Prevalence of Echinococcus granulosus infection in stray dogs and herbivores in Shiraz, Iran

First report of Crenosoma vulpis in Africa and Eucoleus aerophilus in Algeria

Introduction

Crenosoma vulpis and Eucoleus aerophilus are widely distributed lungworms infecting carnivores, mainly red foxes, and are localized in the trachea, bronchi and bronchioles. There are no reports from Africa regarding the presence of C. vulpis. The aim of the present study was to report a co-infection with C. vulpis and E. aerophilus in a red fox from Algeria.

Materials and methods

In January 2022, a road-killed male juvenile red fox (Vulpes vulpes) was collected from Bouhadjar-Tarf locality and was submitted for a complete parasitological necropsy. Detected nematodes were collected and preserved in ethanol for morphological and molecular identification. Tissue samples were also collected and analyzed by histopathological methods.

Results

Collected nematodes were identified as a male C. vulpis and several Eucoleus aerophilus. The histological techniques of the lung tissue did not reveal the presence of any larvae, or lung inflammation.

Conclusion

To the best of our knowledge, this is the first report of C. vulpis infecting a carnivore in this continent, highlighting the importance of further studies to update the geographical distribution of C. vulpis. E. aerophilus was first reported in Algeria. Red foxes are important spreaders of parasitic diseases. Further studies are required for a better understanding of its epidemiology across North Africa and other areas overlapping the range of the red fox.

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.

Africa-wide meta-analysis on the prevalence and distribution of human cystic echinococcosis and canine Echinococcus granulosus infections

BACKGROUND

Echinococcosis is a neglected zoonosis of increasing public health concern worldwide. According to the World Health Organization, 19,300 lives and 871,000 disability-adjusted life-years are lost globally each year because of cystic echinococcosis. Annual costs associated with cystic echinococcosis were estimated at US$ 3 billion because of treatment of cases and losses in the livestock industry.

METHODS

We performed the random-effects model of meta-analysis using 51-year (1970-2021) data available from AJOL, Google Scholar, PubMed, Science Direct, Scopus and Web of Science. We also applied the Joanna Briggs Institute critical appraisal instrument for studies reporting prevalence data, the Cochran's Q-test, Egger's regression test and the single study deletion technique to respectively examine within-study bias, heterogeneity, across-study bias and sensitivity.

RESULTS

Thirty-nine eligible studies on human cystic echinococcosis (HCE) from 13 countries across the five African sub-regions showed an overall prevalence of 1.7% (95% CI 1.1, 2.6) with a statistically significant (P < 0.001) sub-group range of 0.0% (95% CI 0.0, 14.1) to 11.0% (95% CI 7.6, 15.7). Highest prevalences were observed in Eastern Africa (2.7%; 95% CI 1.4, 5.4) by sub-region and Sudan (49.6%; 95% 41.2, 58.1) by country. Another set of 42 studies on Echinococcus granulosus infections (EGI) in dogs from 14 countries across the five African sub-regions revealed an overall prevalence of 16.9% (95% CI 12.7, 22.3) with a significant (P < 0.001) variation of 0.4 (95% CI 0.0, 5.9) to 35.8% (95% CI 25.4, 47.8) across sub-groups. Highest prevalences of E. granulosus were observed in North Africa (25.6%; 95% CI 20.4, 31.6) by sub-region and Libya (9.2%; 95% CI 5.7, 13.9) by country.

CONCLUSION

Human cystic echinococcosis and EGI are respectively prevalent among Africans and African dogs. We recommend a holistic control approach that targets humans, livestock, dogs and the environment, which all play roles in disease transmission. This approach should involve strategic use of anthelminthics in animals, standardized veterinary meat inspection in abattoirs, control of stray dogs to reduce environmental contamination and proper environmental sanitation. Mass screening of humans in hyper-endemic regions will also encourage early detection and treatment.

Serosurvey of Cystic Echinococcosis and Related Risk Factors for Infection in Fars Province, Southern Iran: A Population-Based Study

Cystic echinococcosis (CE) is a common zoonotic infection in all provinces of Iran, especially in areas where people live on agriculture and animal husbandry. The current cross-sectional population-based study is aimed at determining the seroprevalence of CE in Kavar County, Fars province, southern Iran. Blood samples were collected from 1500 individuals (749 males and 751 females). Anti-hydatid cyst antibodies were detected, using a recombinant B8/1 antigen of Echinococcus graunlosus in an ELISA system. Multivariate logistic regression analysis was used to find out the independent risk factor for CE seropositivity. Anti-hydatid cyst antibodies were detected in the sera of 131 out of 1500 participants, corresponding to a seroprevalence rate of 8.73%. With a statistically significant difference ( $p<0.05$ ), the seroprevalence of hydatid cyst in males and females was 5% and 7%, respectively. Differences in the seropositivity of hydatid cysts were also statistically significant by occupation ( $p<0.05$ ). The seroprevalence of hydatid cyst was significantly higher in the age group of 35-45 years than in other age groups ( $p<0.05$ ). Multivariate logistic regression showed that only age was associated with seropositivity to CE ( $\text{OR}=2.23$ , 95% CI: 1.33-3.72). Moreover, there was a statistically significant association between seropositivity to hydatid cysts and underlying diseases such as hypertension ( $p=0.049$ ) and fatty liver ( $p=0.048$ ). The findings of this study indicate that the seroprevalence rate of CE is relatively high in the Fars province, southern Iran, and this high rate of infection is mainly linked to people’s jobs and lifestyles.

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.

Cystic Echinococcosis: Knowledge, Attitude, and Practices (KAP) among Surgically Operated Cases in Fars Province, Southern Iran

Introduction

Cystic echinococcosis (CE) is a neglected zoonotic disease caused by Echinococcus granulosus with major health and economic burden. The information on how the community members perceive the disease is crucial in order to recommend an effective preventive and control plan. The current study is aimed at finding out knowledge, attitude, and practices (KAP) of surgically operated cases of hydatid cyst in educational hospitals of Shiraz in Fars Province, southern Iran, toward the CE.

Methods

A cross-sectional survey was conducted among 180 CE patients who underwent surgery due to CE. Using a well-designed questionnaire, a telephone-based survey was carried out to collect the data. The contents of the questionnaire included basic personal information and questions related to the participants' knowledge, attitude, and behavioral patterns toward CE. Univariate and then multivariate linear regression analyses were used to identify factors associated with the KAP. Unstandardized regression coefficients (β) and odds ratios (ORs) and their 95% confidence intervals (CIs) were used to quantify the associations between variables and KAP.

Results

A total of 180 CE patients with a mean age of 35.64 (±17.59) years were recruited. The mean score of participant's knowledge was 8.7 (SD = 2.8, range: 0-17), whereas these scores were 1.3 (SD = 0.7, range 0-2) for attitude and 1.2 (SD = 1.0, range 0-4) for practice. Findings of the study demonstrated that 20 of the participants (11.1%) had good knowledge towards CE, 82 (45.6%) demonstrated a positive attitude, and 57 (47.5%) without having dogs demonstrated a good practice towards CE (score = 2/2), while from 60 dog owners, only 7 (11.6%) participants demonstrated good practice (score 3 and 4/4). Factors that were associated with knowledge were age (OR = −0.49, P value = 0.001) and educational level (OR = 0.668, P value = 0.001), where higher age was associated with lower knowledge and also higher educational levels were associated with higher knowledge regarding hydatid cyst. Regarding attitude, only living location had a significant association with participants' attitude where those who were living in urban areas demonstrating a more positive attitude towards CE (OR = 0.261, P value = 0.022). The practice of the participants was grouped into dog owners and participants with no dogs, in which among participants who did not own a dog, those living in urban areas demonstrating weaker practice towards CE (OR = −0.491, P value>0.001). Moreover, a lack of counseling of patients after the surgery on how to prevent reinfection was noticed.

Conclusion

Findings of the study revealed that the CE patients in southern Iran had poor knowledge and attitude toward the disease, and their practice may help in maintaining the disease in the community. Health education is highly needed to increase community awareness and to prevent and control this neglected parasitic infection in the area.

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

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

Environmental, climatic and host population risk factors of human cystic echinococcosis in southwest of Iran

BACKGROUND

Cystic echinococcosis (CE), a worldwide zoonotic disease, is affected by various biological and environmental factors. We investigated dog/livestock populations, climatic and environmental factors influencing the distribution of human CE cases in Fars province, southwest Iran.

METHODS

We mapped the addresses of 266 hospitalised CE patients (2004-2014) and studied the effects of different temperature models, mean annual rainfall and humidity, number of frosty days, slope, latitude, land covers, close proximity to nomads travel routes, livestock and dog densities on the occurrence of CE using geographical information systems approach. Data were analyzed by logistic regression.

RESULTS

In the multivariate model predicting CE, living in an urban setting and densities of cattle and dogs were the most important CE predictors, sequentially. Dry (rained) farm, density of camel and sheep, close proximity to nomads travel routes, humidity, and slope also were considered as the determinants of CE distribution, when analyzed independently. Slope had a negative correlation with CE while temperature, frost days and latitude were not associated with CE.

CONCLUSIONS

In our study, an urban setting was the most important risk factor and likely due to a combination of the high density of key life cycle hosts, dogs and livestock, a large human susceptible population and the high number of abattoirs. Farmland and humidity were highly suggestive risk factors and these conditions support the increased survival of Echinococcus granulosus eggs in the soil. These findings support the development of strategies for control of disease. More research is needed test optimal interventions.

Epidemiological and molecular studies on Echinococcus granulosus from free-roaming dogs in Southeast Iran

Background and Aim:

Cystic echinococcosis (CE), as a major zoonotic helminth infection, imposes remarkable socioeconomic burden on many endemic countries across the world, including Iran. Due to the high importance of free-roaming dogs in the transmission of CE, epidemiological and molecular studies in this type of hosts are required in the endemic regions. This study aimed to investigate the epidemiology and genotyping of Echinococcusgranulosus isolated from stray dogs in Kerman, Southeast Iran.

Materials and Methods:

Eighty-four samples were isolated from stray dogs in the city and suburbs of Kerman in coordination with the health authorities and the municipality office for rabies control and dog population management. Dog demographic data, including age and sex were collected. The worm was isolated by necropsy and genomic DNA was extracted and partial cytochrome c oxidase subunit 1 gene was amplified using specific primers. Phylogenetic and Templeton-Crandall-Sing (TCS) network analyses were carried out on the sequence data.

Results:

The overall prevalence of CE in the surveyed dogs was 10.7% (9/84 cases). Out of 84 stray dogs, 33 (39.3%) and 51 (60.7%) cases were male and female, respectively. There was not a statistically significant difference between the infection and gender of dogs. However, infection is shown more in dogs under one year of age with a statistically significant difference (p<0.05). The results of molecular studies indicated E. granulosus G1 genotype for all isolates. The high presence of free-roaming dogs in urban and peri-urban areas and high frequency of parasite in this animal is a risk factor for humans in the region. Haplotype sequence analysis on the dog isolates revealed a close relationship with other E. granulosus isolates in Kerman.

Conclusion:

The findings of this study provide evidence-based data about the epidemiological and molecular characteristics of CE in dog definitive hosts of Southeast Iran. Further studies are required to understand the prevalence and parasite genotypes in dogs in Iran.

Prevalence of Echinococcus granulosus taeniasis in stray dogs in the region of Constantine (North-East Algeria)

In North Africa, the domestic dog is regarded as the main reservoir for infection by Echinococcus granulosus of domestic livestock and man. In Algeria, there is very little data on the rate of infestation of dogs, while the prevalence of E. granulosus in the definitive host is a very reliable marker of the potential risk of transmission of cystic tapeworm to humans and livestock. To find out this information, a survey was conducted to assess the prevalence of infection with E. granulosus in stray dogs in the region of Constantine (North-East Algeria). We autopsied and examined 120 stray dogs, 22 (18.3%) of which were infected with E. granulosus, with an average intensity of infestation of 249 worms. The prevalence in the area of survey was evaluated: 15.5% (14/90) and 26.6% (8/30) dogs were parasitized by E. granulosus in urban and rural areas respectively. The influence of age on the rate of infection was very marked. In addition, the appreciation of the prevalence of parasitism by cestodes as a whole showed that 56 (46.6%) animals out of 120 were infected. Facing such a situation of endemic tapeworm parasitism, with a potential risk of transmission to humans, there is an urgent need to take measures to control and break the epidemiological cycles of the parasite.

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.

Echinococcus granulosus in humans associated with disease incidence in domestic animals in Kermanshah, west of Iran

Hydatidosis is one of the important zoonotic diseases that cause considerable economic losses and public health problems worldwide. This study was conducted to determine the prevalence Echinococcus granulosus in people and slaughtered animals in Kermanshah province, west of Iran. Hospitals data and meat-inspection records in Kermanshah abattoir were used in this study. A total number of 32,130 slaughtered livestock (7000 cattle, 19,950 sheep and 5180 goats) was inspected in the 3-year period and overall 2043 (6.35 %) were infected. The highest and lowest prevalence was recorded in cattle and goats, respectively. In human, Cystic echinococcosis affected more females (54 %) than males (46 %) with a 1.17 male to female ratio. Rate of disease in urban and rural regions were 46 and 54 %, respectively. The youngest and the oldest patient operated were 7 and 87 years old, respectively, and the age group 21-40 years (41.2 %) were the most affected. A significantly higher number of hydatid cysts were recorded in the liver than in other sites. The ratio of hepatic hydatidosis to pulmonary hydatidosis was 2.46. The results showed that hydatidosis is of great importance in this area and serious attention is needed to prevent and control the disease.

Application of multiplex PCR for the simultaneous detection of Taenia spp. from domestic dogs in the north of Iran

The family Taeniidae is of great importance in the medical and veterinary fields, particularly in the tropics and subtropics. Identification of eggs of different Taenia spp. in the final host by morphological examination is difficult owing to their similarity. Therefore, a multiplex polymerase chain reaction (PCR) targeting a mitochondrial gene was applied to identify morphologically indistinguishable eggs. Fecal samples from 100 domestic dogs, from the Mazandaran province in Iran, were examined using the flotation/sieving method followed by multiplex PCR. Taeniid eggs were observed in 24 % samples, of which 12 %, 10 %, and 2 % were infected with Echinococcus granulosus, Taenia spp., and both E. granulosus and Taenia spp., respectively. E. multilocularis was absent in these samples. The prevalence of E. granulosus in the examined domestic dogs as definitive hosts in north of Iran was high (14 %). Therefore, people living in this region of Iran are in danger of acquiring hydatid cyst, which is a serious public health problem.

[Raw-meat-based diets (RMBD) as a feeding principle for dogs]

BARF (Bone And Raw Food) is an increasing trend for feeding dogs in Germany. This article provides an overview of the history and principles of this type of feeding. Risks of feeding raw-meat diets include infections of dogs with parasites, bacteria and viruses. Some of these pathogenic organisms also have zoonotic potential. Additionally, raw-meat diets often show nutritional imbalances. Over-supplementation and deficiencies of nutrients are frequently found, especially regarding calcium, the trace elements copper, zinc and iodine, vitamins A and D and the calcium   :   phosphorus ratio. This malnutrition can cause clinical symptoms. Therefore, checking and optimising the diet by a specialized veterinarian is strongly recommended.

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.

Genetic characterization of Echinococcus granulosus from a large number of formalin-fixed, paraffin-embedded tissue samples of human isolates in Iran

Cystic echinococcosis (CE), caused by the larval stage of Echinococcus granulosus, presents an important medical and veterinary problem globally, including that in Iran. Different genotypes of E. granulosus have been reported from human isolates worldwide. This study identifies the genotype of the parasite responsible for human hydatidosis in three provinces of Iran using formalin-fixed paraffin-embedded tissue samples. In this study, 200 formalin-fixed paraffin-embedded tissue samples from human CE cases were collected from Alborz, Tehran, and Kerman provinces. Polymerase chain reaction amplification and sequencing of the partial mitochondrial cytochrome c oxidase subunit 1 gene were performed for genetic characterization of the samples. Phylogenetic analysis of the isolates from this study and reference sequences of different genotypes was done using a maximum likelihood method. In total, 54.4%, 0.8%, 1%, and 40.8% of the samples were identified as the G1, G2, G3, and G6 genotypes, respectively. The findings of the current study confirm the G1 genotype (sheep strain) to be the most prevalent genotype involved in human CE cases in Iran and indicates the high prevalence of the G6 genotype with a high infectivity for humans. Furthermore, this study illustrates the first documented human CE case in Iran infected with the G2 genotype.

Using morphometry of the larval rostellar hooks to distinguish Iranian strains ofEchinococcus granulosus

Human cystic echinococcosis is widely distributed throughout Iran, where sheep, cattle, goats, camels and other animals act as intermediate hosts. It appears that morphometry of the rostellar hooks on the protoscoleces of the causative parasite, Echinococcus granulosus, can be used to separate the strains or variants of the parasite to be found in humans and livestock in Iran. Multivariate statistical procedures, including principal-component analysis and discriminant-function analysis (DFA), were used to explore the morphometric data obtained from the larval hooks of Iranian samples of E. granulosus. Although five physical variables were initially considered, the results of the PCA indicated that just two factors (based on the length of hooks and number of hooks) accounted for 91.6% of the variance observed in the hook measurements. The results of the DFA allowed the correct classification of all the samples. The presence in Iran of the sheep and camel strains of the parasite was confirmed. The sheep strain was the most common variant encountered, being recovered from sheep, cattle, goats, humans and occasionally camels. Most of the metacestode samples from camels and a few of those from cattle (five of 30), sheep (one of 27) and humans (two of 23) were found to be of the camel strain. These results indicate that larval-hook morphology is a valid method for identifying E. granulosus strains in Iran, and one that is potentially useful for epidemiological studies.

An epidemiological survey on intestinal helminths of stray dogs in Mashhad, North-east of Iran

This research was conducted to determine the prevalence of gastrointestinal helminths in stray dogs in the northeast of Iran, with special attention to those parasites that can be transmitted to human. In this experiment, a total of 72 adult and 18 juvenile stray dogs were collected and necropsied for the presence of helminth parasites from October 2011 to August 2012. The overall prevalence of gastrointestinal helminths was 86 % (95 % CI: 79.2-92.8 %). The observed helminths of the gastrointestinal tract were listed as follows: Toxocara canis (29 %), Toxascaris leonina (7 %), Ancylostoma caninum (2 %), Taenia hydatigena (43 %), Dipylidium caninum (39 %), Echinococcus granulosus (38 %), Mesocestoides lineatus (16 %), Taenia multiceps (11 %), Taenia ovis (3 %). There were no significant differences for the prevalence of gastrointestinal helminths between female (83.6 %) and male (89.7 %) and between young (89 %) and adult (72.2 %) animals. However, the prevalence of E. granulosus, T. hydatigena and D. caninum showed an increasing trend with increasing host age, significantly. Based on our data, it is important to point out the presence of zoonotic agents, namely E. granulosus and T. canis in stray dogs in the investigated area. Due to its impact on public health, appropriate control measures should be taken and it is recommended to determine the most appropriate preventive methods.

Immunoproteomics approach for EPC1 antigenic epitope prediction of G1 and G6 strains of Echinococcus granulosus

It is important to establish the diagnosis of cystic echinococcosis (CE) infection and begin control management. Currently, it is difficult to make an accurate diagnosis of CE without the availability of an accurate test, which requires the use of sensitive and specific antigens. Using recombinant antigens the sensitivity and specificity of the CE serology assays could be improved considerably. Recently, a highly antigenic protein named EPC1was characterized and isolated from an Echinococcus granulosus protoscoleces. The current study was designed to assess the sequences of EPC1 isolated from different intermediate hosts of E. granulosus. In addition, identification of a highly antigenic linear B cell epitope was found within EPC1 antigen candidate. The EPC1 sequence contains coding and non-coding regions and was compared between two predominant strains (G1 and G6) in Iran. Sequence polymorphism was not found in protein coding regions, suggesting that these regions may be useful for identification of protein expression as an antigen. The average antigenic activity for the whole protein is above 1.1, and hydrophobicity below 0 indicates that it is hydrophilic. Structural analysis showed alpha helical regions in amino acids 6-25, 35-44, 52-62, and 72-78. Nine B cell epitope residues were identified out of 67 total residues. The identity of EPC1 sequence in both G1 and G6 genotypes affects the antigenic efficacy of EPC1and suggests the recombinant protein will be useful in serological assays in the regions where the two strains are prevalent.

Comparison of the usefulness of hydatid cyst fluid, native antigen B and recombinant antigen B8/1 for serological diagnosis of cystic echinococcosis

For serodiagnosis of cystic echinococcosis (CE), the usefulness of three native antigens, a hydatid cyst fluid (HCF) obtained from infected sheep in China, two types of antigen B prepared from each HCF obtained in Iran and China, and one recombinant antigen B8/1 (RAgB), were evaluated by ELISA using a total of 155 serum samples from Iran, Turkey, China and Japan. Both the Iranian native antigen B and RAgB had high sensitivity, but RAgB showed an excellent specificity in comparison with native antigens because none of the serum samples of healthy people from Iran and Japan became positive with this antigen except one case of taeniasis. The taeniasis case exceptionally showing cross reactivity with all antigens was considered to be co-infected with Echinococcus granulosus and Taenia saginata. The recombinant antigen showing a high diagnostic odds ratio in comparison with other evaluated antigens might be recommended for diagnosis of CE in different CE-endemic areas.

Giant primary adrenal hydatid cyst presenting with arterial hypertension: a case report and review of the literature

Introduction

A primary hydatid cyst of the adrenal gland is still an exceptional localization. The adrenal gland is an uncommon site even in Morocco, where echinococcal disease is endemic.

Case presentation

We report the case of a 64-year-old Moroccan man who presented with the unusual symptom of arterial hypertension associated with left flank pain. Computed tomography showed a cystic mass of his left adrenal gland with daughter cysts filing the lesion (Type III). Despite his negative serology tests, the diagnosis of a hydatid cyst was confirmed on surgical examination. Our patient underwent surgical excision of his left adrenal gland with normalization of blood pressure. No recurrence has occurred after 36 months of follow-up.

Conclusion

There are two remarkable characteristics of this case report; the first is the unusual location of the cyst, the second is the association of an adrenal hydatid cyst with arterial hypertension, which has rarely been reported in the literature.

Seroepidemiological survey of helminthic parasites of stray dogs in Sari City, northern Iran

The objective of this study was to determine the prevalence rate of helminthic parasites in stray dogs' population especially zoonotic infections and to identify potential risk factors in the different areas of Sari city in Caspian area, north of Iran. During the period from April to September 2007, 50 stray dogs were collected from urban areas of Sari city. Recovered parasites were fixed in alcohol and stained by carmine then observed by microscope. The taxonomic study was carried out by measuring different parts of the body of helminthes and statistical tests were performed using the Chi-square test. A total of 27 adult and 23 juvenile stray dogs were collected and the overall prevalence rate of infection was 90%. The three most common helminthes were Toxocara canis (60%), Ancylostoma caninum (46%) and Dipylidium caninum (36%). Other parasites were Uncinaria stenocephala (12%), Taenia hydatigena (6%), Spirocerca lupi (6%), Dirofilaria immitis (6%), Toxascaris leonina (2%), Rictularia sp. (2%), Taenia ovis (2%) and Taenia taeniformis (2%). Five species of zoonotic helminthes recovered were T. canis, A. caninum, U. stenocephala, D. caninum and D. immitis. Hookworm infections (58%) were more common significantly in the young stray dogs (p < 0.01). In regard to prevalence ofA. caninum, T. canis and U. stenocephala, there was significant difference between juvenile and adult dogs (p < 0.05). The results highlight the potential role of stray dogs for transmission of helminthic parasites particularly zoonotic parasites that are a significant risk to human health.

The prevalence and fertility of hydatid cysts in buffaloes from Iran

Cystic echinococcosis caused by Echinococcus granulosus is considered to be an important parasitic infection in livestock. In the present study, which aimed to determine the epidemiology of hydatidosis in buffalo in Iran, slaughterhouses of West Azerbaijan (Urmia), East Azerbaijan (Tabriz), Ardabil (Ardabil), Gilan (Rasht and Hashtpar) and Khuzestan (Ahvaz) were inspected. Age, sex and infected organs were recorded separately, and the observed cysts were examined for fertility and viability. Our results showed that 344 (9%) of 3832 inspected buffaloes were infected with hydatid cysts. The maximum and minimum infection rates occurred in Khuzestan (9.9%) and Ardabil (8%) provinces, respectively. There was no significant difference in the rate of infection in all provinces. Of 344 infected buffaloes, the rate of fertility was 7.3% and the rate of viability in fertile cysts was 78.75%. Hydatid cysts were more prevalent in female compared with male buffaloes (P < 0.05). There was a positive correlation between the age and number of infected hosts in all provinces except East Azerbaijan. The prevalence of infection in lungs was significantly higher than that in the livers of buffaloes in the provinces studied (P < 0.001). In conclusion, the fertility of hydatid cysts in buffaloes was low, as previously demonstrated in cattle, and this animal may play a minor role in the epidemiology of hydatidosis in Iran.

Primary hydatid cyst of the adrenal gland: a case report and review of the literature

Hydatid cyst of adrenal gland is rare and usually incidentally found as a part of disseminated disease. Herein we report a rare case of primary adrenal hydatid cyst who presented with unusual symptom of arterial hypertension from an endemic country.

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.

Evaluation of different chemical agents on the germinative layer of sheep hydatid cyst after implantation to peritoneal cavity of BALB/c

In spite of the use of protoscolocidal agents during hydatid cyst surgery, a notable rate of disease recurrence in postoperation patients is still observed. The question remains whether living protoscolices lead to recurrence or the recurrence is due to the remainder of the germinative layer in the peritoneal cavity. The aim of this study was in vivo evaluation of different chemical (protoscolicidal) solutions on the germinative layer of the hydatid cyst. The germinative layer of sheep hydatid cyst was separated under sterile condition, divided into 0.25-cm(2) parts, and exposed to 0.5% cetrimide, 0.5% silver nitrate, 20% hypertonic saline, 15% dextrose and 25% dextrose, and normal saline as negative control for 2 min. The exposed germinative layers were implanted into the peritoneal cavity of 90 Balb/C mice (15 mice in each group). After nine months, the peritoneum was evaluated macroscopically as well as microscopically for the presence of any hydatid cyst. No hydatid cyst was observed in the peritoneal cavity of the exposed mice. The role of the germinative layer for inducing hydatid cysts in mice is questionable. However, the present study showed that the germinative layer had no role in the induction of hydatid cyst in these laboratory animals.

Human cystic echinococcosis in Yasuj District in Southwest of Iran: an epidemiological study of seroprevalence and surgical cases over a ten-year period

Cystic echinococcosis is a zoonotic infection of humans and domestic animals caused by the larval stages of the cestode Echinococcus granulosus. Cystic echinococcosis is one of the most important zoonotic diseases in Iran, where human cases are frequently reported from different regions of the country. The objective of this study was to determine the sero-epidemiological and surgical cases of human hydatidosis in the Yasuj district, a region in southwest of Iran. Serum samples were taken from 500 individuals attending Yasuj health centers. Anti-hydatid cyst antibody was checked by enzyme-linked immunosorbent assay (ELISA), using antigen B. Moreover, retrospective studies were carried out using local hospital records of CE patients between 1997 and 2006. Results of the sero-epidemiological study showed that 36 out of 500 cases (7.2%) have antibody against hydatid cyst. Of these 36 cases, 49.6% were women and 50.4% were men. The highest rate of infection was recorded in individuals aged between 30 and 39 years. Hospital records showed that during the 10 years, 105 cases of hydatidosis were admitted in Yasuj hospitals. Of all cases, 70 (66.7%) were women and 35 (33.3%) were men. Hepatic cyst was recorded in 81% of the cases where nephrotic cysts were the second most prevalent ones. Recurrence of the disease was noted in 14.3% of all cases. Results of this study demonstrated that hydatidosis is an important endemic disease, with a nearly constant prevalence rate during the last 10 years, in Yasuj district in Iran. Further studies are needed to investigate the reasons for high rate of surgical cases in housewives and striking prevalence of hydatidosis in a specific (30-40 years) age group.

Echinococcus granulosus strain differentiation in Iran based on sequence heterogeneity in the mitochondrial 12S rRNA gene

Parasite strain characterization is essential for the establishment of a prevention and control strategy in any endemic area. The aim of this study was to characterize different Echinococcus granulosus isolates from Iran by using DNA sequences of the mitochondrial 12S rRNA gene. Thirty livers and lungs of cattle, sheep and goats naturally infected with E. granulosus were collected from abattoirs in northern and western Iran between June and October 2007. These samples yielded 18 fertile cysts which we used for the genetic work. We designed and tested two new primer pairs which specifically amplify portions of the mitochondrial 12S rRNA gene of the two strains (G1 and G6) of E. granulosus known to occur in Iran. One primer pair amplified a fragment of 259 base pairs (bp) from only the G1 strain. The second pair amplified a fragment of 676 bp from the G6 strain. The G1 genotype was identified in all fertile cyst samples, in agreement with previous studies in Iran. Ten of our samples and a single reference sample of the G6 strain were sequenced and compared with the G1 and G6 sequences deposited in GenBank.

Hydatidosis in camels (Camelus dromedarius) and their potential role in the epidemiology of Echinococcus granulosus in Iran

Hydatid cysts were recovered from 35.2% (233/661) of camels (Camelus dromedarius) slaughtered in five different regions of Iran. The degree of prevalence between males (34.4%) and females (36.6%) was not statistically significant. The highest rate of infection (59.3%) was found in the Isfahan region (in the central part of Iran) while the lowest (25.7%) was found in Kerman province. The organ distribution of cysts was 49.4% in lungs alone, 30.0% in both liver and lungs, 14.6% in liver only and 6.0% in other organs. Therefore, the lungs were the predominant sites of the hydatid cyst. The range in the number of cysts was 1–48 in infected animals. The majority of the camels had 1–5 cysts, with 21.9%, 11.6% and 5.6% of infected camels having 6–10, 11–20 and 21 or more cysts respectively. There was a direct relationship between the rate and intensity of infection and host age. The fertility rate of lung cysts (69.7%) was higher than that of liver cysts (58.7%) and other organs (50.0%) whilst the viability rate of protoscoleces of liver fertile cysts (80.3%) was significantly higher than that of lung cysts (55.8%) and other organs (57.1%). The role of camels in the epidemiology of Echinococcus granulosus in Iran is discussed.

A study on intestinal helminthes of dogs, foxes and jackals in the western part of Iran

Human infection especially with helminth parasites is an emerging health issue, as the human environment is increasingly shared with infected animals, either pets or wild life. In this survey, the intestinal content of 83 stray dogs, 22 red foxes and 10 golden Jackals collected from the West Azarbaijan, Kordestan and Kermanshah provinces in the west of Iran, were studied for the presence of helminth parasites. The percentage of different species recovered from these animals is listed as follows: From stray dogs: Toxocara canis (6.02%), Toxascaris leonina (32.53%), Ancylostoma caninum (3.61%), Oxynema sp. (1.35%), Rictularia affinis (12.05%), Taenia hydatigena (53.01%), Taenia ovis (7.23%), Taenia multiceps (4.82%), Echinococcus granulosus (13.25%), Dipylidium caninum (38.55%), Mesocestoides lineatus (26.50%) and Macracanthorhynchus hirudinaceus (4.82%). From red foxes: T. canis (4.54%), T. leonina (31.82%), A. caninum (4.54%), Uncinaria stenocephala (13.64%), Oxynema sp. (9.09%), R. affinis (54.54%), Strongyloides sp. (4.54%), Physaloptera sp. (4.54%), T. hydatigena (9.09%), E. granulosus (4.54%), D. caninum (9.09%), M. lineatus (81.82%), Joyeuxiella pasqalei (27.27%), Diplopylidium nolleri (4.54%), M. hirudinaceus (22.72%) and Macracanthorhynchus sp. (9.09%). From golden jackals: T. canis (10%), T. leonina (30%), R. affinis (50%), T. hydatigena (10%), D. caninum (20%), M. lineatus (70%), J. pasqalei (30%.), Alaria canis (10%), M. hirudinaceus (30%) and Macracanthomynchus sp. (10%).

In vitro protoscolicidal effects of hypertonic glucose on protoscolices of hydatid cyst

To evaluate the protoscolicidal effects of various concentrations of hypertonic glucose, live protoscolices of sheep were exposed to 10%, 15%, 25% and 50% glucose solutions. Cetrimide (0.5%), silver nitrate (0.5%) and hypertonic saline (20%) were used as positive controls, while physiological saline was used as a negative control. After 1, 2 and 5 min, the protoscolicidal effects were determined by 1% eosin. A 25% glucose solution had no significant protoscolicidal effect. However, a 50% glucose solution revealed higher protoscolicidal effect than 0.5% silver nitrate but weaker effect than 0.5% cetrimide; the effect was comparable with that of 20% hypertonic saline. The results showed that hypertonic glucose solution is highly effective in killing protoscolices of Echinococcus granulosus in vitro.