Prevalence and economic importance of cystic echinococcosis in slaughtered ruminants in Burdur, Turkey

The Monetary Losses Associated with Hydatidosis in Slaughtered Ruminants in Turkey

Hydatidosis is a parasitic zoonotic disease that negatively affects human and animal health and causes economic losses due to slaughter condemnation and risk to public health in developing countries. This study aims to determine the prevalence of Hydatidosis among slaughtered livestock in different regions of Turkey and calculate the financial losses associated with the zoonosis. For this purpose, livestock slaughter records from the livestock information system in 2020 were considered and direct and indirect economic losses were estimated. The study determined the prevalence of hydatidosis in small ruminants (0.03%) and cattle (0.0124%) and an average of 0.007% of the total number of livestock slaughtered during the period under study were infected with hydatid cysts. The direct and indirect economic losses were estimated at $98.558 and $466.891, respectively. The total monetary loss due to Hydatidosis in Turkey in the year 2020 was estimated at $565.448. In conclusion, significant monetary losses due to Hydatidosis in slaughtered livestock is still an important economic issue to livestock traders in Turkey.

Prevalence and Economic Significance of Hidatidosis in Cattle Slaughtered at an Abattoir in Konya, Turkey

OBJECTIVE

This study was conducted to determine the period prevalence of hydatid cysts isolated from the livers of cattle slaughtered at a slaughterhouse in Konya.

METHODS

For this purpose, 49,545 cattle were slaughtered and examined for the presence of hydatid cysts in the liver. The study was conducted between June 01, 2018, and May 31, 2019.

RESULTS

The highest prevalence of hydatid cysts was observed in autumn 10.83% followed by spring 4.41%, winter 2.90%, and summer 2.66%, with an overall prevalence of 3.93%. Considering the month wise prevalence of hydatid cyst, the highest infection rate was detected in September (7.87%), June (7.16%) and August (7.14%), while the lowest prevalence was observed in February (2.72%) and January (2.83%). In gender-wise investigation, highest prevalence was observed in females (24.65%) during the summer and 18.45% inthe spring. In male animals, the infection rate was very low compared with females. However, the highest prevalence in males was observed throughout the year in autumn (2.36%) and the lowest prevalence in winter (1.68%). The highest prevalence was found among female cattle in heifers in winter (6.52%) and cows in summer (27.52%).

CONCLUSION

The overall economic losses of 56,434 USD were estimated due to discarded hydatid cyst-infected livers during the study period. This study enlightens the prevalence and economic significance of hydatidosis in Konya.

Cystic echinococcosis in slaughtered sheep in Erzurum province, Turkey

Cystic echinococcosis (CE) is an important zoonotic infection caused by the larval stages of the genus Echinococcus. Turkey is a highly endemic region for CE and the disease is one of the major public health problems. The study was aimed to assess the situation of the CE in sheep in Turkey and also to provide data on circulating genotypes in the country. A total of 3319 sheep at slaughter were screened during the study. The prevalence of CE in the study area was 31.7% (1052/3319). The lungs were the most frequently CE infected organ (52.6%, 526/1052). Microscopic examination revealed that overall cyst fertility was 68.1%. Molecular analysis of partial fragments of 12S and COI gene regions were included for 351 selected cyst samples and all of them were identified as E. granulosus sensu stricto. Sequence analysis showed that the predominant genotype in the study areas was G1 (77.1%), and the rest were G3 (22.9%). The prevalence rate of CE in sheep in the study area is lower compared to previous years except for one province. Considering the high cyst fertility rate and the predominance of E. granulosus G1 which is particularly pathogenic to humans, calls for serious control measures like public awareness about the disease, sufficient dog deworming programs, continuity of monitoring the disease should be taken.

Estimating the production losses due to cystic echinococcosis in water buffaloes (Bubalus bubalis) in Turkey

The current study aimed at estimating the direct (condemned offal) and indirect (meat, milk, and fecundity losses) production losses due to cystic echinococcosis (CE) in water buffaloes in Turkey. A spreadsheet loss model was constructed, and the mean prevalence ratio of CE was accepted as 3.8% in male and 21.7% in female buffaloes. The annual financial losses were estimated with official and previously published data under expected (mean value), optimistic (lowered by 10%), and pessimistic (increased by 10%) scenarios with the prices current in 2021. The production losses in an infected male and female water buffalo were estimated at $54.5 ($49.1-59.9) and $89.9 ($80.9-98.9), respectively. Due to CE, the nationwide annual total production losses were estimated at $1.5 million ($1.3-1.6) for water buffaloes in Turkey. In conclusion, farmers, policymakers, and the public need to be informed about CE's risks and financial impact. Control/eradication programs should be included in government policies at the national level after a cost/benefit analysis.

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.

Evaluation of zoonotic platyhelminthe infections identified in slaughtered livestock in Iran, 2015-2019

Background

Platyhelminth infections of livestock can result in considerable economic losses. This study aims to evaluate the spatial frequency of cystic echinococcosis (CE), dicrocoeliasis, and fascioliasis in livestock slaughtered in Iran during the years 2015–2019 and estimate direct costs associated with organ condemnation due to these parasites.

Methods

Abattoir data from 413 abattoirs representing all 31 Iranian provinces were collected from the Iran Veterinary Organization. Infection prevalence was calculated per year at the province level. The Local Moran’s I statistic was performed to evaluate spatial autocorrelation of animals positive at slaughter for the years 2015–2019. Direct costs associated with condemned livers were calculated for each parasitic condition, with costs associated with condemned lungs also included for CE.

Results

Overall prevalence values for the study timeframe were as follows: sheep and goat fascioliasis 1.56% (95% CI: 1.56–1.56%), cattle fascioliasis 3.86% (95% CI: 3.85–3.88%), sheep and goat dicrocoeliasis 4.63% (95% CI: 4.62–4.63%), cattle dicrocoeliasis 3.08% (95% CI: 3.07–3.09%), sheep and goat CE 5.32% (95% CI: 5.32–5.33%), and cattle CE 7.26% (95% CI: 7.24–7.28%). Northwest Iran had the highest prevalence of CE and fascioliasis. High infection areas for Dicrocoelium spp. included the provinces of Zanjan, Gilan, Qazvin, and Tehran, which are located in northern Iran. Direct economic losses for sheep and goat fascioliasis, dicrocoeliasis, and CE for the study period were US$13,842,759, US$41,771,377, and US$22,801,054, respectively. Direct economic losses for cattle fascioliasis, dicrocoeliasis, and CE for the study period were US$1,989,200, US$1,668,986, and US$2,656,568, respectively.

Conclusion

Our findings provide valuable data for future monitoring of these important parasitic diseases in Iranian livestock. Disease control strategies are required to reduce the economic and public health impact of these platyhelminths.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12917-021-02888-9.

Human and animal cystic echinococcosis in Konya, Turkey: molecular identification and the first report of E. equinus from human host in Turkey

Cystic echinococcosis is a neglected, zoonotic disease in Turkey. The disease is commonly seen in rural areas where the local population is in close contact with livestock and dogs. This research aimed to molecularly identify of hydatid cysts in cattle and human isolates from Konya, Turkey. Following sample collection, direct microscopy was performed. After direct examination, total DNA was extracted, and positive PCR products of cox 1 mitochondrial gene (~ 875 bp) were sequenced. A total of 83 hydatid cysts (cattle n = 57 and human n = 26), 82 were identified as Echinococcus granulosus sensu stricto (G1–G3 genotypes), and one human isolate was characterized as Echinococcus equinus (G4 genotype). Fertility rates of cysts belonging to cattle for liver and lung cysts were 93.3% and 80%, respectively. Out of 26 human originated isolates, 18 (69.2%) of cysts were found to be fertile. To the best of our knowledge, this is the first report of E. equinus from human host in Turkey.

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.

The socio-economic burden of cystic echinococcosis in Morocco: A combination of estimation method

Cystic echinococcosis (CE) is a major zoonosis in Morocco despite the launch of a national control programme in 2005. As its economic consequences have not been studied yet in Morocco, this study estimated CE impact in terms of monetary losses, disability-adjusted life years (DALY), and DALY for zoonotic diseases (zDALY) in the entire country and in specific regions for the 2011 to 2014 period. The direct monetary losses were related to organ seizure from infected animal in slaughterhouses, and to healthcare expenses as well as lost wages for infected humans. Animal production losses concerned milk yield, fertility, carcass weight, and wool production. Losses due to human infection were also composed of disability and productivity losses at work. Monte Carlo simulations were used to estimate monetary losses and zDALY values. Nationwide, the estimated DALY was 0.5 years per 100,000 persons per year, and the zDALY was 55 years per 100,000 persons per year. Total yearly losses were estimated at 73 million USD (54–92 million USD). However, losses differed significantly among regions. Most of the economic losses consisted of unperceived consequences, i.e. decreased animal production and reduced productivity of asymptomatic individuals. Future studies should determine the socioeconomic and epidemiological factors underlying the differences in economic losses among regions to develop better adapted control programmes.

Cystic echinococcosis (CE) is a major neglected zoonosis in Morocco, despite the launch of a national control programme in 2005. The first study on CE in Morocco dates back to 1924. However, no evaluation of economic losses was made until now. The present study estimated the economic losses caused by CE in Morocco, at the national and regional scale, by combining financial and non-financial methods. Estimation of the direct and indirect losses caused by CE infection in humans and livestock (sheep, cattle, goats and camels) highlighted the important disease burden nationwide, amounting to 0.07% of Morocco Gross Domestic Product. The combination of methods brought information on the different CE-linked economic losses, including the unperceived consequences. These results indicate that the national CE control strategy did not result in a decrease of the disease burden, which calls for its evaluation and improvement.

Prevalence and economic impact of cystic echinococcosis and liver fluke infections in slaughtered sheep and goat in north-central Iran, 2008-2018

Cystic echinococcosis (CE) and liver fluke infections as important zoonotic infections impose a large socioeconomic impact on societies. As an endemic region for these infections, slaughterhouse inspections should be more considered in Iran. This study aimed to analyze the 11-year record of offal condemnation due to CE, fascioliasis, dicrocoeliasis infections in sheep and goat and its economic impact at Alborz slaughterhouse, north-central Iran. The prevalence rate was calculated as the infected organs (as nominator) divided by the slaughtered cases (as the denominator) in each year and month. The annual percent changes was used to determine trends of parasitic diseases over time. The relationship between metrological indexes and the prevalence of parasitic diseases was determined by the linear regression model. Statistical analyses were done using STATA software 14. For an estimate, the economic impact, the total numbers of offal condemnation were calculated. The overall prevalence rate of fascioliasis, dicrocoeliasis, and CE was 0.95%, 2.17%, and 12.74%, respectively. There was a declining trend in the prevalence of fascioliasis and dicrocoeliasis, whereas, the prevalence of CE increased from 7.57% in 2008 to 9.53% in 2018, representing an annual change of + 0.02%. The direct economic impact was estimated at US$ 1,670,977 and US$ 25,148 for liver and lung, respectively. The number of condemned organs due to these infections is noticeable in Alborz Province, north-central, Iran. The high economic impact of these infections showed the necessity of implementing a continuously infected animal's trace-back and disease control in the site of infection.

Identification of antigen B (AgB) Gene polymorphism in cattle and sheep isolates of Echinococcus granulosus and investigation of effects on serological diagnosis

Cystic Echinococcosis (CE) is a worldwide common helminth disease caused by the larval form of Echinococcus granulosus. The aim of this study is to determine the genetic differences between distinct isolates of E. granulosus obtained from cattle and sheep and determine the polymorphism of the AgB1 gene by DNA sequence analysis, as well as investigating its relationship with serological response using ELISA and Western Blot tests. For this aim, germinal membranes of hydatid cysts of 30 cattle and 30 sheep from the provinces of Elazig and Erzincan in Turkey and serum samples of these animals were collected. Following isolation of the total genomic DNA, the 12S rRNA gene of all isolates was amplified by PCR for genetic characterization, and the mt-CO1 gene region was examined by DNA sequence analysis. The gDNAs were then amplified by PCR using AgB1-specific primers, and genetic variation was investigated by DNA sequence analysis. At the final stage, all serum samples were analyzed by ELISA and Western Blot tests using a partially purified hydatid cyst fluid antigen. As a result, 114 (95%) of the 120 isolates were determined to be E. granulosus sensu stricto by using 12S rRNA-PCR. Subsequently, the DNA sequence analysis of the remaining 6 samples of the mt-CO1 gene revealed that all samples were E. granulosus sensu stricto. According to the DNA sequence analysis that followed, nucleotide changes in the AgB1 gene were observed in 13 (10.8%) of 120 samples. With this study, 9 (69.2%) out of 13 hydatid cysts in which polymorphism was detected by DNA sequence analysis in their AgB1 gene were found to be positive with ELISA, and 6 (46.1%) were found positive by WB. While 80 (74.7%) of 107 non-polymorphic samples in the AgB1 gene were found to be positive with ELISA, and 75 (70.9%) were positive with WB. As a result, variation in different ratios was determined in the AgB1 gene of E. granulosus sensu stricto, and it was determined that this had a partial effect on serological response.

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.

Human cystic echinococcosis in Turkey: a preliminary study on DNA polymorphisms of hydatid cysts removed from confirmed patients

Cystic echinococcosis caused by the larval stages of Echinococcus granulosus sensu lato s.l is endemic in Turkey with a high public health impact particularly in rural areas. The aim of this study was to investigate the genetic variation and population structure of E. granulosus s.s using metacestode isolates removed from surgically confirmed patients originating from several regions in Turkey and to investigate the occurrence of autochthonous transmission. Using DNA extracted from a total of 46 human-derived CE isolates, we successfully analysed an 827-bp fragment within the cox1 mitochondrial gene and confirmed the causative agent of human cystic echinococcosis in patients included in this study to be Echinococcus granulosus s.s (G1 and G3 genotypes). The haplotype parsimony network consisted of 28 haplotypes arranged within three main clusters and the neutrality indices were both negative and significant indicating negative selection or population expansion. The assessment carried out in this study using GenBank nucleotide sequence data from Turkey for sheep and cattle hosts demonstrated the importance of autochthonous transmission with sheep, cattle and humans harbouring the same haplotypes. Further studies are required to investigate the biological significance, if any, of E. granulosus s.s haplotypes and the genetic variability of CE from human patients using longer nucleotide sequences and a larger sample set.

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.

Major causes of organ/carcass condemnation and financial loss estimation in animals slaughtered at two abattoirs in Bursa Province, Turkey

An abattoir survey was conducted from July 2012 to December 2012 to determine the major causes of organ and carcass condemnation and to estimate the associated direct financial loss at two abattoirs in Bursa Province in Turkey. A total of 22,872 sheeps and 5363 cattle were examined by postmortem inspection using standard inspection procedures. The total economic loss in two abattoirs was estimated from the summation of organ and carcass condemnation in six-month period. The retail prices of offal (lung, liver, kidney, heart, and spleen) and kg price of cattle and sheep carcasses were obtained from local markets. The results of postmortem examination indicated that a total of 658 (2.33%) offals and 93 (0.32%) carcasses were condemned. While the main causes of organ condemnation were hydatidosis and fasciolosis, carcasses were condemned mainly due to tuberculosis and jaundice. The total revenue in 2012 for all animals (164,080 sheeps and 56,035 cattle) slaughtered in 15 abattoirs in Bursa Province was 144,401,765 USD. This study showed that financial loss due to organ and carcass condemnations at two abattoirs in six-month period was 245,483 USD (0.17% of the total annual revenue of all slaughtered animals at 15 abattoirs). In sheep, six-month financial loss was estimated at 3281 USD and 4015 USD from organ condemnation due to fasciolosis and hydatidosis, respectively. In cattle, total loss was calculated as 4042 USD and 12,321 USD due to fasciolosis and hydatidosis, respectively. A common cause of carcass condemnation in cattle was tuberculosis, totalling 214,995 USD in losses, whereas condemnation due to tuberculosis was not determined in sheep. The current study also showed that six-month monetary losses from carcass condemnation of sheep and cattle due to jaundice were 8099 USD and 6026 USD, respectively. From the data obtained in this study, it can be concluded that bacterial and parasitic diseases remain common and cause considerable economic loss in Bursa Province, Turkey. The result of this abattoir study provided regional information on major causes of organ and carcass condemnation in sheep and cattle slaughtered at two abattoirs as well as giving an estimation of the direct financial losses.

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.

A systematic review of the epidemiology of echinococcosis in domestic and wild animals

BACKGROUND

Human echinococcosis is a neglected zoonosis caused by parasites of the genus Echinococcus. The most frequent clinical forms of echinococcosis, cystic echinococcosis (CE) and alveolar echinococcosis (AE), are responsible for a substantial health and economic burden, particularly to low-income societies. Quantitative epidemiology can provide important information to improve the understanding of parasite transmission and hence is an important part of efforts to control this disease. The purpose of this review is to give an insight on factors associated with echinococcosis in animal hosts by summarising significant results reported from epidemiological studies identified through a systematic search.

METHODOLOGY AND PRINCIPAL FINDINGS

The systematic search was conducted mainly in electronic databases but a few additional records were obtained from other sources. Retrieved entries were examined in order to identify available peer-reviewed epidemiological studies that found significant risk factors for infection using associative statistical methods. One hundred studies met the eligibility criteria and were suitable for data extraction. Epidemiological factors associated with increased risk of E. granulosus infection in dogs included feeding with raw viscera, possibility of scavenging dead animals, lack of anthelmintic treatment and owners' poor health education and indicators of poverty. Key factors associated with E. granulosus infection in intermediate hosts were related to the hosts' age and the intensity of environmental contamination with parasite eggs. E. multilocularis transmission dynamics in animal hosts depended on the interaction of several ecological factors, such as hosts' population densities, host-prey interactions, landscape characteristics, climate conditions and human-related activities.

CONCLUSIONS/SIGNIFICANCE

Results derived from epidemiological studies provide a better understanding of the behavioural, biological and ecological factors involved in the transmission of this parasite and hence can aid in the design of more effective control strategies.

Worldwide epidemiology of liver hydatidosis including the Mediterranean area

The worldwide incidence and prevalence of cystic echinococcosis have fallen dramatically over the past several decades. Nonetheless, infection with Echinococcus granulosus (E. granulosus) remains a major public health issue in several countries and regions, even in places where it was previously at low levels, as a result of a reduction of control programmes due to economic problems and lack of resources. Geographic distribution differs by country and region depending on the presence in that country of large numbers of nomadic or semi-nomadic sheep and goat flocks that represent the intermediate host of the parasite, and their close contact with the final host, the dog, which mostly provides the transmission of infection to humans. The greatest prevalence of cystic echinococcosis in human and animal hosts is found in countries of the temperate zones, including several parts of Eurasia (the Mediterranean regions, southern and central parts of Russia, central Asia, China), Australia, some parts of America (especially South America) and north and east Africa. Echinococcosis is currently considered an endemic zoonotic disease in the Mediterranean region. The most frequent strain associated with human cystic echinococcosis appears to be the common sheep strain (G1). This strain appears to be widely distributed in all continents. The purpose of this review is to examine the distribution of E. granulosus and the epidemiology of a re-emerging disease such as cystic echinococcosis.

Echinococcosis/hydatidosis: a severe threat in Mediterranean countries

Echinococcosis/hydatidosis is one of the most important parasitic zoonotic diseases in the world. Both cystic hydatidosis (CE) caused by Echinococcus granulosus and alveolar echinococcosis (AE) caused by E. multilocularis have been reported in several countries of the Mediterranean region (MR). E. granulosus has always been present in the MR and is the most common species. This parasite depends on the dog-sheep cycle and is actively transmitted in all pastoral regions where sheep, cattle and camelids predominate. E. multilocularis occurs only sporadically in limited areas of France, Serbia and Montenegro, Turkey, Tunisia and Morocco. However recent evidence indicates that it is spreading into other regions of the Mediterranean. Due to the lack of well-documented data, and to the fact that CE is not a notifiable disease in the majority of M countries, the precise incidence and prevalence of CE in humans and animals are not known. Published data suggests that prevalence is rather high in North Africa, Turkey, Greece, and in several regions of Italy and Spain. CE is an increasing public health and socio-economic concern due to the considerable morbidity rates that give rise to high economic losses both in the public health sector and in the livestock industry. Hospitalisation for human CE lasts from 2 weeks to more than 1 month in case of surgery. A number of factors contribute to the increase of prevalence and to the spreading of CE in the MR. These include the diversity of livestock production systems (predominantly extensive, traditional animal husbandry), small, ill-equipped and unsupervised slaughter-houses, illegal and family slaughtering, low public awareness of hydatid diseases, and the high population of stray dogs. Cyprus is the only country where an eradication programme has been successfully implemented. There have been, however, important developments in the last decade in CE epidemiology, in the diagnosis of canine infection, in strain characterisation and in immune strategies against CE in animals. This scientific progress, together with effective health education programmes, will likely improve control programmes and reduce the time required to achieve significant decreases in prevalence or eradication.

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

A 10-year (1998–2008) retrospective study was carried out to investigate the prevalence and long-term trend of hydatid disease in slaughtered herbivores in the large complex abattoir of Ahwaz (the capital of Khuzestan province, south-western Iran). A total of 3,583,417 animals including 2,815,982 sheep, 427,790 goats and 339,645 cattle were inspected macroscopically for hydatid cysts in the 10-year period, and overall 155,555 (4.24%) livers and 228,172 (6.37%) lungs were condemned. Cystic echinococcosis (CE) was responsible for 36.08% and 48.04% of total liver and lung condemnations, respectively. The prevalence of pulmonary hydatid disease in sheep, goats and cattle was 2.22, 5.43 and 6.99%, respectively; on the other hand, the prevalence of hepatic hydatid disease for those animals was 1.26, 2.57 and 2.80%, respectively. Data showed an overall downward long-term trend for CE in all livestock slaughtered during the study period (P < 0.01). Lung condemnation due to CE was significantly more common than liver condemnation for each animal separately (P < 0.001). The prevalence of liver and lung hydatidosis in sheep was significantly lower than that in other livestock (P < 0.001). The prevalence of hydatid disease recovered from the sheep, cattle and goats varied in different seasons, but there was no statistical difference between various seasons. The odds ratio of lung and liver condemnations due to hydatidosis showed a slightly different pattern in some years; however, the overall declining trend was still observed. The total annual economic loss incurred due to hydatidosis in all ruminants slaughtered at Ahwaz municipal abattoir was estimated to be US$459,659.6, based on the market prices in the year 2008. This number corresponds to a loss of US$300,620.4 for cattle, US$123,490.0 for sheep and US$35,549.2 for goats. The current results provide baseline data for the future monitoring of this potentially important disease in the region, and also suggest that a thorough investigation leading to a disease control strategy is required to reduce the economic and public health consequences of CE.

Molecular genetic characterization of different isolates of Echinococcus granulosus in east and southeast regions of Turkey

We used PCR-RFLP analysis of ribosomal ITS1 fragment using four different restriction enzymes and DNA sequencing of mitochondrial CO1 gene to investigate the genetic characteristics of isolates of Echinococcus granulosus obtained from different hosts (179 sheep, 19 cattle, 7 goat, 1 camel, 1 dog and 1 human) and regions (Elazig, Malatya, Erzurum, Van, Diyarbakir and Sanliurfa) of Turkey. The report represents the most comprehensive genotypic investigation of E. granulosus isolates undertaken in Turkey, with Turkish samples of cattle, goat, camel and dog origin being characterized for the first time. We show that the predominant genotype involved in E. granulosus transmission in Turkey is the common sheep strain (G1 genotype) infecting humans, cattle, sheep, goats, camels as well as the dog definitive host. Nevertheless, we urge that coordinators of local control programs in Turkey should take into consideration the potential occurrence and risk of additional strains of E. granulosus infecting humans and animal hosts, and plan accordingly.

Infectivity of Echinococcus granulosus protoscolices under different conditions of temperature and humidity

The aim of this study was to examine the effect of different temperatures and humidities on the infectivity of Echinococcus granulosus protoscolices. Eighteen dogs (6 groups, n = 3 each) were fed with offal mince harbouring approximately 20,000 protoscolices of E. granulosus of different viabilities. Dogs were infected with E. granulosus protoscolices of: (1) 5% viability at -10 degrees C and 50% relative humidity (RH); (2) 30% viability at 0 degrees C and 60% RH; (3) 20% viability at +10 degrees C and 65% RH; (4) 15% viability at +30 degrees C and 75% RH; (5) 11% viability at +40 degrees C and 80% RH; (6) 68% viability (control group). Dogs in each group were necropsied at 29-49 days post-infection. Mean intensities of E. granulosus recovered from dogs were 256.7 +/- 60.3 in the second group; 32.7 +/- 7.1 in the third group; 40.3 +/- 15.5 in the fourth group and 1533 +/- 513 in the control group. However, no parasites were recovered from the first and fifth groups. Results obtained in the present study show that larval stages could be infective for 1 to 4 weeks during spring, autumn or winter months when maximal temperatures are approximately 0-10 degrees C. In conclusion, cold-storage depots in slaughterhouses and abattoirs where sheep carcasses might be discarded should be kept at -20 degrees C for 2-3 days, dogs should be properly controlled and adequate control programmes must be established in areas where the disease is endemic.

The prevalence, intensity and viability of hydatid cysts in slaughtered animals in the Ardabil province of Northwest Iran

In a cross-sectional study, a total of 5381 slaughtered animals, namely 928 cattle, 243 buffaloes, 3765 sheep and 445 goats were inspected macroscopically for hydatid cysts in northwest Iran, with prevalence values of 38.3%, 11.9%, 74.4% and 20%, respectively, being recorded. Prevalences were higher in females compared with males, but a significant difference (P < 0.001) was only found in sheep and cattle. Most cases which were condemned were seen in the lungs of sheep (13.4%) indicating that sheep are the most important intermediate hosts for Echinococcus granulosus in this area.

Cystic Hydatic Disease in Sheep: Treatment with Percutaneous Aspiration and Injection with Dipeptide Methyl Ester

An in vitro and in vivo study was conducted to show the effect of dipeptide methyl ester on the protoscolices of Echinococcus granulosus and in naturally infected sheep. Easily punctured cysts were located by ultrasonography. A PAIR and PAI method were performed by the injection of dipeptide methyl ester into these cysts at a final concentration of 110 mmol/L. Follow-up was conducted monthly by ultrasonography. After injection of the compound, the sheep were sacrificed at different times from 6 to 17 weeks. The size and the morphological aspect of treated cysts were noted. Samples were collected for histology and electron microscopy. In conclusion, these studies revealed significant and rapid detachment of the membrane of the treated cyst and alteration of the inner membrane in less than 5 min after injection of the drug, confirming the effect of the compound on the laminated layer of the parasite.