Understanding the pathogenic mechanisms and therapeutic effects in neurocysticercosis.

Despite being a leading cause of acquired seizures in endemic regions, the pathological mechanisms of neurocysticercosis are still poorly understood. This study aims to investigate the impact of anthelmintic treatment on neuropathological features in a rat model of neurocysticercosis. Rats were intracranially infected with Taenia solium oncospheres and treated with albendazole + praziquantel (ABZ), oxfendazole + praziquantel (OXF), or untreated placebo (UT) for 7 days. Following the last dose of treatment, brain tissues were evaluated at 24 h and 2 months. We performed neuropathological assessment for cyst damage, perilesional brain inflammation, presence of axonal spheroids, and spongy changes. Both treatments showed comparable efficacy in cyst damage and inflammation. The presence of spongy change correlated with spheroids counts and were not affected by anthelmintic treatment. Compared to white matter, gray matter showed greater spongy change (91.7% vs. 21.4%, p < 0.0001), higher spheroids count (45.2 vs. 0.2, p = 0.0001), and increased inflammation (72.0% vs. 21.4%, p = 0.003). In this rat model, anthelmintic treatment destroyed brain parasitic cysts at the cost of local inflammation similar to what is described in human neurocysticercosis. Axonal spheroids and spongy changes as markers of damage were topographically correlated, and not affected by anthelmintic treatment.

Impaired spatial working memory and reduced hippocampal neuronal density in a rat model of neurocysticercosis.

Neurocysticercosis (NCC) is the most common parasitic disease affecting the nervous system and is a leading cause of acquired epilepsy worldwide, as well as cognitive impairment, especially affecting memory. The aim of this study was to evaluate the effect of NCC on spatial working memory and its correlation with hippocampal neuronal density, in a rat model of NCC. This experimental study was conducted on female (n = 60) and male (n = 73) Holtzman rats. NCC was induced by intracranial inoculation of T. solium oncospheres in 14 day-old-rats. Spatial working memory was assessed using the T-maze test at 3, 6, 9, and 12 months post-inoculation, and sensorimotor evaluation was performed at 12 months post-inoculation. Hippocampal neuronal density was evaluated by immunostaining of NeuN-positive cells of the CA1 region. Of the rats inoculated with T. solium oncospheres, 87.2% (82/94) developed NCC. The study showed a significant decline in spatial working memory over a 1-year follow-up period in rats experimentally infected with NCC. Males showed an early decline that started at 3 months, while females demonstrated it at 9 months. Additionally, a decrease in neuronal density was observed in the hippocampus of NCC-infected rats, with a more significant reduction in rats with cysts in the hippocampus than in rats with cysts in other brain areas and control rats. This rat model of NCC provides valuable support for the relationship between neurocysticercosis and spatial working memory deficits. Further investigations are required to determine the mechanisms involved in cognitive impairment and establish the basis for future treatments.

The Amazonian Tropical Bites Research Initiative, a hope for resolving zoonotic neglected tropical diseases in the One Health era.

BACKGROUND: Neglected tropical diseases (NTDs) disproportionately affect populations living in resource-limited settings. In the Amazon basin, substantial numbers of NTDs are zoonotic, transmitted by vertebrate (dogs, bats, snakes) and invertebrate species (sand flies and triatomine insects). However, no dedicated consortia exist to find commonalities in the risk factors for or mitigations against bite-associated NTDs such as rabies, snake envenoming, Chagas disease and leishmaniasis in the region. The rapid expansion of COVID-19 has further reduced resources for NTDs, exacerbated health inequality and reiterated the need to raise awareness of NTDs related to bites. METHODS: The nine countries that make up the Amazon basin have been considered (Bolivia, Brazil, Colombia, Ecuador, French Guiana, Guyana, Peru, Surinam and Venezuela) in the formation of a new network. RESULTS: The Amazonian Tropical Bites Research Initiative (ATBRI) has been created, with the aim of creating transdisciplinary solutions to the problem of animal bites leading to disease in Amazonian communities. The ATBRI seeks to unify the currently disjointed approach to the control of bite-related neglected zoonoses across Latin America. CONCLUSIONS: The coordination of different sectors and inclusion of all stakeholders will advance this field and generate evidence for policy-making, promoting governance and linkage across a One Health arena.

Antibody Banding Patterns on the Enzyme-Linked Immunoelectrotransfer Blot (EITB) Assay Clearly Discriminate Viable Cysticercosis in Naturally Infected Pigs.

Enzyme-linked immunoelectrotransfer blot (EITB) detects antibodies against seven Taenia solium larvae antigens in three protein families (GP50, T24/42, and 8-kDa) with different structures and functions. EITB banding patterns against these antigens in pigs provide information about the course of infection and may discriminate viable cysticercosis. We analyzed the banding patterns and infection outcomes (presence of viable cysts, degenerated cysts, and any cysts) of 512 rural pigs. Banding patterns were grouped into homogenous classes using latent class analysis, and relationships with infection outcomes were assessed. Four classes were identified: 1 (n = 308, EITB-negative or positive for the GP50 family), 2 (n = 127, positive for GP50 (GP50 family), GP42-39 and GP24 (T24/42 family), but negative for 8-kDa antigens), 3 (n = 22, positive for GP50 and T24/42 antigens (GP42-39 and GP24), as well as to 8-kDa bands GP13, GP14, and GP18, but negative for GP21), and 4 (n = 55, positive for GP50 and T24/42 antigens, as well as to 8-kDa antigens GP21 and GP18 in combination). Pigs in classes 3 and 4 were more likely to have viable cysts (72.6% and 96.4%, respectively) than pigs in classes 1 and 2 (0.7% and 27.6%, respectively; p < 0.001). The number of infections with any cysts was higher in classes 3 and 4 (77.3% and 98.2%, respectively) and lower in classes 2 and 1 (34.7% and 4.9%, respectively; p < 0.001). Pigs with viable cysts represented >90% of pigs with any cysts in classes 3 and 4 (94.1% and 98.2%, respectively), while degenerated cysts were frequent among pigs with any cysts in classes 1, 3, and 2 (86.7%, 47.1%, and 43.2%, respectively; p < 0.001). EITB banding patterns strongly correlate with cysticercosis infection status in rural pigs, with classes 3 and 4 being more predictive of viable infections.

Genetic subtyping and phylogenetic analysis of HA and NA from avian influenza virus in wild birds from Peru reveals unique features among circulating strains in America.

Avian influenza virus (AIV) represents a major concern with productive implications in poultry systems but it is also a zoonotic agent that possesses an intrinsic pandemic risk. AIV is an enveloped, negative-sense and single-stranded RNA virus with a segmented genome. The eight genomic segments, comprising the whole genome, encode for eleven proteins. Within these proteins, Hemagglutinin (HA) and Neuraminidase (NA) are the most relevant for studies of evolution and pathogenesis considering their role in viral replication, and have also been used for classification purposes. Migratory birds are the main hosts and play a pivotal role in viral evolution and dissemination due to their migratory routes that comprise large regions worldwide. Altogether, viral and reservoir factors contribute to the emergence of avian influenza viruses with novel features and pathogenic potentials. The study aimed to conduct surveillance of AIVs in wild birds from Peru. A multi-site screening of feces of migratory birds was performed to isolate viruses and to characterize the whole genome sequences, especially the genes coding for HA and NA proteins. Four-hundred-twenty-one (421) fecal samples, collected between March 2019 and March 2020 in Lima, were obtained from 21 species of wild birds. From these, we isolated five AIV from whimbrel, kelp gull, Franklin's gulls and Mallard, which were of low pathogenicity, including four subtypes as H6N8, H13N6, H6N2 and H2N6. Genetic analysis of HA and NA genes revealed novel features in these viruses and phylogenetic analysis exhibited a close relationship with those identified in North America (US and Canada). Furthermore, H2N6 isolate presented a NA sequence with higher genetic relationship to Chilean isolates. These results highlight that the geographical factor is of major relevance in the evolution of AIV, suggesting that AIV circulating in Peru might represent a new site for the emergence of reassortant AIVs.

Echinococcus granulosus sensu stricto and E. canadensis are distributed in livestock of highly endemic area in the Peruvian highlands.

The prevalence of cystic echinococcosis is high in many livestock areas of Peru, where intermediate hosts such as sheep, cattle, and South American camelids can be infected. Several species of E. granulosus have been described in relation to its genetic diversity and distribution. The aim of this study was to determine the species of E. granulosus sensu lato (s.l.) metacestodes collected from sheep, cattle, swine and camelids at different localities in the department of Puno, in the southern highlands of Peru. One hundred and fifty-two echinococcal cysts were collected from 10 different locations. E. granulosus s.l. species were determined by amplification of the Internal transcribed spacer 1 of the ribosomal DNA using a Nested PCR-RFLP technique. The cytochrome C oxidase 1 gene (450 bp) was also amplified and sequenced in samples with different RFLP patterns. Cysts samples were collected from sheep (39.5%), cattle (32.9%), pigs (15.8%) and alpacas/llamas (11.8%). E. granulosus sensu stricto (G1 genotype) was mainly identified in all animal hosts, while, the E. canadensis (G7) was only identified in cysts from pigs and alpacas. This is the first report of E. granulosus sensu stricto and E. canadensis in llamas and alpacas, respectively. Knowledge of species and molecular epidemiology of E. granulosus s.l. in endemic areas in Peru may help to evaluate preventive programs, understand disease transmission, as well as improve vaccine and chemotherapy effectiveness.

Geographically Targeted Interventions versus Mass Drug Administration to Control Taenia solium Cysticercosis, Peru.

Optimal control strategies for Taenia solium taeniasis and cysticercosis have not been determined. We conducted a 2-year cluster randomized trial in Peru by assigning 23 villages to 1 of 3 geographically targeted intervention approaches. For ring screening (RS), participants living near pigs with cysticercosis were screened for taeniasis; identified cases were treated with niclosamide. In ring treatment (RT), participants living near pigs with cysticercosis received presumptive treatment with niclosamide. In mass treatment (MT), participants received niclosamide treatment every 6 months regardless of location. In each approach, half the villages received targeted or mass oxfendazole for pigs (6 total study arms). We noted significant reductions in seroincidence among pigs in all approaches (67.1% decrease in RS, 69.3% in RT, 64.7% in MT; p<0.001), despite a smaller proportion of population treated by targeted approaches (RS 1.4%, RT 19.3%, MT 88.5%). Our findings suggest multiple approaches can achieve rapid control of T. solium transmission.

First inter-laboratory comparison of Echinococcus granulosus sensu lato diagnosis in Latin America

[ABSTRACT]. Objective. To compare the performance of polymerase chain reaction (PCR) and enzyme-linked immunosorbent assay (ELISA) tests for diagnosing Echinococcus granulosus in dog feces among national reference laboratories in Argentina, Chile, Peru, and Uruguay. Methods. National laboratories affiliated with the Ministry of Health/Agriculture of each country exchanged panels of 10 positive/negative samples obtained from their regular national surveillance programs in November 2015 – November 2016. All laboratories applied PCR; two also applied ELISA techniques. Sensitivity and specificity were determined for each laboratory and concordance of results among the laboratories was evaluated by Cohen Kappa coefficient. Results. Poor concordance (3 of 10 paired comparisons had values of Kappa > 0.4), low sensitivity and specificity across all laboratories, and poor performance of both techniques in detecting E. granulosus in canine feces was demonstrated in this study. An ex-post comparison of the laboratories’ test protocols showed substantial heterogeneity that could partially explain poor concordance of results. Conclusion. The results underscore the heterogeneity of canine echinococcosis diagnosis across the region and indicate possible sources of variability. Efforts to standardize canine echinococcosis testing must be included in the plan of action for the Regional Initiative for the Control of Cystic Echinococcosis. Future comparisons with fecal samples of known parasite load are needed.

[RESUMEN]. Objetivo. Comparar el rendimiento de los ensayos de la reacción en cadena de la polimerasa y el enzimoinmunoanálisis de adsorción en fase sólida (o ELISA, por su sigla en inglés) para diagnosticar Echinococcus granulosus en heces caninas en los laboratorios de referencia nacionales de Argentina, Chile, Perú y Uruguay. Métodos. Los laboratorios nacionales, afiliados a los ministerios de salud y agricultura y ganadería de cada país, intercambiaron paneles de diez muestras positivas y negativas obtenidas de sus respectivos programas nacionales de vigilancia desde el mes de noviembre del año 2015 hasta el mismo mes del año siguiente. Todos los laboratorios emplearon la reacción en cadena de la polimerasa y dos emplearon también técnicas de ensayo inmunoenzimático (ELISA). Se determinó la sensibilidad y la especificidad de cada laboratorio y se evaluó la concordancia entre los resultados de los laboratorios mediante el coeficiente kappa de Cohen. Resultados. Este estudio descubrió una escasa concordancia (3 de 10 comparaciones de pares obtuvieron valores de kappa > 0,4), una sensibilidad y especificidad bajas en todos los laboratorios y un rendimiento deficiente de ambas técnicas de diagnóstico de Echinococcus granulosus en heces caninas. La comparación ex post de los protocolos de ensayo de los laboratorios mostró una heterogeneidad sustancial que podría explicar parcialmente la escasa concordancia de los resultados. Conclusiones. Los resultados subrayan la heterogeneidad del diagnóstico de equinococosis canina en toda la región e indican posibles fuentes de esta variabilidad. Deben incluirse medidas para estandarizar la prueba de equinococosis canina en el plan de acción de la Iniciativa Sudamericana para el Control de la Equinococosis Quística. En el futuro serán necesarias comparaciones adicionales con muestras fecales con una carga de parásitos conocida.

[RESUMO]. Objetivo. Comparar o desempenho dos métodos de reação em cadeia da polimerase (PCR) e ensaio imunoenzimático (ELISA) no diagnóstico de infecção pelo Echinococcus granulosus em fezes de cães entre laboratórios de referência nacional na Argentina, Chile, Peru e Uruguai. Métodos. Laboratórios nacionais conveniados ao Ministério da Saúde/Agricultura de cada país participante intercambiaram grupos de 10 amostras positivas/negativas coletadas rotineiramente pelos programas nacionais de vigilância no período de novembro de 2015 a novembro de 2016. Todos os laboratórios empregaram o método de PCR e dois empregaram também o método de ELISA. A sensibilidade e a especificidade dos métodos foram determinadas em cada laboratório, e a concordância dos resultados entre os laboratórios participantes foi avaliada com o coeficiente kappa de Cohen. Resultados. Observou-se fraca concordância (3 de 10 comparações pareadas com kappa >0,4), baixa sensibilidade e especificidade e fraco desempenho de ambos os métodos na identificação do E. granulosus em amostras fecais de cães nos laboratórios participantes do estudo. Uma comparação retroativa revelou considerável heterogeneidade dos protocolos de análise laboratorial, o que poderia em parte explicar a fraca concordância entre os resultados. Conclusões. Os resultados deste estudo apontam para a falta de uniformidade no diagnóstico de equinococose canina em toda a Região e indicam possíveis causas para variabilidade. A padronização da análise laboratorial da equinococose canina deve constar do plano de ação para a Iniciativa Regional para Controle da Hidatidose. Outras comparações de amostras fecais de parasitas conhecidos devem ser realizadas.

Economic Effect of Confiscation of Cattle Viscera Infected with Cystic Echinococcosis, Huancayo Province, Peru.

We report cystic echinococcosis (CE) prevalence in Huancayo Province, Peru, and the associated economic effect of bovine organ condemnation. CE prevalence during the 16-month study period was 42.8% and caused $14,595 in economic losses. CE threatens food security in the region by reducing farmers' income and viscera supply in markets.

Control of cystic echinococcosis: Background and prospects.

Cystic echinococcosis (CE), caused by Echinococcus granulosus, is a chronic and debilitating zoonotic larval cestode infection in humans, which is principally transmitted between dogs and domestic livestock, particularly sheep. Human CE occurs in almost all pastoral communities and rangeland areas of the underdeveloped and developed world. Control programmes against CE have been implemented in several endemic countries to reduce or eliminate the disease. New Zealand and Tasmania are examples of some of the first programmes to be undertaken (in insular territories) and which were very successful in the elimination of CE. The advent and proven effectiveness of praziquantel, plus the experience of insular models, produced high expectations for rapid advances in a second generation of control programmes undertaken in continental areas (Argentina, Uruguay and Chile). Nevertheless, only moderate gains in CE control have been made and the impact on prevalence among humans has been slight. A major impediment to the adoption of procedures that were successful in New Zealand and Tasmania has been the requirement to administer praziquantel to dogs in rural areas eight times per year over numerous years. In addition, there have been clear technological improvements made in the diagnosis of canine echinococcosis for surveillance, the genetic characterization of parasite strains and in vaccination against CE infection in livestock. In order to establish new paradigms and appropriate combinations of control strategies, we have carried out a review and discussion of the available control tools and control models. Control strategies must be suitable and sustainable to benefit the Echinococcosis-endemic areas primarily, which at the same time are the poorest regions of the world.

Blood-brain barrier disruption and angiogenesis in a rat model for neurocysticercosis.

Neurocysticercosis (NCC) is a helminth infection affecting the central nervous system caused by the larval stage (cysticercus) of Taenia solium. Since vascular alteration and blood-brain barrier (BBB) disruption contribute to NCC pathology, it is postulated that angiogenesis could contribute to the pathology of this disease. This study used a rat model for NCC and evaluated the expression of two angiogenic factors called vascular endothelial growth factor (VEGF-A) and fibroblast growth factor (FGF2). Also, two markers for BBB disruption, the endothelial barrier antigen and immunoglobulin G, were evaluated using immunohistochemical and immunofluorescence techniques. Brain vasculature changes, BBB disruption, and overexpression of angiogenesis markers surrounding viable cysts were observed. Both VEGF-A and FGF2 were overexpressed in the tissue surrounding the cysticerci, and VEGF-A was overexpressed in astrocytes. Vessels showed decreased immunoreactivity to endothelial barrier antigen marker and an extensive staining for IgG was found in the tissues surrounding the cysts. Additionally, an endothelial cell tube formation assay using human umbilical vein endothelial cells showed that excretory and secretory antigens of T. solium cysticerci induce the formation of these tubes. This in vitro model supports the hypothesis that angiogenesis in NCC might be caused by the parasite itself, as opposed to the host inflammatory responses alone. In conclusion, brain vasculature changes, BBB disruption, and overexpression of angiogenesis markers surrounding viable cysts were observed. This study also demonstrates that cysticerci excretory-secretory processes alone can stimulate angiogenesis.

Development and Validation of a Copro-Enzyme-Linked Immunosorbent Assay Sandwich for Detection of Echinococcus granulosus-Soluble Membrane Antigens in Dogs.

Cystic echinococcosis (CE) is a parasitic zoonosis caused by the larval stage of the tapeworm Echinococcus granulosus. Detection of the adult stage in the canine definitive host is essential for estimating infection rates, surveillance and monitoring of CE control programs. This study sought to develop and validate a coproantigen sandwich enzyme-linked immunosorbent assay (copro-ELISA), based on antibodies against E. granulosus-soluble membrane antigens (EGMA), that is capable of distinguishing infected and noninfected dogs. Anti-E. granulosus polyclonal immunoglobulin G antibodies were obtained from rabbit antiserum against EGMA. Optimization of the test was performed with 51 positive and 56 negative stool samples of canine echinococcosis. Specificity, sensitivity, cross-reactivity, intra- and inter-assay precision, and over time detection were evaluated. According to the receiver operating characteristic analysis, the diagnostic sensitivity and specificity were 96.1% (CI: 85.9-99.6) and 98.2% (CI: 89.5-100), respectively. Negative and positive predictive values were 96.5% (CI: 91.7-100) and 98% (CI: 94.1-100), respectively. No cross-reactivity with Taenia hydatigena, Dipylidium caninum, or Toxocara canis was observed. Intra- and inter-assay repeatability showed values of less than 15% of the variation coefficient. The over time detection was from 20 to 27 days postinfection with E. granulosus. The copro-ELISA based on EGMA detection offers a simplified in-house development of diagnostic testing. This assay showed high specificity and sensitivity and had no cross-reactivity with other parasites. Further studies and development of this test in a kit format may be useful for the detection of active infection in dogs living in CE endemic regions.

Axonal swellings and spheroids: a new insight into the pathology of neurocysticercosis.

Neurocysticercosis is a parasitic brain disease caused by the larval form (Cysticercus cellulosae) of Taenia solium and is the leading cause of preventable epilepsy worldwide. However, the pathophysiology and relation to the wide range of clinical features remains poorly understood. Axonal swelling is emerging as an important early pathological finding in multiple neurodegenerative diseases and as a cause of brain injury, but has not been well described in neurocysticercosis. Histological analysis was performed on human, rat and porcine NCC brain specimens to identify axonal pathology. Rat infection was successfully carried out via two routes of inoculation: direct intracranial injection and oral feeding. Extensive axonal swellings, in the form of spheroids, were observed in both humans and rats and to a lesser extent in pigs with NCC. Spheroids demonstrated increased immunoreactivity to amyloid precursor protein and neurofilament indicating probable impairment of axonal transport. These novel findings demonstrate that spheroids are present in NCC which is conserved across species. Not only is this an important contribution toward understanding the pathogenesis of NCC, but it also provides a model to analyze the association of spheroids with specific clinical features and to investigate the reversibility of spheroid formation with antihelminthic treatment.

First inter-laboratory comparison of Echinococcus granulosus sensu lato diagnosis in Latin America.

OBJECTIVE: To compare the performance of polymerase chain reaction (PCR) and enzyme-linked immunosorbent assay (ELISA) tests for diagnosing Echinococcus granulosus in dog feces among national reference laboratories in Argentina, Chile, Peru, and Uruguay. METHODS: National laboratories affiliated with the Ministry of Health/Agriculture of each country exchanged panels of 10 positive/negative samples obtained from their regular national surveillance programs in November 2015 - November 2016. All laboratories applied PCR; two also applied ELISA techniques. Sensitivity and specificity were determined for each laboratory and concordance of results among the laboratories was evaluated by Cohen Kappa coefficient. RESULTS: Poor concordance (3 of 10 paired comparisons had values of Kappa > 0.4), low sensitivity and specificity across all laboratories, and poor performance of both techniques in detecting E. granulosus in canine feces was demonstrated in this study. An ex-post comparison of the laboratories' test protocols showed substantial heterogeneity that could partially explain poor concordance of results. CONCLUSION: The results underscore the heterogeneity of canine echinococcosis diagnosis across the region and indicate possible sources of variability. Efforts to standardize canine echinococcosis testing must be included in the plan of action for the Regional Initiative for the Control of Cystic Echinococcosis. Future comparisons with fecal samples of known parasite load are needed.

Carotid Taenia solium Oncosphere Infection: A Novel Porcine Neurocysticercosis Model.

Neurocysticercosis (NCC), the infection of the human central nervous system (CNS) with larval cysts of Taenia solium causes widespread neurological morbidity. Animal models are crucial for studying the pathophysiology and treatment of NCC. Some drawbacks of current NCC models include differences in the pathogenesis of the model and wild-type parasite, low rates of infection efficiency and lack of reproducibility. We describe a novel porcine model that recreates infection in the CNS with high efficiency. Activated oncospheres, either in a high (45,000-50,000) or low (10,000) dose were inoculated in the common carotid artery of 12 pigs by ultrasound-guided catheterization. Following oncosphere injection, either a high (30 mL) or low (1-3 mL) volume of saline flush was also administered. Cyst burden in the CNS was evaluated independently according to oncosphere dose and flush volume. Neurocysticercosis was achieved in 8/12 (66.7%) pigs. Cyst burden in the CNS of pigs was higher in the high versus the low oncosphere dose category (median: 4.5; interquartile ranges [IQR]: 1-8 and median: 1; IQR: 0-4, respectively) and in the high versus the low flush volume category (median 5.5; IQR: 1-8 and median: 1; IQR: 0-2, respectively), although not statistically different. All cysts in the CNS were viable, whereas both viable and degenerated cysts were found in the musculature. Carotid injection of activated oncospheres in pigs is effective in reproducing NCC. Oncosphere entry into the CNS by way of vasculature mimics wild-type infection, and provides a useful alternative for future investigations on the pathogenesis and antiparasitic treatment of NCC.

Molecular Characterization of Tandem Repeat Protein 36 Gene of Ehrlichia canis Detected in Naturally Infected Dogs from Peru.

Ehrlichia spp. are emerging infectious pathogens, especially in the Americas. Although Ehrlichia canis is primarily a parasite of dogs, polymerase chain reaction-confirmed human infections have been reported from Mexico, Venezuela, and Costa Rica. This study reports the presence of E. canis DNA in 13.7% of 205 dogs from urban areas in Peru and of those, five were analyzed for phylogenetic variation using the Tandem Repeat Protein 36 (TRP36) gene. The use of the TRP36 gene for such analysis was validated against 16S rRNA and heat shock protein genes using Shannon's entropy bioinformatic approach. When compared with other E. canis strains previously reported, three unique and novel E. canis strains were detected. In addition, the TRP36 amino acid tandem repeat sequences of the Peruvian strains share close similarity to an E. canis strain detected from four human blood bank samples in Costa Rica. This study reports for the first time domestic dogs infected with E. canis strains closely related to a zoonotic strain, which may be of public health concern as dogs can be chronically infected with this pathogen.

Hematology and serum biochemistry of free-ranging and captive Sechuran foxes (Lycalopex sechurae).

BACKGROUND: Hematologic and serum biochemical reference values obtained from captive or free-ranging wildlife populations may not be comparable as there can be significant variations due to preanalytic and analytic differences, including methods of capture and restraint, overall management in captivity including diet and composition of animal groups, and analytic methods being used. Hematology and serum biochemistry have never been studied in captive or free-ranging populations of Sechuran foxes (Lycalopex sechurae). OBJECTIVES: The purposes of the study were to determine hematologic and serum biochemical RI in Sechuran foxes and to explore differences in these variables related to sex and overall life circumstances. METHODS: Blood samples were obtained from 15 free-ranging and 15 captive Sechuran foxes. Hematology variables were assessed by blood smear examination and automated analyzer methodology. Serum biochemical analysis was performed by automated analyzer methodology. Descriptive statistics were calculated for each variable. Data obtained from free-ranging and captive groups were statistically compared and RIs were calculated. RESULTS: Captive Sechuran foxes had significantly (P < .05) higher MCH, MCHC, and eosinophil counts and significantly lower band neutrophil counts than free-ranging foxes. Free-ranging Sechuran foxes had significantly (P < .05) higher serum lipase and globulins and significantly lower albumin, total bilirubin, and indirect bilirubin than captive foxes. CONCLUSIONS: These findings suggest that there are hematologic and serum biochemical differences between captive and free-ranging Sechuran fox populations. Hence, such differences should be considered when using these variables to assess the health status of this species.

Genetic variability of Taenia solium cysticerci recovered from experimentally infected pigs and from naturally infected pigs using microsatellite markers.

The adult Taenia solium, the pork tapeworm, usually lives as a single worm in the small intestine of humans, its only known definitive host. Mechanisms of genetic variation in T. solium are poorly understood. Using three microsatellite markers previously reported [1], this study explored the genetic variability of T. solium from cysts recovered from experimentally infected pigs. It then explored the genetic epidemiology and transmission in naturally infected pigs and adult tapeworms recovered from human carriers from an endemic rural community in Peru. In an initial study on experimental infection, two groups of three piglets were each infected with proglottids from one of two genetically different tapeworms for each of the microsatellites. After 7 weeks, pigs were slaughtered and necropsy performed. Thirty-six (92.3%) out of 39 cysts originated from one tapeworm, and 27 (100%) out of 27 cysts from the other had exactly the same genotype as the parental tapeworm. This suggests that the microsatellite markers may be a useful tool for studying the transmission of T. solium. In the second study, we analyzed the genetic variation of T. solium in cysts recovered from eight naturally infected pigs, and from adult tapeworms recovered from four human carriers; they showed genetic variability. Four pigs had cysts with only one genotype, and four pigs had cysts with two different genotypes, suggesting that multiple infections of genetically distinct parental tapeworms are possible. Six pigs harbored cysts with a genotype corresponding to one of the identified tapeworms from the human carriers. In the dendrogram, cysts appeared to cluster within the corresponding pigs as well as with the geographical origin, but this association was not statistically significant. We conclude that genotyping of microsatellite size polymorphisms is a potentially important tool to trace the spread of infection and pinpoint sources of infection as pigs spread cysts with a shared parental genotype.

Cystic echinococcosis in South America: a call for action.

Cystic echinococcosis (CE) or hydatidosis, a parasitic zoonosis caused by a cestode of the family Taeniidae, species Echinococcus granulosus, is endemic in Argentina, Chile, Peru, Uruguay, and southern Brazil. This report presents CE figures for these five countries in 2009 - 2014 and proposes indicators to measure national control programs. Nearly 5 000 new CE cases were diagnosed annually in the five countries during the study period. The average case fatality rate was 2.9%, which suggests that CE led to approximately 880 deaths in these countries during the 6-year period. CE cases that required secondary or tertiary health care had average hospital stays of 10.6 days, causing a significant burden to health systems. The proportion of new cases (15%) in children less than 15 years of age suggests ongoing transmission. Despite figures showing that CE is not under control in South America, the long-standing implementation of national and local control programs in three of the five countries has achieved reductions in some of the indicators. The Regional Initiative for the Control of CE, which includes the five countries and provides a framework for networking and collaboration, must intensify its efforts.

Cystic echinococcosis in South America: a call for action / La equinococosis quística en América del Sur: un llamamiento a la acción / Hidatidose na América do Sul: um chamado à ação

Cystic echinococcosis (CE) or hydatidosis, a parasitic zoonosis caused by a cestode of the family Taeniidae, species Echinococcus granulosus, is endemic in Argentina, Chile, Peru, Uruguay, and southern Brazil. This report presents CE figures for these five countries in 2009 – 2014 and proposes indicators to measure national control programs. Nearly 5 000 new CE cases were diagnosed annually in the five countries during the study period. The average case fatality rate was 2.9%, which suggests that CE led to approximately 880 deaths in these countries during the 6-year period. CE cases that required secondary or tertiary health care had average hospital stays of 10.6 days, causing a significant burden to health systems. The proportion of new cases (15%) in children less than 15 years of age suggests ongoing transmission. Despite figures showing that CE is not under control in South America, the long-standing implementation of national and local control programs in three of the five countries has achieved reductions in some of the indicators. The Regional Initiative for the Control of CE, which includes the five countries and provides a framework for networking and collaboration, must intensify its efforts.

La equinococosis quística o hidatidosis, zoonosis parasitaria causada por un cestodo de la especie Echinococcus granulosus, familia Taeniidae, es endémica en Argentina, Chile, Perú, Uruguay y el sur del Brasil. En este informe se presentan datos sobre la equinococosis quística registrados en estos cinco países entre los años 2009 y 2014, y se proponen indicadores para medir el desempeño de los programas nacionales de control. Durante el período de estudio, en los cinco países se diagnosticaron casi 5 000 casos nuevos por año. La tasa de letalidad promedio fue del 2,9 %, lo que indica que la equinococosis quística causó aproximadamente 880 defunciones en estos países en el período de 6 años estudiado. Los casos que debieron recibir atención de salud secundaria o terciaria tuvieron una estadía hospitalaria promedio de 10,6 días, lo que ha generado una carga significativa para los sistemas de salud. La proporción de casos nuevos de niños menores de 15 años (15 %) indica que la transmisión no se ha interrumpido. A pesar de que los datos muestran que la enfermedad no está controlada en América del Sur, tres de los cinco países disponen de programas nacionales y locales de control desde hace muchos años, los que han logrado reducir algunos de los indicadores. Es preciso que la Iniciativa Sudamericana para el Control de la Equinococosis Quística, que incluye a los cinco países y contribuye con un marco para la formación de redes y la colaboración, redoble sus esfuerzos para lograr el control de la enfermedad.

A equinococose cística ou hidatidose, zoonose parasitária causada por um céstodo da família Taeniidae e espécie Echinococcus granulosus, é endêmica na Argentina, Chile, Peru, Uruguai e no sul do Brasil. Neste artigo são apresentadas as estimativas da hidatidose nos cinco países de 2009 a 2014 e propostos indicadores para avaliar os programas nacionais de controle. Cerca de 5 mil casos novos de hidatidose foram diagnosticados por ano nos cinco países no período de estudo. A taxa de letalidade média foi de 2,9%, o que indica que esta doença causou aproximadamente 880 mortes nestes países no período de 6 anos. Nos casos de hidatidose que precisaram de atenção de saúde secundária ou terciária, a duração média da internação hospitalar foi de 10,6 dias, representando uma sobrecarga considerável aos sistemas de saúde. O percentual de novos casos (15%) em indivíduos menores de 15 anos de idade indica transmissão contínua. Apesar de as estimativas mostrarem que a hidatidose não está controlada na América do Sul, a execução permanente de programas municipais e nacionais de controle em três dos cinco países tem redundado na redução de alguns dos indicadores. A Iniciativa Regional para Controle da Hidatidose, que integra os cinco países em uma estrutura para trabalho em conjunto e colaboração, deve redobrar os seus esforços.