Prevalence of human cystic echinococcosis in the towns of Ñorquinco and Ramos Mexia in Rio Negro Province, Argentina, and direct risk factors for infection.

BACKGROUND: Cystic echinococcosis (CE) is a parasitic zoonosis caused by infection with the larval stage of Echinococcus granulosus (s.l.). This study investigated the prevalence and potential risk factors associated with human CE in the towns and rural areas of Ñorquinco and Ramos Mexia, Rio Negro province, Argentina. METHODS: To detect abdominal CE cysts, we screened 892 volunteers by ultrasound and investigated potential risk factors for CE using a standardized questionnaire. Prevalence ratio (PR) with 95% confidence intervals (CI) was used to measure the association between CE and the factors investigated, applying bivariate and multivariate analyses. RESULTS: Abdominal CE was detected in 42/892 screened volunteers (4.7%, 95% CI 3.2-6.1), only two of whom were under 15 years of age. Thirteen (30.9%) CE cases had 25 cysts in active stages (CE1, CE2, CE3a, according to the WHO Informal Working Group on Echinococcosis [WHO-IWGE] classification). The most relevant risk factors identified in the bivariate analysis included: living in rural areas (P = 0.003), age > 40 years (P = 0.000), always drinking water from natural sources (P = 0.007), residing in rural areas during the first 5 years of life (P = 0.000) and having lived more than 20 years at the current address (P = 0.013). In the multivariate final model, the statistically significant risk factors were: frequently touching dogs (P = 0.012), residing in rural areas during the first 5 years of life (P = 0.004), smoking (P = 0.000), age > 60 years (P = 0.002) and living in rural areas (P = 0.017). CONCLUSIONS: Our results point toward infection with CE being acquired since childhood and with constant exposure throughout life, especially in rural areas with a general environmental contamination.

First report of cystic echinococcosis caused by Echinococcus granulosus sensu stricto/G1 in Felis catus from the Patagonian region of Argentina.

Two domestic cats from the Patagonia rural area in Argentina were found to be naturally infected with Echinococcus granulosus sensu stricto/G1 genotype; so far, the only species/genotype of E. granulosus sensu lato complex described to infect domestic cats. The felines developed abdominal disseminated larval disease; the diagnosis was performed by ultrasound, exploratory laparotomy, and molecular techniques. These results indicate that cystic echinococcosis must be considered for differential diagnosis of felines with abdominal distension and/or observation of vesicles through ultrasound, from endemic areas. Even though cats and dogs are carnivores, differences in digestive physiology and immunological characteristics between them could allow the development of larval or adult worm parasites. Domestic cats with cystic echinococcosis show to be environmentally infected with E. granulosus s. s./G1 eggs.

Enduring Challenge of Invasive Ticks: Introduction of Amblyomma oblongoguttatum (Acari: Ixodidae) into the United States on a Human Traveler Returning from Central America.

Introduction of exotic tick vectors of bacteria, protozoa, viruses, and filarial parasites into the United States has accelerated in recent years, primarily because of globalization, increased frequency of travel, and a rise in legal and illegal animal trades. We herein report introduction of a live specimen of Amblyomma oblongoguttatum on a human into the United States from Central America, and we review 4 previous similar incidents. This tick species occurs widely in the neotropics, from western and southern Mexico, southwards through Central America, to the northern half of South America. It is a potential vector of bacterial agents of spotted fever group rickettsioses, raising concern that if A. oblongoguttatum ticks become established in this country, they might also be able to carry pathogens of human and veterinary concern. Given the potential for exotic ticks as vectors of numerous pathogens, proper surveillance, interception, and identification of these ticks are vital to protecting human and veterinary health. Rigorous governmental inspections of imported livestock and pet animals at ports of entry and educating human travelers and medical practitioners about the risks should be part of an overall national tick program.

First report in pre-Columbian mummies from Bolivia of Enterobius vermicularis infection and capillariid eggs: A contribution to Paleoparasitology studies.

OBJECTIVE: This study was designed to search for ancient parasites in abdominal content and coprolites from Bolivian mummies. MATERIALS: Twelve mummified individuals from the Andean highlands, housed at the National Museum of Archaeology (MUNARQ) in La Paz, Bolivia. METHODS: Microscopic analysis of rehydrated samples (coprolites and abdominal content), following Lutz's spontaneous sedimentation technique. RESULTS: Eggs of Enterobius vermicularis were identified in coprolites from one mummy, and capillariid eggs in the organic abdominal content from another individual. CONCLUSIONS: This is the first evidence of ancient intestinal parasites in Bolivian mummies. SIGNIFICANCE: This pioneering study focused on the search of ancient intestinal parasites in human remains of the Bolivian Andes and contributes to greater knowledge of paleoparasitology in South America. LIMITATIONS: All mummies in the MUNARQ belonged to the Andean Bolivian highlands (post-Tiwanaku era or Late Intermediate Period), although the exact provenance of the material and the associated contexts are not well recorded. SUGGESTIONS FOR FURTHER RESEARCH: Considering the great number of well-known archaeological sites and other unexplored sites in Bolivia, in addition to large collections in museums, further paleopathological and paleoparasitological molecular studies in mummies and skeletons are called for.

Bacterial diversity associated with the abdomens of naturally Plasmodium-infected and non-infected Nyssorhynchus darlingi.

BACKGROUND: The bacterial community present in the abdomen in Anophelinae mosquitoes can influence mosquito susceptibility to Plasmodium infection. Little is known about the bacteria associated with Nyssorhynchus darlingi, a primary malaria vector in the Amazon basin. We investigated the abdominal bacterial community compositions of naturally Plasmodium-infected (P-positive, n = 9) and non-infected (P-negative, n = 7) Ny. darlingi from the Brazilian Amazon region through massive parallel sequencing of the bacterial V4 variable region of the 16S rRNA gene. RESULTS: Bacterial richness of Ny. darlingi encompassed 379 operational taxonomic units (OTUs), the majority of them belonging to the Proteobacteria, Firmicutes and Bacteroides phyla. Escherichia/Shigella and Pseudomonas were more abundant in the P-positive and P-negative groups, respectively, than in the opposite groups. Enterobacter was found only in the P-negative group. The results of statistical analyses conducted to compare bacterial abundance and diversity between Plasmodium-infected and Plasmodium-non-infected mosquitoes were not significant. CONCLUSIONS: This study increased knowledge about bacterial composition in Ny. darlingi and revealed that Plasmodium-positive and Plasmodium-negative groups share a common core of bacteria. The genera Prevotella 9, Sphingomonas, Bacteroides, and Bacillus were reported for the first time in Ny. darlingi.

Morphological analysis reveals the presence of Hepatoxylon trichiuri (Holten, 1802) Bosc, 1811 (Cestoda: Sphyriocephalidae) in Lepidopus caudatus (Euphrasen, 1788) (Pisces: Trichiuridae) from the Mediterranean Sea.

In this article, we report for the first time the presence of the parasite Hepatoxylon trichiuri in specimens of Lepidopus caudatus from the Mediterranean Sea. A total of four plerocercoids were studied using microscopy techniques for both morphological and histological analysis. RESEARCH HIGHLIGHTS: We report for the first time for the Mediterranean Sea the presence of the parasite Hepatoxylon trichiuri in specimens of the commercial fish species Lepidopus caudatus. The plerocercoids of H. trichiuri not seems cause observable illness in the fish. However, further studies are needed in order to better assess the incidence and prevalence of the parasite in L. caudatus and other fish species of commercial interest.

Epidemiological factors associated with human cystic echinococcosis: a semi-structured questionnaire from a large population-based ultrasound cross-sectional study in eastern Europe and Turkey.

BACKGROUND: Cystic echinococcosis (CE) is a neglected parasitic zoonosis prioritized by the WHO for control. Several studies have investigated potential risk factors for CE through questionnaires, mostly carried out on small samples, providing contrasting results. We present the analysis of risk factor questionnaires administered to participants to a large CE prevalence study conducted in Bulgaria, Romania and Turkey. METHODS: A semi-structured questionnaire was administered to 24,687 people from rural Bulgaria, Romania and Turkey. CE cases were defined as individuals with abdominal CE cysts detected by ultrasound. Variables associated with CE at P < 0.20 in bivariate analysis were included into a multivariable logistic model, with a random effect to account for clustering at village level. Adjusted odds ratios (AOR) with 95% CI were used to describe the strength of associations. Data were weighted to reflect the relative distribution of the rural population in the study area by country, age group and sex. RESULTS: Valid records from 22,027 people were analyzed. According to the main occupation in the past 20 years, "housewife" (AOR: 3.11; 95% CI: 1.51-6.41) and "retired" (AOR: 2.88; 95% CI: 1.09-7.65) showed significantly higher odds of being infected compared to non-agricultural workers. "Having relatives with CE" (AOR: 4.18; 95% CI: 1.77-9.88) was also associated with higher odds of infection. Interestingly, dog-related and food/water-related factors were not associated with infection. CONCLUSIONS: Our results point toward infection being acquired in a "domestic" rural environment and support the view that CE should be considered more a "soil-transmitted" than a "food-borne" infection. This result helps delineating the dynamics of infection transmission and has practical implications in the design of specific studies to shed light on actual sources of infection and inform control campaigns.

Case Report: Rare Presentation of Multivisceral Echinococcosis.

Cystic echinococcosis (CE) is a common, chronic, and endemic zoonotic disease usually localized in a single organ; multivisceral cases are rare, especially outside the liver or lung. Here, we describe an unusual case of a 43-year-old Tibetan man with echinococcosis of the infratemporal fossa, heart, liver, pancreas, abdomen, and pelvic cavity. He only presented with diminished vision of the left eye, especially when chewing. Computed tomography and magnetic resonance imaging revealed multivisceral CE. The patient underwent surgery for the excision of a cyst in the infratemporal fossa, as well as chemotherapy, and the diagnosis was confirmed by histopathological examination. The diagnosis, clinical features, treatment, and follow-up in this case are discussed. In areas with high echinococcosis prevalence, examination by full imaging is necessary for an accurate diagnosis, especially in cases of atypical localization. Chemotherapy for treatment, as well as prophylaxis against recurrence, can be effective when surgery is not possible.

Case Report: Percutaneous Treatment of Multiple Echinococcal Cysts Presenting as Abdominal Palpable Mass.

We report the case of an adolescent Moroccan girl with abdominal pain and palpable mass in the upper right side of the abdomen. In the emergency department, an abdominal ultrasound showed hepatomegaly and eight active liver cysts, compatible with cystic echinococcosis. Serology for Echinococcus granulosus confirmed the diagnosis. Other sites of localization were excluded. Treatment involved albendazole combined with puncture, aspiration, injection, re-aspiration, performed only for the most medial cysts. Periodical follow-up with abdominal ultrasound and with abdominal magnetic resonance imaging showed a progressive involution of all cysts. The treatment with albendazole was stopped after, overall, 6 months, and monthly ultrasound scan were planned as follow-up. In case of hepatic cysts, E. granulosus should be excluded, especially in children from endemic countries. A multidisciplinary approach with pediatric infectious disease specialists, radiologists, and surgeons is fundamental for disease management.

Biliary Taeniasis with Cholecystitis: An Unusual Case of Taenia solium Infection with a Literature Review.

Taeniasis is a cosmopolitan helminthic disease caused by Taenia species, which included Taenia solium, Taenia saginata, and Taenia asiatica. These parasites typically infect the small intestine, but cases of aberrant migration have been reported. We treated a 70-year-old man who presented with vomiting and colicky abdominal pain. On physical examination, Murphy's sign was positive, and laboratory findings indicated severe inflammation. Computed tomography and magnetic resonance cholangiopancreatography revealed typical features of cholecystitis. An 82-cm-long, slender and degenerated, parasite-like organism was aspirated through a percutaneous transhepatic gallbladder drainage tube. After extensive washing of the organism, we detected yellowish-brown colored, spherical 37.9 × 33.8-µm-sized taenid eggs with thick transverse striations. Hematoxylin-eosin-stained worm sections also contained Taeniidae eggs. Polymerase chain reaction amplification of DNA extracted from the worm with species-specific cytochrome c1 (cox1) primer sets detected a T. solium-specific fragment. Because of sustained high fever combined with inflammatory signs, the patient underwent laparoscopic cholecystectomy and inflamed gallbladder removal. A histopathologic specimen demonstrated chronic reactive cholecystitis. The patient's fever and leukocytosis rapidly resolved after surgery. We experienced an uncommon case of biliary taeniasis representing cholecystitis caused by adult worm of T. solium.

Cystic echinococcosis in a domestic cat (Felis catus) in Italy.

Echinococcus granulosus sensu lato is a zoonotic agent with a life cycle consisting of definitive hosts (dogs and wild carnivores), and intermediate hosts (usually ungulates). Other animals and humans may accidentally ingest eggs and contract cystic echinococcosis, acting as aberrant hosts. A 3-year-old neutered female cat was brought to a veterinary practice in Sassari (Italy) with abdominal distension. Ultrasound showed multiple intraperitoneal vesicles, which on laparotomy were found to be metacestodes of E. granulosus. Videos of the extraction of cysts are provided. Phylogenetic analysis based on a fragment of the cytochrome oxidase subunit 1 (cox1) mitochondrial gene identified the isolate as E. granulosus sensu stricto genotype G1, the most common genotype circulating in Europe and the Mediterranean basin. This is the first case report of cystic echinococcosis in domestic cats from Italy.

Expression of matrix metalloproteinase-2 and metalloproteinase-9 in the skin of dogs with visceral leishmaniasis.

The skin is the first organ to be infected by the parasite in canine visceral leishmaniasis. The enzyme matrix metalloproteinase (MMP) acts towards degradation of the extracellular matrix (ECM) and modulation of the inflammatory response against many kinds of injuries. The aims of this study were to evaluate the expression of MMP-2 and MMP-9 through immunohistochemistry and zymography on the skin (muzzle, ears, and abdomen) of dogs that were naturally infected by Leishmania spp. and to compare these results with immunodetection of the parasite and with alterations to the dermal ECM. Picrosirius red staining was used to differentiate collagen types I and III in three regions of the skin. The parasite load, intensity of inflammation, and production of MMP-2 (latent) and MMP-9 (active and latent) were higher in the ear and muzzle regions. MMP-9 (active) predominated in the infected group of dogs and its production was significantly different to that of the control group. Macrophages, lymphocytes, and plasma cells predominated in the dermal inflammation and formed granulomas in association with degradation of mature collagen (type I) and with discrete deposition of young collagen (type III). This dermal change was more pronounced in dogs with high parasite load in the skin. Therefore, it was concluded that the greater parasite load and intensity of inflammation in the skin led consequently to increased degradation of mature collagen, caused by increased production of MMPs, particularly active MMP-9, in dogs with visceral leishmaniasis. This host response profile possibly favors systemic dissemination of the parasite.

Hidden biodiversity in entomological collections: The overlooked co-occurrence of dipteran and hymenopteran ant parasitoids in stored biological material.

Biological collections around the world are the repository of biodiversity on Earth; they also hold a large quantity of unsorted, unidentified, or misidentified material and can house behavioral information on species that are difficult to access or no longer available to science. Among the unsorted, alcohol-preserved material stored in the Formicidae Collection of the 'El Colegio de la Frontera Sur' Research Center (Chetumal, Mexico), we found nine colonies of the ponerine ant Neoponera villosa, that had been collected in bromeliads at Calakmul (Campeche, Mexico) in 1999. Ants and their brood were revised for the presence of any sign of parasitism. Cocoons were dissected and their content examined under a stereomicroscope. Six N. villosa prepupae had been attacked by the ectoparasitoid syrphid fly Hypselosyrphus trigonus Hull (Syrphidae: Microdontinae), to date the only known dipteran species of the Microdontinae with a parasitoid lifestyle. In addition, six male pupae from three colonies contained gregarious endoparasitoid wasps. These were specialized in parasitizing this specific host caste as no gyne or worker pupae displayed signs of having been attacked. Only immature stages (larvae and pupae) of the wasp could be obtained. Due to the long storage period, DNA amplification failed; however, based on biological and morphological data, pupae were placed in the Encyrtidae family. This is the first record of an encyrtid wasp parasitizing N. villosa, and the second example of an encyrtid as a primary parasitoid of ants. Furthermore, it is also the first record of co-occurrence of a dipteran ectoparasitoid and a hymenopteran endoparasitoid living in sympatry within the same population of host ants. Our findings highlight the importance of biological collections as reservoirs of hidden biodiversity, not only at the taxonomic level, but also at the behavioral level, revealing complex living networks. They also highlight the need for funding in order to carry out biodiversity inventories and manage existing collections.

Prevalence and Risk Factors for Human Cystic Echinococcosis in the Cusco Region of the Peruvian Highlands Diagnosed Using Focused Abdominal Ultrasound.

AbstractLatin America is among the highly endemic regions for cystic echinococcosis (CE). In Peru, an estimated 1,139 disability-adjusted life years are lost annually from surgical treatment of CE. This is comparable with the combined total for Argentina, Brazil, Uruguay, and Chile. The prevalence of human infection has been investigated in the central Peruvian Andes, but there are no community-based screening data from other regions of Peru. We carried out a population survey in January 2015 using abdominal ultrasound to estimate the prevalence of abdominal CE in the Canas and Canchis provinces, in the Cusco region of Peru. Among 1,351 subjects screened, 41 (3%) had CE. There was significant variation between communities with similar socioeconomic features in a small geographical area. A history of CE was reported by 4.1% of the screened subjects, among whom 30.3% still had CE on ultrasound. Among patients reporting previous CE treatment, 14.9% had CE in active stages. Limited education, community of residence, and knowing people with CE in the community were associated with CE. These results demonstrate a significant burden of CE in the region and suggest the need for further investigations, control activities, and optimization of clinical management for CE in this area.