[Construction and application of a risk index of Echinococcus infection based on the classification of echinococcosis lesions].

OBJECTIVE: To investigate the feasibility of constructing the risk index of Echinococcus infection based on the classification of echinococcosis lesions, so as to provide insights into the management of echinococcosis. METHODS: The imaging data of echinococcosis cases were collected from epidemiological surveys of echinococcosis in China from 2012 to 2016, and the detection of incident echinococcosis cases was captured from the annual echinococcosis prevention and control reports across provinces (autonomous regions) and Xinjiang Production and Construction Corps in China from 2017 to 2022. After echinococcosis lesions were classified, a risk index of Echinococcus infection was constructed based on the principle of discrete distribution marginal probability and multi-group classification data tests. The correlation between the risk index of Echinococcus infection and the detection of incident echinococcosis cases was evaluated in the provinces (autonomous regions and corps) from 2017 to 2022, and the correlations between the short and medium-term risk indices and between the medium and long-term risk indices of Echinococcus infection were examined using a univariate linear regression model. RESULTS: A total of 4 014 echinococcosis cases in China from 2012 to 2016 were included in this study. The short-, medium- and long-term risk indices of E. granulosus infection varied in echinococcosis-endemic provinces (autonomous regions and corps) of China (χ2 = 4.12 to 708.65, all P values < 0.05), with high short- (0.058), medium- (0.137) and long-term risk indices (0.104) in Tibet Autonomous Region, and the short-, medium- and long-term risk indices of E. multilocularis infection varied in echinococcosis-endemic provinces (autonomous regions and corps) of China (χ2 = 6.74 to 122.60, all P values < 0.05), with a high short-term risk index in Sichuan Province (0.016) and high medium- (0.009) and long-term risk indices in Qinghai Province (0.018). There were no significant correlations between the risk index of E. granulosus infection and the detection of incident cystic echinococcosis cases during the study period (t = -0.518 to 2.265, all P values > 0.05), and strong correlations were found between the risk indices of E. multilocularis infection and the detection of incident alveolar echinococcosis cases (including mixed type) in 2018, 2020, 2021, 2022, during the period from 2017 through 2020, from 2017 through 2021, from 2017 through 2022 (all r values > 0.7, t = 2.521 to 3.692, all P values < 0.05). Linear regression models were established between the risk index of E. multilocular infection and the detection of alveolar echinococcosis cases (including mixed type), and the models were all statistically significant (b = 0.214 to 2.168, t = 2.458 to 3.692, F = 6.044 to 13.629, all P values < 0.05). The regression coefficients for the correlations between the medium- and short-term, and between the long- and medium-term risk indices of E. granulosus infection were 2.339 and 0.765, and the regression coefficients for the correlations between the medium- and short-term, and between the long- and medium-term risk indices of E. multilocular infection were 0.280 and 1.842, with statistical significance seen in both the regression coefficients and regression models (t = 16.479 to 197.304, F = 271.570 to 38 928.860, all P values < 0.05). CONCLUSIONS: The risk index of Echinococcus infection has been successfully established based on the classification of echinococcosis lesions, which may provide insights into the prevention and control, prediction, diagnosis and treatment, and classified management of echinococcosis.

Prevalence and spatial distribution characteristics of human echinococcosis in China.

BACKGROUND: Echinococcosis is a zoonotic parasitic disease caused by larval stages of cestodes belonging to the genus Echinococcus. The infection affects people's health and safety as well as agropastoral sector. In China, human echinococcosis is a major public health burden, especially in western China. Echinococcosis affects people health as well as agricultural and pastoral economy. Therefore, it is important to understand the prevalence status and spatial distribution of human echinococcosis in order to advance our knowledge of basic information for prevention and control measures reinforcement. METHODS: Report data on echinococcosis were collected in 370 counties in China in 2018 and were used to assess prevalence and spatial distribution. SPSS 21.0 was used to obtain the prevalence rate for CE and AE. For statistical analyses and mapping, all data were processed using SPSS 21.0 and ArcGIS 10.4, respectively. Chi-square test and Exact probability method were used to assess spatial autocorrelation and spatial clustering. RESULTS: A total of 47,278 cases of echinococcosis were recorded in 2018 in 370 endemic counties in China. The prevalence rate of human echinococcosis was 10.57 per 10,000. Analysis of the disease prevalence showed obvious spatial positive autocorrelation in globle spatial autocorrelation with two aggregation modes in local spatial autocorrelation, namely high-high and low-high aggregation areas. The high-high gathering areas were mainly concentrated in northern Tibet, western Qinghai, and Ganzi in the Tibetan Autonomous Region and in Sichuan. The low-high clusters were concentrated in Gamba, Kangma and Yadong counties of Tibet. In addition, spatial scanning analysis revealed two spatial clusters. One type of spatial clusters included 71 counties in Tibet Autonomous Region, 22 counties in Qinghai, 11 counties in Sichuan, three counties in Xinjiang Uygur Autonomous Region, two counties in Yunnan, and one county in Gansu. In the second category, six types of spatial clusters were observed in the counties of Xinjiang Uygur Autonomous Region, and the Qinghai, Gansu, and Sichuan Provinces. CONCLUSION: This study showed a serious prevalence of human echinococcosis with obvious spatial aggregation of the disease prevalence in China. The Qinghai-Tibet Plateau is the "hot spot" area of human echinococcosis in China. Findings from this study indicate that there is an urgent need of joint strategies to strengthen efforts for the prevention and control of echinococcosis in China, especially in the Qinghai-Tibet Plateau.

Smart deworming collar: A novel tool for reducing Echinococcus infection in dogs.

Echinococcosis is a serious zoonotic parasitic disease transmitted from canines to humans and livestock. Periodic deworming is recommended by the WHO/OIE as a highly effective measure against echinococcosis. However, manual deworming involves significant challenges, particularly in remote areas with scarce resources. The insufficient awareness delivering praziquantel (PZQ) baits for dogs leads to low compliance rate. The aim of this study was therefore to develop a novel smart collar for dogs to address these challenges. We developed a smart Internet of Things (IoT)-based deworming collar which can deliver PZQ baits for dogs automatically, regularly, quantitatively with predominant characteristics of being waterproof, anti-collision, cold-proof and long life battery. Its performance was tested in two remote locations on the Tibetan Plateau. A cross-sectional survey was conducted to evaluate the compliance of the dog owners. Further, a randomized controlled study was performed to evaluate the difference between smart-collar deworming and manual deworming. The collar's effectiveness was further assessed on the basis of Generalized Estimation Equations (GEE). The testing and evaluation was done for 10 smart deworming collars in factory laboratory, 18 collars attached for 18 dogs in Seni district, Tibet Autonomous Region, China, and 523 collars attached for 523 dogs in Hezuo city, Gansu province, China. The anti-collision, waterproof, and coldproof proportion of the smart collars were 100.0%, 99.5%, and 100.0%, respectively. When compared to manual deworming, the dogs' risk of infection with Echinococcus on smart-collar deworming is down to 0.182 times (95% CI: 0.049, 0.684) in Seni district and 0.355 (95%CI: 0.178, 0.706) in Hezuo city, the smart collar has a significant protective effect. The owners' overall compliance rate to attach the smart collars for their dogs was 89%. The smart deworming collar could effectively reduce the dogs' risk of infection with Echinococcus in dogs, significantly increase the deworming frequency and coverage and rapidly remove worm biomass in dogs. Thus, it may be a promising alternative to manual deworming, particularly in remote areas on the Tibetan Plateau.

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.

Mobile Phone Radiation: Its Efficacy as Protoscolicidals.

OBJECTIVE: There are different types of radiations, such as microwaves and mobile waves. Certain types of radiofrequency were evaluated in hydatid cyst ablation or as protoscolicidals. This study aimed to assess the influence of mobile waves on hydatid cyst protoscolices. METHODS: Hydatid cysts were collected from the slaughterhouse and transferred to the laboratory. The contents of the cysts were drained in sterile conditions and the protoscolices were rinsed three times with phosphate buffered saline. Equal volumes of protoscolex suspensions were aliquoted into similar tubes. Based on the distance of the samples from the mobile generation waves, the tubes containing the parasitic suspensions were classified into three groups, each of which was further categorised into nine subgroups according to the time of the radiation exposure. The subgroup with zero exposure time was considered the control. RESULTS: It was found that the mortality rate of the protoscolices increases as the distance of the sample from the wave-generation source decreases (p<0.0001). Increasing the time of exposure also improves the mortality rate of protoscolices. CONCLUSION: The mortality rate of protoscolices was directly proportional to the time of exposure and inversely proportional to the distance from the mobile generation waves.

A case for adoption of continuous albendazole treatment regimen for human echinococcal infections.

Cystic (CE) and alveolar (AE) echinococcosis are chronic, neglected parasitic diseases burdened by high morbidity and, for AE, by high mortality, if left untreated. CE and AE have a widespread distribution, including Europe. Albendazole (ABZ), a broad-spectrum benzimidazole drug widely used to treat parasitic infections, is the drug of choice for the management of CE and AE, and is parasitostatic on echinococcal metacestodes. In Europe, ABZ is licensed for interrupted "cyclic" treatment, for a maximum of 3 cycles. However, better efficacy with no increased side effects has been shown when the drug is administered continuously and for longer periods. Current international recommendations, on the basis of clinical, pharmacological, and biological studies, recommend continuous administration of ABZ for months to years for the treatment of CE and AE, and this schedule has been widely in use for the past 20 years. However, in Europe this internationally recommended schedule, with the exception of France, is technically "off-label", and, as such, requires an informed consent by the patient and, in some countries, even precludes the reimbursement of the drug cost. Adding to the very high cost of the drug, frequent "out-of-stock" situation, and packaging format impractical for long therapies, these conditions put patients with CE and AE regularly at risk of treatment discontinuation and disease progression. European regulations envisage variations to marketing authorization, but postauthorization studies should be carried out by the holder of the license of the drug, in the form of randomized controlled trials. While such studies do not seem feasible and would probably not be ethically justified for CE and AE, European regulations envisage other possibilities in particular situations, which apply to CE and AE, but there is limited interest to invest in this perspective. We urge a coordination between stakeholders to find effective and feasible ways to take action to revise the benzimidazole dosage regimens for CE and AE and to ensure a fair, regular, and easy access to the appropriate treatment to those suffering from these serious diseases.

Cystic echinococcosis in the Eastern Mediterranean region: Neglected and prevailing!

Cystic echinococcosis (CE) is distributed worldwide, extending from China to the Middle East and from Mediterranean countries to the sub-Saharan Africa and South America. According to WHO, one million people around the world are suffering from CE with an estimated burden of 183,573 DALYs. The annual monetary burden of the disease due to treatment costs and CE-related livestock losses has been estimated at US$ 3 billion. CE is endemic in all countries within the WHO Eastern Mediterranean Regional Office (EMRO). The region, which includes most of the Middle East and North Africa, is one of the most ancient foci of the domestic cycle of CE and is recognized as one of the major hotspots of CE. There are 22 countries in the EMRO, where about 688 million people are living at risk of CE. In many EMRO countries, little is known about CE epidemiology and transmission. WHO included echinococcosis in a list of 17 neglected tropical diseases (NTDs) and 12 neglected zoonotic diseases (NZDs). Accordingly, different regional offices of WHO organized several initiatives for CE control and prevention. WHO's Western Pacific regional office considered echinococcosis as one of the region's major health topics, and several preventive measures have been implemented in the American region with the support of Pan American Health Organization (PAHO) in Argentina, Peru, Uruguay, and Chile. Although CE is endemic in all 22 EMRO countries, surprisingly, CE is absent from the health topics list of diseases and conditions in this region. Therefore, CE clearly requires further attention in the WHO EMRO agenda, and the need for elaboration of specific measures for CE control is becoming apparent in EMRO countries, where substantial collaborations among the member states and WHO EMRO is of paramount importance. Major topics of collaborative activities include training programs and health communication on different aspects of CE control, analysis of CE burden, national and international surveillance and disease registry systems, technical support to promote epidemiological studies for collecting baseline data, cost-benefit analysis of control interventions, and intersectoral cooperation among the agriculture, veterinary, medical, and health sectors.

Efficacy and safety of Curcuma longa essential oil to inactivate hydatid cyst protoscoleces.

BACKGROUND: One of the most important ways to cure hydatid cysts is surgery. Today, available chemical drugs have shown severe complications during hydatid cyst surgery. Here we investigated theefficacy and safety of Curcuma longa (C. longa) essential oil (CLEO) against hydatid cysts protoscoleces. METHODS: Here, the collected protoscoleces from fertile hydatid cysts were exposed to different concentrations of the CLEO (50-200 µl/mL) for 5-30 min in vitro and ex vivo. In addition, male NIH mice (48 mice) were applied to examine the safety of CLEO. RESULTS: All protoscoleces were completely killed in 5th min of treatment to the doses of 200 µl /mL of CLEO. On the other hand, in the 10th min of treatment, CLEO entirely killed 100% of protoscoleces at the dose of 100 µL/mL. Other doses of CLEO, but, revealed a postponed activity. Although CLEO at the doses of 50, and 100 µL/mL exhibited no similar effect in the ex vivo analysis; but, at the dose of 200 µL/mL and an exposure time of 5 min, approximately 100% of protoscoleces were destroyed into the cyst. We found that after intra-peritoneal injection of the CLEO for 14 days, although blood and biochemical parameters were changed; but there was no significant difference in comparison with the control group (p > 0.05). CONCLUSION: This research demonstrated that C. longa revealed the promising scolicidal effects against protoscoleces in vitro and in vivo, of course, after additional tests; it might be considered as an herbal scolicidal drug in order to decrease the threat of discharge of protoscoleces through hydatid cyst surgery. Nevertheless, supplementary studies will be desired to prove the current findings by examination the essential oil in a clinical setting.

Childhood suffering: hyper endemic echinococcosis in Qinghai-Tibetan primary school students, China.

BACKGROUND: As part of an ongoing program that aims to use early detection and timely treatment to improve the control of echinococcosis, especially in younger age groups, we undertook a series of active surveys among Qinghai-Tibetan children in the Qinghai Province of Northwestern China in 2011 and 2012. The significant outcomes that resulted from this study emphasize the need to draw attention to echinococcosis, both alveolar echinococcosis (AE) and cystic echinococcosis (CE), so that policy development is promoted and suitable avenues for control are identified in the highly endemic areas on the Tibetan Plateau. METHODS: A total of 19 629 primary school students, aged 6-18 years, with a dominant Tibetan background underwent abdominal ultrasound examination, and 86.4% of the compliant students donated 2-5 ml of venous blood for serological tests. All the abnormal ultrasound results were recorded. If identified as echinococcosis, the disease lesion was assessed according to the WHO-Informal Working Group on Echinococcosis (WHO-IWGE) classification for AE and CE. Among the surveyed students, the prevalence by school was compared among geo-locations, sex and age groups. The clinical image presentations were analyzed according to lesion number, size, the location in the liver and the classification stage. Statistical significance was set at P-value < 0.05 for comparisons among groups. RESULTS: A total of 341 students (1.7%) were identified by ultrasound as having either CE (119, 0.6%) or AE (222, 1.1%). The highest prevalence rates of childhood AE cases occurred in the Tehetu (12.1%) and Moba (11.8%) townships in Dari County. There was a high seropositive rate (37.0%) and a heterogeneous distribution of cases, with a prevalence ranged from 0 to 12.1% for AE and 0-2.9% for CE. Moreover, the seropositive rate ranged from 0.7-45.1% across different schools. CONCLUSIONS: The high prevalence of echinococcosis in Qinghai-Tibetan primary school students reflects a lack of knowledge about Echinococcus spp. transmission. The combination of systematic education for children and regularly performed anthelmintic treatment for dogs could achieve the goal of sustainable hydatidosis control.

Echinococcus ortleppi, the cattle strain in a crested porcupine (Hystrix cristata): A new host record.

Echinococcus granulosus sensu lato, a dog tapeworm is a species complex causing cystic echinococcosis or hydatid disease in a great variety of mammalian intermediate hosts, including humans. This complex comprises five species including Echinococcus ortleppi (G5 genotype or cattle strain). In the present paper, we report the first case of infection with the larval stage of latter cestode in a captive crested porcupine (Hystrix cristata), molecularly confirmed by PCR and sequencing of the cox1 and nad1 genes. The food contaminated with the parasite's eggs is the most likely source of the infection. Our data broaden the knowledge on the host range and geographical distribution of this rarely reported species of Echinococcus in Europe.

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

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

[Echinococcosis hyper-endemic and cystic fertility in pigs of the inter-andean valley of Huancarama, Peru]. / Hiperendemia de equinococosis y fertilidad quística en porcinos del valle interandino de Huancarama, Perú.

The objective of the research was to determine the percentage of echinococcosis infection in swine, cystic fertility and associated factors. Cross-sectional study. The population was formed by 579 pigs slaughtered in the slaughterhouse of Huancarama. Hydatid cysts were detected by postmortem evaluation. Fertility was determined by measuring the diameter of the cysts and microscopically observing the germinative membrane in search of protoscoleces. The percentage of cystic echinococcosis infection was 76.7% (CI 95%: 73.2-80.3). Pigs older than two years were more likely to have cysts (RP 1.03; CI 95%: 1.0-1.1; (P < 0.01), as well as those coming from the Andahuaylas district (RP 1.2; CI 95%: 1.1-1.4; P < 0.01). Lung cysts showed a lower percentage of infection than hepatic ones. We examined 346 hydatid cysts of 334 pigs, a total fertility of 42.8% was found (CI 95%: 37.4-48.1).

El objetivo de la investigación fue determinar el porcentaje de infección de equinococosis en porcinos, fertilidad quística y factores asociados. Estudio de corte transversal. La población estuvo conformada por 579 porcinos faenados en el matadero de Huancarama. Los quistes hidatídicos fueron detectados mediante evaluación post mórtem. La fertilidad se determinó midiendo el diámetro de los quistes y observando microscópicamente la membrana germinativa en busca de protoescólices. El porcentaje de infección de equinococosis quística fue de 76,7% (IC95%: 73,2-80,3). Los porcinos mayores a dos años tuvieron más oportunidad de presentar quistes (RP 1,03; IC95%:1,0-1,1; p<0,01), al igual que los provenientes del distrito de Andahuaylas (RP 1,2; IC95%: 1,1-1,4; p<0,01). Los quistes pulmonares presentaron menor porcentaje de infección que los hepáticos. Se examinaron 346 quistes hidatídicos de 334 porcinos, se encontró una fertilidad total de 42,8% (IC95%: 37,4-48,1).

Systematic investigations of gene effects on both topologies and supports: An Echinococcus illustration.

In this paper, we propose a high performance computing toolbox implementing efficient statistical methods for the study of phylogenies. This toolbox, which implements logit models and LASSO-type penalties, gives a way to better understand, measure, and compare the impact of each gene on a global phylogeny. As an application, we study the Echinococcus phylogeny, which is often considered as a particularly difficult example. Mitochondrial and nuclear genomes (19 coding sequences) of nine Echinococcus species are considered in order to investigate the molecular phylogeny of this genus. First, we check that the 19 gene trees lead to 19 totally different unsupported topologies (a topology is the sister relationship when both branch lengths and supports are ignored in a phylogenetic tree), while using the 19 genes as a whole are not sufficient for estimating the phylogeny. In order to circumvent this issue and understand the impact of the genes, we computed 43,796 trees using combinations ranging from 13 to 19 genes. By doing so, 15 topologies are obtained. Four particular topologies, appearing more robust and frequent, are then selected for more precise investigation. Refining further our statistical analysis, a particularly robust topology is extracted. We also carefully demonstrate the influence of nuclear genes on the likelihood of the phylogeny.

The impact of socio-cultural factors on transmission of Taenia spp. and Echinococcus granulosus in Kosovo.

Echinococcus granulosus sensu latu (s.l.) and Taenia hydatigena are common parasites of ruminant intermediate hosts in the Balkans. Transmission is linked mainly to home slaughtering and the feeding of infected organs to dogs. In Kosovo, many old sheep are slaughtered particularly during Eid al-Adha (Feast of Sacrifice). To determine whether this tradition could affect parasite transmission, we compared the probability of 504 dogs to contract taenid infections after deworming during one period before Eid al-Adha and a similar period beginning with this event. Initially, taeniid eggs were detected in 6·2% (CI 4·2-8·6) of the dogs. The prevalence before Eid al-Adha was significantly lower (1·2%, CI 0·4-2·6) as compared with the prevalence after the event (4·3%, CI 2·6-6·3). A comparable trend was apparent at species level for T. hydatigena and E. granulosus. These results indicate that the pronounced increase of taeniid infections, including E. granulosus s.l., after Eid al-Adha is linked to traditional home slaughtering that occurs during this celebration. This particular epidemiological situation provides an opportunity for implementing focussed control activities.

Tubercular infection of hydatid cyst.

Tubercular infection of hydatid cyst of the chest wall in an immunocompetent individual is rare. Immune modulation for symbiosis between host cells and the parasite - Echinococcus granulosus favors tubercular infection. In this case report, we describe a case of both these chronic diseases coexisting together, to present as chest wall mass.

Hiperendemia de equinococosis y fertilidad quística en porcinos del valle interandino de Huancarama, Perú / Echinococcosis hyper-endemic and cystic fertility in pigs of the inter-andean valley of Huancarama, Peru

El objetivo de la investigación fue determinar el porcentaje de infección de equinococosis en porcinos, fertilidad quística y factores asociados. Estudio de corte transversal. La población estuvo conformada por 579 porcinos faenados en el matadero de Huancarama. Los quistes hidatídicos fueron detectados mediante evaluación post mórtem. La fertilidad se determinó midiendo el diámetro de los quistes y observando microscópicamente la membrana germinativa en busca de protoescólices. El porcentaje de infección de equinococosis quística fue de 76,7% (IC95%: 73,2-80,3). Los porcinos mayores a dos años tuvieron más oportunidad de presentar quistes (RP 1,03; IC95%:1,0-1,1; p<0,01), al igual que los provenientes del distrito de Andahuaylas (RP 1,2; IC95%: 1,1-1,4; p<0,01). Los quistes pulmonares presentaron menor porcentaje de infección que los hepáticos. Se examinaron 346 quistes hidatídicos de 334 porcinos, se encontró una fertilidad total de 42,8% (IC95%: 37,4-48,1).

The objective of the research was to determine the percentage of echinococcosis infection in swine, cystic fertility and associated factors. Cross-sectional study. The population was formed by 579 pigs slaughtered in the slaughterhouse of Huancarama. Hydatid cysts were detected by postmortem evaluation. Fertility was determined by measuring the diameter of the cysts and microscopically observing the germinative membrane in search of protoscoleces. The percentage of cystic echinococcosis infection was 76.7% (CI 95%: 73.2-80.3). Pigs older than two years were more likely to have cysts (RP 1.03; CI 95%: 1.0-1.1; (P < 0.01), as well as those coming from the Andahuaylas district (RP 1.2; CI 95%: 1.1-1.4; P < 0.01). Lung cysts showed a lower percentage of infection than hepatic ones. We examined 346 hydatid cysts of 334 pigs, a total fertility of 42.8% was found (CI 95%: 37.4-48.1).

Historical Aspects of Echinococcosis.

Echinococcosis is a zoonosis whose history dates back to antiquity. This article provides an overview on the general history of echinococcosis, including the elucidation of Echinococcus life cycles and the long controversy on the aetiology of the cystic and alveolar forms of echinococcosis (CE and AE), lasting about 100years since the middle of the 19th century. Furthermore, selected historical aspects of some fields of echinococcosis research are discussed and compared with our current knowledge, such as geographic distribution and epidemiology of CE (Echinococcus granulosus) and AE (Echinococcus multilocularis), clinical aspects and pathology, diagnosis in humans and animals, treatment (with focus on chemotherapy), control and basic research. A short paragraph is devoted to the neotropical forms of echinococcosis, caused by Echinococcus vogeli and Echinococcus oligarthrus. In this context the achievements of some ancestral pioneers of echinococcosis research are particularly highlighted and appreciated. Finally, the role of associations, international organizations (World Health Organization and others) and international working groups in echinococcosis research and control is briefly outlined. The retrospective reveals both the admirable achievements of our ancestors and the scientific progress of more recent times. But, it also shows the gaps in our knowledge, skills and resources that we need to control or even eradicate echinococcosis.

Ecology and Life Cycle Patterns of Echinococcus Species.

The genus Echinococcus is composed of eight generally recognized species and one genotypic cluster (Echinococcus canadensis cluster) that may in future be resolved into one to three species. For each species, we review existing information on transmission routes and life cycles in different geographical contexts and - where available - include basic biological information of parasites and hosts (e.g., susceptibility of host species). While some Echinococcus spp. are transmitted in life cycles that involve predominantly domestic animals (e.g., dog - livestock cycles), others are wildlife parasites that do or do not interact with domestic transmission. In many cases, life cycle patterns of the same parasite species differ according to geography. Simple life cycles contrast with transmission patterns that are highly complex, involving multihost systems that may include both domestic and wild mammals. Wildlife transmission may be primary or secondary, i.e., resulting from spillovers from domestic animals. For most of the species and regions, existing information does not yet permit a conclusive description of transmission systems. Such data, however, would be highly relevant, e.g., for anticipation of geographical changes of the presence and frequency of these parasites in a warming world, or for initiating evidence-based control strategies.