Incidence Of Alveolar Echinococcosis Research Articles

Environmental distribution of Echinococcus- and Taenia spp.-contaminated dog feces in Kyrgyzstan.

Recently, there have been epidemics of human cystic echinococcosis (CE) and alveolar echinococcosis (AE) in Kyrgyzstan. This study investigated 2 districts for the presence of Echinococcus granulosus s.l. and Echinococcus multilocularis eggs; species identity was confirmed by polymerase chain reaction in dog feces and the level of environmental contamination with parasite eggs in 2017–2018 was also investigated. In the Alay district 5 villages with a high reported annual incidence of AE of 162 cases per 100 000 and 5 villages in the Kochkor district which had a much lower incidence of 21 cases per 100 000 were investigated. However, the proportion of dog feces containing E. granulosus s.l. eggs was ~4.2 and ~3.5% in Alay and Kochkor respectively. For E. multilocularis, the corresponding proportions were 2.8 and 3.2%. Environmental contamination of Echinococcus spp. eggs was estimated using the McMaster technique for fecal egg counts, weight and density of canine feces. The level of environmental contamination with E. multilocularis eggs was similar at 4.4 and 5.0 eggs per m2 in Alay and Kochkor respectively. The corresponding values for E. granulosus s.l. were 8.3 and 7.5 eggs per m2. There was no association between village or district level incidence of human AE or CE and the proportion of dog feces containing eggs of Echinococcus spp. or the level of environmental contamination. Increased contamination of taeniid eggs occured in the autumn, after the return of farmers with dogs from summer mountain pastures.

Epidemiology of human alveolar echinococcosis in Armenia

Abstract Background Since the 90s' E.multilocularis infection in foxes is rising and central-eastern European countries had seen first Alveolar echinococcosis (AE) human cases. AE is considered to be a very rare disease in Europe with average incidences of 0.03-0.20/100,000 inhabitants/year. Because of a suitable orography, this study aims to confirm whether there are human AE cases in Armenia, identify areas at risk, and also estimate AE annual incidence. Methods Retrospective AE case finding was carried out at main 6 multi-profile medical centers equipped with the most innovative diagnostic means. The medical records of all patients with liver surgery admitted between January 2008 and June 2020 were reviewed. A specific form was developed in EpiInfo v. 7.2. Annual national incidence was estimated using population denominators provided by the National Institute of Statistics (the population of Armenia is estimated at 2 963 243 people). Results From September 2019 until June 2020, overall 11 AE cases have been identified. All patients were diagnosed at advanced stages, with subsequent poor prognosis and costly treatment. Confirmation was based on tissue biopsy results. Age ranged from 19-59 years with a median of 39yrs. E. multilocularis was detected in rural communities, mostly in the Gegharkunik region (6 cases, 55%). Annual average incidence of AE was 0.033 varying between 0.032 in 2008 and 0.1 in 2017. For comparison with Armenia, an annual incidence in France was 0.026/100,000 in 2008 (the population of France is estimated at 65 273 511 people). Conclusions All cases were not notified by the surveillance system and the real prevalence of AE in the country is unknown. This young age could indicate widespread of infection in animals. Therefore, the burden of AE disease is difficult to estimate. The surveillance system in Armenia can be improved by the development of national guidelines for the prospective registry, AE awareness campaigns. Key messages First-time identification of human AE in Armenia calls for implementation of surveillance with a case definition and registry of all cases. AE is an emerging, and so far silent threat in Armenia.

Incidence of alveolar echinococcosis in humans and animals in Kostanay region of the Republic of Kazakhstan

The research aims to study the spread of alveococcosis in humans and animals on the territory of the Kostanay region of the Republic of Kazakhstan. Studies on the diagnosis of alveococcosis in humans were conducted in the branch of the Ministry of Health of the Republic of Kazakhstan "Scientific-practical center of sanitary-epidemiological examination and monitoring", Kostanay, in 2010-2019. To determine the degree of invasion by alveococcosis, a pathoanatomic autopsy was performed on captured mouse-like rodents in the territory of the Kostanay region, where cases of human alveococcosis were registered. The incidence among the population of various age groups in the region was analyzed based on the results of blood samples by enzyme immunoassay (ELISA) and liver ultrasound. It is established that alveococcosis is a common disease among people living not only in the Kostanay region but also in the Republic of Kazakhstan in general. The main definitive hosts in the development cycle of the pathogen infestation on the territory of the Republic of Kazakhstan are foxes and dogs, intermediate hosts – 18 species of rodents, and for humans, alveococcosis is one of the most dangerous helminthic diseases, since in most cases it leads to death. Alveococcosis can be attributed to particularly dangerous infestations since the foci of infestation are formed not only in anthropogenic zones where the pathogen can devastate but also in natural biocenoses, where the main sources of the pathogen's spread in the external environment are foxes (Vulpes) and corsac foxes (Vulpes corsac). The maximum number of cases of alveococcosis in 2018-2020 was registered in intermediate hosts – mouse-like rodents, like common vole Microtus arvalis, the extent of A. multilocularis invasion was 3.1-3.5%. Based on the comparative analysis of the epizootic and epidemiological situation of alveococcosis in the territory of the Kostanay region, it should be noted that the risk of infection of the population with alveococcosis persists in all areas of the region.

Elevated incidence of alveolar echinococcosis in immunocompromised patients

IntroductionRecent experimental data has revealed that the course of alveolar echinococcosis (AE) depends on adaptive immunity. For this study, we aimed to analyze the incidence and outcome of AE in immunocompromised humans. Material and methodsRetrospective analysis of 131 patients with a median age of 54 years treated for AE between 1971 and 2017 at a Swiss tertiary referral Centre. Fifty-two percent were females and 65 patients (50%) were diagnosed incidentally. Fourteen patients (16%) were operated on laparoscopically. Overall, median follow-up was 48 months. ResultsNew diagnoses have increased fourfold in immunocompetent and tenfold in immunocompromised patients in the past decade (p ≤ 0.005). Forty-one patients (31.3%) had co-existing or previous immunosuppressive conditions including 16 malignancies (36%), 11 auto-immune diseases or immunosuppressive therapies (31%), 5 infectious diseases (11%), 4 chronic asthma conditions (9%), 2 previous transplantations (4%) and 4 other immunocompromising conditions (9%). Serum levels of anti-Em18, −Em2 and -EgHF antibodies were neither associated with immunocompetence at diagnosis nor during follow-up, but significantly decreased after treatment with benzimidazole (n = 43) or surgery (n = 88) in all patients. Adjuvant therapy for ≥1 year (p = 0.007) with benzimidazole and resection status (R0) (p = 0.002) were both correlated with recurrence-free survival. Survival at 5 and 10 years after surgery was 97% and 94%, respectively, and after conservative treatment 91% and 73%, respectively. Curative surgery (p = 0.014) and immunocompetence (p = 0.048) correlated significantly with overall survival. ConclusionThe incidence of human AE has increased over the last 2 decades with surgical interventions resulting in excellent outcomes. We have observed an association of immunosuppressive conditions with both incidence and survival of AE eventually justifying the implementation of a screening program for patients at risk in endemic regions.

Human cystic and alveolar echinococcosis in the Tibet Autonomous Region (TAR), China.

Human cystic echinococcosis (CE) is known to be endemic in the Tibet Autonomous Region (TAR), China; however, there is relatively little data from hospital records or community prevalence studies, and the situation regarding occurrence of human alveolar echinococcosis (AE) is unclear. Here we review the available reports about human echinococcosis in the seven prefectures of TAR. In addition, two pilot studies by mass screening using ultrasound (with serology) were undertaken (2006/7) in Dangxiong County of Lhasa Prefecture (north central TAR) and Dingqing County of Changdu Prefecture (eastern TAR). In Dangxiong County a prevalence of 9.9% (55/557) for human CE was obtained but no human AE cases were detected. By contrast, in Dingqing County (N= 232 persons screened), 11 CE cases (4.7%) and 12 AE cases (5.2%) (including one mixed CE and AE case) were diagnosed by ultrasound. Hospital records and published reports indicated that CE cases were recorded in all of seven prefectures in Tibet Autonomous Region, and AE cases in four prefectures. Incidence rates of human CE were estimated to range from 1.9 to 155 per 100,000 across the seven prefectures of TAR, with a regional incidence of 45.1 per 100,000. Incidence of AE was estimated to be between 0.6 and 2.8 cases per 100,000. Overall for TAR, human AE prevalence appeared relatively low; however, the pilot mass screening in Dingqing in eastern TAR indicated that human AE disease is a potential public health problem, possibly similar to that already well described in Tibetan communities bordering TAR in north-west Sichuan and south-west Qinghai provinces.

Human Alveolar Echinococcosis after Fox Population Increase, Switzerland

We analyzed databases spanning 50 years, which included retrospective alveolar echinococcosis (AE) case finding studies and databases of the 3 major centers for treatment of AE in Switzerland. A total of 494 cases were recorded. Annual incidence of AE per 100,000 population increased from 0.12-0.15 during 1956-1992 and a mean of 0.10 during 1993-2000 to a mean of 0.26 during 2001-2005. Because the clinical stage of the disease did not change between observation periods, this increase cannot be explained by improved diagnosis. Swiss hunting statistics suggested that the fox population increased 4-fold from 1980 through 1995 and has persisted at these higher levels. Because the period between infection and development of clinical disease is long, the increase in the fox population and high Echinococcus multilocularis prevalence rates in foxes in rural and urban areas may have resulted in an emerging epidemic of AE 10-15 years later.

Human alveolar echinococcosis in Slovenia

Between January 2001 and December 2005, 1263 patients suspected of having echinococcosis were screened serologically by indirect haemagglutination assay (IHA). IHA-positive patient sera were then retested by western blot for confirmation and differentiation between Echinococcus granulosus and Echinococcus multilocularis infection. Of 43 sera confirmed as Echinococcus-positive, nine appeared to be specific for alveolar echinococcosis (AE) caused by E. multilocularis. AE-positive serological results corresponded to the clinical and/or imaging findings concerning the patients' liver cysts. The detected incidence of AE was 0.45/10(5) inhabitants, which suggests that clinicians and health authorities in Slovenia should give greater attention to AE in the future.

Echinococcosis, Ningxia, China

Echinococcosis, Ningxia, China

Prevention of alveolar echinococcosis—ecosystem and risk management perspectives in Japan

We focused on the epidemiology of alveolar echinococcosis especially in Japan and discussed control measures to prevent an epidemic. No effective control measures against alveolar echinococcosis have been identified thus far because it is difficult to fully understand the ecology of the parasite and its hosts, i.e. the precise infection route to humans. In Hokkaido, Japan, infection rates among red foxes have recently risen even in low endemic districts. Infection seems to be spreading not only among wild foxes but also among domestic dogs. Despite only sporadic reports of human cases in Japan, we predict that the incidence of alveolar echinococcosis will increase in the near future if no effective preventive measures are put in place. An Echinococcus multilocularis epidemic would have the potential to affect the economy of Hokkaido, due to its impact on the agricultural and tourist industries. Well-designed epidemiological surveys are, therefore, urgently required prior to large outbreaks, based on understanding of the ecosystem around E. multilocularis.

Die chirurgische Therapie der alveolären Echinokokkose und deren Langzeitergebnisse

The incidence of alveolar echinococcosis (AE) is low, and studies and progress reports with regard to surgical procedures are rare. Retrospective analysis of surgical therapy of AE and its long-term results between 1983 and 2000 by evaluating medical records and questionnaires. German university hospital within the endemic area. Twenty-five surgical procedures were performed in 19 patients with AE (12x partial resection of the liver, 3 of them with additional extrahepatic resection; 3x just extrahepatic resection, 4x bilidigestive anastomosis, 5x exploratory laparotomy, 1x bypass procedure). Fifteen patients were operated on the first time with that diagnosis, four due to a relapse. Seven surgical procedures were estimated to be curative, whereas 18 were palliative, because the parasitic mass could not be resected in toto. One patient died from persistent systemic sepsis as a consequence of microbial superinvasion of a splenic parasitic mass. Morbidity was 28%. All patients had additional medical treatment and periodic follow-up. Three of seven patients estimated for curative surgery developed a relapse. One of the patients discharged following palliative surgery died 13 years after diagnosis with liver insufficiency. Advances in conservative and interventional treatments have greatly improved the prognosis of the disease. Curative surgery for AE is feasible only in a minority of patients, because frequently the disease has already spread widely when diagnosed. The minimum distance between the lesion and the cut surface should be 2 cm. Taking the advances in conservative treatment into consideration, the benefit of palliative surgery is uncertain and today there is no evidence for prolonged survival by palliative surgical procedures. Palliative surgery should therefore be reserved for cases with complications that could not be managed by conservative and interventional treatment.