the country. This study investigated the molecular epidemiology of CE infecting the livestock population of the Malakand division, Khyber Pakhtunkhwa, Pakistan. A total of 1,200 livestock, including buffaloes, cattle, goats, and sheep, were examined for echinococcosis from November 2017-2018 at different slaughterhouses in the Malakand division. Hydatid cysts were collected from different organs, and hydatid cyst fluid (HCF) was examined microscopically and used for DNA extraction. The LSU (rrnl) and NAD1 genes were amplified and sequenced. The overall prevalence of CE was 17% (204/1,200), including cows (21.7%), buffaloes (17.4%), goats (10%), and sheep (9.6%). The infection was relatively more prevalent among males (17%) than females (16.9%) and animals of older age (>5 years) (p = 0.710). Liver (63.2%) and lungs (25%) were more affected as compared to kidneys (6.8%) and heart (4.9%). HCF analysis indicated that 52.0% of the cysts were sterile and (48.0%) were fertile. Sequencing and phylogenetic analyses confirmed 80.0% of the isolates as Echinococcus granulosus sensu stricto (G1-G3) in all animal species, while Echinococcus equinus (G4) and Echinococcus ortleppi (G5) were present in buffaloes. The present study concluded that CE is prevalent in the livestock population of Malakand. Besides E. granulosus s. s. (G1-G3), E. ortleppi genotype (G5) and E. equinus (G4) in livestock were also reported.

Echinococcoses in Iran, Turkey, and Pakistan: Old Diseases in the New Millennium

Echinococcosis is considered a cosmopolitan zoonosis caused by different species of small taeniid tapeworms of the genus Echinococcus and is regarded as a neglected zoonosis. Cystic and alveolar echinococcoses are endemic diseases of Tibetan, Pamir, and Iranian plateaus. All of the countries within the Iranian plateau are affected by echinococcosis. Pakistan, Turkey, and Iran are the three most populous countries of the region, in which echinococcosis is highly endemic. The three neighboring countries share strong cultural and socioeconomic ties. The present study aimed to provide a broad review of the status of cystic and alveolar echinococcosis, summarizing the current knowledge about geographical distribution, molecular epidemiology, and transmission dynamics of Echinococcus granulosus sensu lato and Echinococcus multilocularis in this region. Additionally, we aimed to understand disease burden and risk factors as basic requirements for establishing a surveillance system and planning prevention and control programs. A considerable body of information is available on different aspects of echinococcosis in this region; however, several information and research gaps need to be filled before planning control programs. None of the countries in the region have an elaborate echinococcosis control program. Effective control programs require multi/intersectoral coordination within a One Health approach with a long-term political and administrative commitment and enhanced international collaboration among the three countries.

Prevalence of cystic echinococcosis in slaughtered livestock in Iran: a systematic review and meta-analysis

BACKGROUND

Hydatidosis is a zoonotic disease and has a great general and economic health importance in both developed and developing countries. Therefore, this systematic and meta-analytic study was conducted to determine the prevalence of cystic echinococcosis in slaughtered livestock in Iran.

METHODS

The present study was conducted as a systematic review and meta-analysis. The SID & Magiran, MEDLINE (PubMed), ScienceDirect, Scopus, and Google Scholar databases were searched with a view to selecting relevant research works. As a result, 31 articles published from April 1970 to April 2020 were selected. The heterogeneity of the studies was assessed using the I² index. Data analysis was conducted within the Comprehensive Meta-Analysis software (CMA) v.3.0 (Biostat, Englewood, NJ, USA) and Arc map (ArcGIS 10.3) software.

RESULTS

The heterogeneity of the studies was evaluated using the I² test which value was 99% showing a high heterogeneity in the studies. The results of publication bias in studies were evaluated by the Egger test, which were not statistically significant (P = 0.144). The overall prevalence of cystic echinococcosis in slaughtered livestock in Iran is 13.9% (95%CI: 10.7-17.7%). The results of the meta-regression analysis indicate the increasing trend of the hydatid cyst prevalence with the increase of sample size and publication year (P < 0.05).

CONCLUSION

According to the results of this study and the relatively high prevalence of cystic echinococcosis in slaughtered livestock in Iran, health policy makers should make effective decisions in this regard, and implement careful inspections and interventions by experts and health authorities.

Parasitic causes of organ condemnation in cattle slaughtered in Fako abattoirs, South-West region of Cameroon, and estimate of financial losses

An abattoir study was carried out between May and October 2016 to determine the parasitic causes of organ condemnation during meat inspection and to evaluate the attendant financial losses in Fako abattoirs, in the South-West region of Cameroon. Organs (liver, lungs, heart, tongue, kidney, spleen and intestine) were examined at meat inspection following standard procedures and the financial loss was estimated by considering the total weight of condemned organs and the price per kilogram of marketable organs, obtained from the local market. The organs of 1472 cattle were examined, of which 357 (24.38%) were condemned. The organs condemned because of parasitic infestations were the liver (333) and small intestine (24), and the infections were caused by flukes of Fasciola sp. and proglottids of Moniezia sp., respectively. Hydatid cysts and cysticerci were absent. The prevalence of fasciolosis and monieziosis was 22.62% and 1.63%, respectively. Condemnation deprived the region of 665.457 kg of meat, with an associated financial loss of CFA 1,330,902 (USD 2505), during the study period. Parasitic diseases worsen the food insecurity situation as they result in the withdrawal of a considerable amount of meat from the food chain. Fasciolosis, the leading parasitic cause of meat condemnation in Fako, is also zoonotic. It is therefore important that effective control measures are implemented countrywide against this parasitosis.

Cystic echinococcosis in marketed offal of sheep in Basrah, Iraq: Abattoir-based survey and a probabilistic model estimation of the direct economic losses due to hydatid cyst

Cystic echinococcosis (CE) is a highly endemic parasitic zoonosis in Iraq with substantial impacts on livestock productivity and human health. The objectives of this study were to study the abattoir-based occurrence of CE in marketed offal of sheep in Basrah province, Iraq, and to estimate, using a probabilistic modelling approach, the direct economic losses due to hydatid cysts. Based on detailed visual meat inspection, results from an active abattoir survey in this study revealed detection of hydatid cysts in 7.3% (95% CI: 5.4; 9.6) of 631 examined sheep carcasses. Post-mortem lesions of hydatid cyst were concurrently present in livers and lungs of more than half (54.3% (25/46)) of the positive sheep. Direct economic losses due to hydatid cysts in marketed offal were estimated using data from government reports, the one abattoir survey completed in this study, and expert opinions of local veterinarians and butchers. A Monte-Carlo simulation model was developed in a spreadsheet utilizing Latin Hypercube sampling to account for uncertainty in the input parameters. The model estimated that the average annual economic losses associated with hydatid cysts in the liver and lungs of sheep marketed for human consumption in Basrah to be US$72,470 (90% Confidence Interval (CI); ±11,302). The mean proportion of annual losses in meat products value (carcasses and offal) due to hydatid cysts in the liver and lungs of sheep marketed in Basrah province was estimated as 0.42% (90% CI; ±0.21). These estimates suggest that CE is responsible for considerable livestock-associated monetary losses in the south of Iraq. These findings can be used to inform different regional CE control program options in Iraq.

Prevalence of ovine cystic echinococcosis in Kashmir Valley, North India

A total of 1455 local and non-local (originating from other Indian states), slaughtered or spontaneously dead, sheep in various areas of Kashmir Valley were investigated for the presence of cystic echinococcosis over a period of one year. The overall prevalence was 7.97% with higher prevalence in local (14.3%) than in non-local sheep (6.06%). The prevalence of infection, total number of cysts recovered and mean intensity of infection were higher in lungs as 66.2%, 506 & 5.1% respectively, followed by liver (28.5%, 169, 3.9%) and spleen (5.3%, 9, 1.13%). Either single (71.55%) or multiple (28.45%) organ involvements were observed. 66.6% of cysts were of small size, 19.29% medium, 7.01% large and 7.01% calcified. The fertility of cysts was noted to be 65.7% whereas 34.2% were infertile which included 27.1% sterile and 7.01% calcified cysts. The viability percentage of protoscolices from all the fertile cysts was 74.2%. The number of cysts recovered was higher in sheep with body condition score- emaciated, thin and average, and lower in, fat and obesed. The study showed that the local sheep were more vulnerable to contract cystic echinococcosis than non-local sheep which is further aggravated by poor body condition.

Prevalence of echinococcosis and Taenia hydatigena cysticercosis in slaughtered small ruminants at the livestock-wildlife interface areas of Ngorongoro, Tanzania

Aim:

Echinococcosis or hydatidosis (due to the larval stage of Echinococcus spp.) and cysticercosis (due to the larval stage of Taenia hydatigena) pose a significant economic losses due to slaughter condemnation and risk to public health in developing countries such as Tanzania where sanitation is poor and people live in close proximity with each other and with animals. This study was conducted to determine the prevalence of and to identify the predisposing factors for echinococcosis and cysticercosis in sheep and goats at three slaughter slabs located in the livestock-wildlife interface areas of Ngorongoro, Tanzania.

Materials and Methods:

A cross-sectional based survey was conducted, from January 2013 to April 2013, whereby a total of 180 animals comprising 90 goats and 90 sheep of both sexes were examined at postmortem for the evidence of larval stages of Echinococcus spp. (hydatid cyst) and T. hydatigena (Cysticercus tenuicollis) through visual inspection, incision and palpation of organs and viscera.

Results:

The prevalence of echinococcosis was 22.2% and 16.6%, in goats and sheep, respectively, while the overall infection rates for cysticercosis were 61.1% in goats and 42.2% in sheep. The result of this study revealed that goats and sheep in Malambo slaughter slab had significantly higher prevalence of T. hydatigena (C. tenuicollis) and hydatid cysts (p<0.05) compared to other slab points. T. hydatigena (C. tenuicollis) cysts were more frequently detected in the omentum than other visceral organs among the animals examined.

Conclusion:

In conclusion, the observed high prevalence of the two metacestodes larval stages leads to high condemnation rates of edible offals and raises significant public health concerns. This underscores for the need to undertake more extensive epidemiological investigations to better determine the causal factors, economic impact, and public health importance of the disease in this livestock-wildlife interface setting.

The Echinococcoses: Diagnosis, Clinical Management and Burden of Disease

The echinococcoses are chronic, parasitic diseases that are acquired after ingestion of infective taeniid tapeworm eggs from certain species of the genus Echinococcus. Cystic echinococcosis (CE) occurs worldwide, whereas, alveolar echinococcosis (AE) is restricted to the northern hemisphere, and neotropical echinococcosis (NE) has only been identified in Central and South America. Clinical manifestations and disease courses vary profoundly for the different species of Echinococcus. CE presents as small to large cysts, and has commonly been referred to as 'hydatid disease', or 'hydatidosis'. A structured stage-specific approach to CE management, based on the World Health Organization (WHO) ultrasound classification of liver cysts, is now recommended. Management options include percutaneous sterilization techniques, surgery, drug treatment, a 'watch-and-wait' approach or combinations thereof. In contrast, clinical manifestations associated with AE resemble those of a 'malignant', silently-progressing liver disease, with local tissue infiltration and metastases. Structured care is important for AE management and includes WHO staging, drug therapy and long-term follow-up for at least a decade. NE presents as polycystic or unicystic disease. Clinical characteristics resemble those of AE, and management needs to be structured accordingly. However, to date, only a few hundreds of cases have been reported in the literature. The echinococcoses are often expensive and complicated to treat, and prospective clinical studies are needed to better inform case management decisions.

Global Distribution of Alveolar and Cystic Echinococcosis

Alveolar echinococcosis (AE) and cystic echinococcosis (CE) are severe helminthic zoonoses. Echinococcus multilocularis (causative agent of AE) is widely distributed in the northern hemisphere where it is typically maintained in a wild animal cycle including canids as definitive hosts and rodents as intermediate hosts. The species Echinococcus granulosus, Echinococcus ortleppi, Echinococcus canadensis and Echinococcus intermedius are the causative agents of CE with a worldwide distribution and a highly variable human disease burden in the different endemic areas depending upon human behavioural risk factors, the diversity and ecology of animal host assemblages and the genetic diversity within Echinococcus species which differ in their zoonotic potential and pathogenicity. Both AE and CE are regarded as neglected zoonoses, with a higher overall burden of disease for CE due to its global distribution and high regional prevalence, but a higher pathogenicity and case fatality rate for AE, especially in Asia. Over the past two decades, numerous studies have addressed the epidemiology and distribution of these Echinococcus species worldwide, resulting in better-defined boundaries of the endemic areas. This chapter presents the global distribution of Echinococcus species and human AE and CE in maps and summarizes the global data on host assemblages, transmission, prevalence in animal definitive hosts, incidence in people and molecular epidemiology.

Cystic echinococcosis amongst small ruminants and humans in central Ethiopia

This study was conducted to determine the prevalence of cystic echinococcosis (CE) in small ruminants and humans in Addis Ababa, central Ethiopia. A cross-sectional study involving systematic random sampling was conducted to estimate the prevalence of CE in 512 small ruminants (262 sheep and 250 goats) slaughtered at Addis Ababa Abattoir Enterprise between October 2011 and March 2012. Hydatid cysts were identified macroscopically during postmortem examination and their fertility and viability were determined. CE was observed in 21 (8.02%) sheep and 17 (6.80%) goats. In sheep 13 (4.96%) of the lungs, 10 (3.81%) livers and 1 (0.381%) heart were found to be infected with hydatid cysts. Involvement of lung and liver in goats was found to be 10 (4.0%) and 8 (3.2%) respectively, with no cysts recorded in the heart. Of the total of 77 and 47 cysts encountered in sheep and goats, 33 (42.85%) and 15 (31.91%) respectively were fertile. Viability of protoscoleces from fertile cysts in sheep (29 [87.87%]) was higher than in goats (6 [40.0%]). For humans, retrospective analysis covering five years of case reports at two major hospitals in Addis Ababa between January 2008 and December 2012 showed that of the total of 25 840 patients admitted for ultrasound examination, 27 CE cases were registered, a prevalence of 0.1% and mean annual incidence rate of approximately 0.18 cases per 100 000 population. Liver was the major organ affected in humans (81.5% in affected patients) followed by spleen (11.1%) and kidney (7.4%). Logistic regression analysis showed that prevalence of CE varied significantly in relation to host age in the small ruminants (OR = 3.93, P < 0.05) as well as in humans (95% CI, R = 4.8). This epidemiological study confirms the importance of CE in small ruminants and humans in central Ethiopia, emphasising the need for integrated approaches to controlling this neglected preventable disease.

Epidemiological Investigations on Cystic Echinococcosis in North-West (Sidi Kacem Province) Morocco: Infection in Ruminants

Despite alarming statistics on cystic echinococcosis (CE) in humans and the importance of dog and ruminant populations, no epidemiological investigations have been performed on CE in Sidi Kacem Province (North-West of Morocco). A part of large research project was devoted to determine the status of CE in ruminants. This paper reports the results of the investigations carried out in the 10 abattoirs of this region, over four successive years (April 2009–March 2013). A total of 1,302 sheep, 652 head of cattle, and 136 goats were postmortem examined and hydatid cysts were collected and examined. The overall CE prevalence of infection was 42.9% in cattle, 11.0% in sheep, and 1.5% in goats. The prevalence shows significant association with age in sheep and cattle; sheep above 3 years and cattle above 5 years are highly infected (64.0% and 72.2%, resp.). Only liver and lungs are found to be infected. Molecular analyses identified G1, G2, and G3 of E. granulosus sensu stricto in liver and lung samples. Cyst fertility was significantly higher in sheep (54.9%) than in cattle (50.3%). These findings suggest that control measures should target not only sheep but also cattle.

Lateral flow test using Echinococcus granulosus native antigen B and comparison of IgG and IgG4 dipsticks for detection of human cystic echinococcosis

Cystic echinococcosis (CE) caused by infection with Echinococcus granulosus is of major concern for humans in many parts of the world. Antigen B was prepared from E. granulosus hydatid fluid, and Western blots confirmed eight batches showing a band corresponding to the 8-/12-kDa subunit with positive serum and no low-molecular mass band (< 15 kDa) with negative serum. The batches were pooled and used to prepare lateral flow immunoglobulin G4 (IgG4) and IgG dipsticks. Diagnostic sensitivity was determined using serum samples from 21 hydatidosis patients, and diagnostic specificity was established using sera from 17 individuals infected with other parasites and 15 healthy people. IgG4 dipstick had a diagnostic sensitivity of 95% (20 of 21) and a specificity of 100% (32 of 32). The IgG dipstick had a sensitivity of 100% (21 of 21) and a specificity of 87.5% (28 of 32). Thus, both IgG and IgG4 dipsticks had high sensitivities, but IgG4 had greater specificity for the diagnosis of human CE.

A retrospective survey of hydatidosis based on abattoir data in Kermanshah, Iran from 2008 to 2013

A retrospective study was carried out from 2008 to 2013 to estimate the prevalence of hydatidosis in ruminants slaughtered at the Kermanshah municipal abattoir, in western Iran. A total number of 663,633 livestock (393,585 sheep, 81,080 goats and 188,968 cattle) slaughtered in the 5-year period and overall 9,524 (1.43 %) livers and 13,147 (1.98 %) lungs were condemned. The lungs were more frequently infected with hydatid cysts than the livers in all animal species. The average prevalence of hydatidosis was 2.7 % in this area. The prevalence of Echinococcus granulosus infection recorded in the present study was generally lower than those reported from other regions of Iran. Greater awareness among farmers, destruction of organs containing hydatid cysts, prevention of access of dogs to raw offals and implementation of national rabies control program could be responsible factors. The results showed a significant difference (p < 0.001) in the prevalence of hydatidosis among studied animals with higher prevalence in cattle than sheep, with the lowest prevalence recorded in goats. However the annual prevalence of liver and lung condemnations due to hydatidosis was decreased in some years, but the overall trend had a variable pattern in the prevalence of hydatidosis over the study period. Data showed a significant seasonal pattern for hydatidosis in all studied animals. Liver and lung condemnations due to hydatidosis were higher in the fall for sheep and cattle, whereas in goats were higher in summer. This could be attributed to various factors such as sources of slaughtered animals, changes in management practice and ecological factors. The current results suggest that a systematic investigation that lead to a disease control strategy is required to reduce the economic and public health consequences of hydatidosis. In addition, the present survey provides baseline data for the future monitoring of this potentially important parasitic disease in the region.

Survey of hydatidosis infection in slaughtered camel (Camelus dromedarius) in Tabriz area, Northwest Iran

Hydatid Disease is the name given to the condition caused by the zoonotic tapeworm Echinococcus granulosus. The tapeworm spends most of its adult life in the intestine of its definitive host, namely canids and in particular the dog. The tapeworm eggs become voided in the canids' faeces and as a result of ingesting the eggs, infection passes to the intermediate host, commonly herbivores while grazing. However, humans can become accidentally infected and hydatid cysts may develop throughout the body. During April 2010-February 2014, a total 198 camels, which had been sent to the abattoir, the daily number of hydatid infected livers and lungs of camels slaughtered at Tabriz abattoir were recorded. To be sure about the validity of recorded data, observed data were collected daily. Approximately 29 (14.64 %) of camels were infected according to this survey. Age wise, the prevalence of infection in young animals (under the age of 5 years) was 4 (2.02 %), whereas in animals between 5 and 10 years and over, the prevalence of infection was 11 (5.55 %) and 14 (7.07 %) respectively. Sex wise, female animals had a higher prevalence with 17 (19.76 %) cases in camels, whereas in the males, there were 12 (10.71 %) cases in camels. There was a notable difference found in our study between male and female animals (P < 0.05). Infections were recorded in two visceral organs with the Lungs having the highest prevalence in camels, and the liver had low infected in camels. The results of this study suggest that infection of camels with hydatid cyst is common in Tabriz, Iran and that this may constitute economic and health problems in the meat industry.

Hydatidosis in goats in Jammu, India

The prevalence of hydatidosis was carried out in slaughtered goats (n = 177) by liver and lung examination at Jammu. The prevalence rate of hydatidosis was 19.8 %. A total of 14.1 % goats had cysts in both the livers and lungs while 2.3 and 3.4 % goats had cysts in the livers or lungs, respectively. A total of 9.1 % goats had fertile cysts. The adult goats (>4 years) had a significantly higher (p = 0.01) prevalence rate as compared to the young goats (<2 years). Sex had no significant effect on the prevalence of hydatidosis in goats. The histopathological section of the affected lungs revealed a thick coat of granulation tissue causing fibrosis. The cysts caused progressive focal pressure atrophic lesions at the sites of predilection, resulting in atelectasis, desquamation of bronchial epithelium and interalveolar haemorrhages. It may be concluded that the slaughter of food animals at an early age would help to reduce the infection prevalence in dogs and subsequently in the food animals.

The monetary burden of cystic echinococcosis in Iran

Cystic echinococcosis (CE) is a globally distributed parasitic infection of humans and livestock. The disease is of significant medical and economic importance in many developing countries, including Iran. However, the socioeconomic impact of the disease, in most endemic countries, is not fully understood. The purpose of the present study was to determine the monetary burden of CE in Iran. Epidemiological data, including prevalence and incidence of CE in humans and animals, were obtained from regional hospitals, the scientific literature, and official government reports. Economic data relating to human and animal disease, including cost of treatment, productivity losses, and livestock production losses were obtained from official national and international datasets. Monte Carlo simulation methods were used to represent uncertainty in input parameters. Mean number of surgical CE cases per year for 2000-2009 was estimated at 1,295. The number of asymptomatic individuals living in the country was estimated at 635,232 (95% Credible Interval, CI 149,466-1,120,998). The overall annual cost of CE in Iran was estimated at US$232.3 million (95% CI US$103.1-397.8 million), including both direct and indirect costs. The cost associated with human CE was estimated at US$93.39 million (95% CI US$6.1-222.7 million) and the annual cost associated with CE in livestock was estimated at US$132 million (95% CI US$61.8-246.5 million). The cost per surgical human case was estimated at US$1,539. CE has a considerable economic impact on Iran, with the cost of the disease approximated at 0.03% of the country's gross domestic product. Establishment of a CE surveillance system and implementation of a control program are necessary to reduce the economic burden of CE on the country. Cost-benefit analysis of different control programs is recommended, incorporating present knowledge of the economic losses due to CE in Iran.

Direct interaction between EgFABP1, a fatty acid binding protein from Echinococcus granulosus, and phospholipid membranes

Background

Growth and maintenance of hydatid cysts produced by Echinococcus granulosus have a high requirement for host lipids for biosynthetic processes, membrane building and possibly cellular and developmental signalling. This requires a high degree of lipid trafficking facilitated by lipid transporter proteins. Members of the fatty acid binding protein (FABP) family have been identified in Echinococcus granulosus, one of which, EgFABP1 is expressed at the tegumental level in the protoscoleces, but it has also been described in both hydatid cyst fluid and secretions of protoscoleces. In spite of a considerable amount of structural and biophysical information on the FABPs in general, their specific functions remain mysterious.

Methodology/Principal Findings

We have investigated the way in which EgFABP1 may interact with membranes using a variety of fluorescence-based techniques and artificial small unilamellar vesicles. We first found that bacterial recombinant EgFABP1 is loaded with fatty acids from the synthesising bacteria, and that fatty acid binding increases its resistance to proteinases, possibly due to subtle conformational changes induced on EgFABP1. By manipulating the composition of lipid vesicles and the ionic environment, we found that EgFABP1 interacts with membranes in a direct contact, collisional, manner to exchange ligand, involving both ionic and hydrophobic interactions. Moreover, we observed that the protein can compete with cytochrome c for association with the surface of small unilamellar vesicles (SUVs).

Conclusions/Significance

This work constitutes a first approach to the understanding of protein-membrane interactions of EgFABP1. The results suggest that this protein may be actively involved in the exchange and transport of fatty acids between different membranes and cellular compartments within the parasite.

Echinococcus granulosus is the causative agent of hydatidosis, a zoonotic infection that affects humans and livestock, representing a public health and economic burden in many countries. Since the parasites are unable to synthesise most of their lipids de novo, they must acquire them from the host and then deliver them by carrier proteins to specific destinations. E. granulosus produces in abundance proteins of the fatty acid binding protein (FABP) family, one of which, EgFABP1 has been characterised at the structural and ligand binding levels, but it has not been studied in terms of the mechanism of its interaction with membranes. We have investigated the lipid transport properties and protein-membrane interaction characteristics of EgFABP1 by applying biophysical techniques. We found that EgFABP1 interacts with membranes by a mechanism which involves direct contact with them to exchange their cargo. Given that the protein has been found in the secretions of the parasite, the implications of its direct interactions with host membranes should be considered.

An abattoir-based study on the prevalence of hydatidosis in livestock in Mashhad, Iran

A 6-year (2004–2010) retrospective study was carried out to determine the prevalence of hydatidosis in livestock slaughtered in Mashhad abattoir, Mashhad, in north-eastern Iran and the capital of Khorasan province. Between 20 March 2004 and 19 March 2010, 5,131,485 animals (411,163 cattle; 4,547,618 sheep; 172,704 goats) were slaughtered in the study area and 388,399 (7.5%) livers and 1,139,529 (22.2%) lungs were discarded. Hydatidosis was responsible for 4% and 6.5% of total livers and lungs inspected, respectively. Of the cattle livers and lungs inspected over the survey period, 5.5% and 7.9% were condemned, respectively, because they held hydatid cysts. The corresponding values for livers and lungs of sheep (2%, 4%) and of goats (4.5%, 7.8%), respectively, were also condemned due to hydatidosis. Data showed a prominent seasonal pattern for hydatidosis. Liver condemnations due to hydatidosis were higher in winter and autumn for cattle and sheep, respectively, whereas lung condemnations were higher in summer for sheep and cattle. In goats, liver and lung condemnations were higher in winter. This could be attributed to various factors, such as sources of slaughtered animals, changes in management practice and ecological factors. The present survey provides baseline data for the future monitoring of this potentially important parasitic disease in the region.