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The aim of the present study was to assess the resistance status of bovine gastrointestinal nematodes (GINs) against ivermectin (IVM) and fenbendazole (FBZ) in Ecuador. The study involved five cattle farms located in different topographic zones of the country. Anthelmintic efficacy was assessed by calculating the percentage of fecal egg counts reduction (FECR) after treatment. Additionally, DNA from pooled larval cultures was screened to ascertain benzimidazole resistance alleles. For animals treated with IVM, FECR percentages ranged from 0 to 68%, indicating the presence of highly resistant worms. The opposite was found for animals treated with FBZ, where FECR percentages were above 90% on all the farms tested. Pooled coprocultures revealed that Cooperia spp. were the predominant species pre and post-treatment although minor proportions of Haemonchus spp. and Ostertagia spp. were also identified. No mutations conferring resistance to benzimidazoles were identified in the beta-tubulin isotype 1 gene of the isolated Cooperia spp. worms, which is in line with the results of the FECR performed with FBZ. Overall, the present study highlights widespread resistance of bovine GINs to IVM but no to FBZ in Ecuador.

Some Lymnaeid snails are intermediate hosts of the liver fluke Fasciola hepatica, the causal agent of fasciolosis, a zoonotic parasitic disease. Human and livestock fasciolosis has been reported in a highland community located in the Chimborazo Province of the Ecuadorian Andes. However, no previous study has been carried out to identify which snail species act as intermediate host/s of F. hepatica. This study first aimed to identify the intermediate snail species and secondly to determine the prevalence of natural infection with F. hepatica in 230 lymnaeid snails sampled from irrigation and drainage canals in this area. The first objective entailed observations of shell morphology and internal organs as well as sequencing of the cytochrome oxidase subunit 1 (COI) gene. For the second objective, we used classic parasitological methods (observation of rediae and cercarial emission) and PCR amplification specie-specific to F. hepatica. COI haplotype networks were built to elucidate phylogeographic relationships between the snail populations from this highland community with other American and worldwide populations. We identified two lymnaeid Galba cousini and Galba schirazensis and found high infection rates of F. hepatica in G. cousini, but these differed according to the method used, with PCR showing a higher rate (61 ± 20%) compared to rediae observation (29 ± 17%). F. hepatica in G. schirazensis was identified only by DNA amplification. G. cousini populations were genetically structured by geographic distance whereas G. schirazensis populations showed very low genetic diversity. The higher abundance and infection rate of G. cousini compared to G. schirazensis suggests that the former is likely the specie responsible for F. hepatica transmission in this region.

Brucellosis is an important but neglected zoonosis that causes serious economic losses both in livestock and human populations. The aim of the present study was to estimate the true prevalence of brucellosis together with diagnostic sensitivity and specificity of three serological tests in humans of the northwestern part of Ecuador using a Bayesian approach adjusted for the dependencies among the multiple tests to avoid any misinterpretation. In addition, the causal agent responsible for human brucellosis was also identified. Using a total of 3,733 samples collected from humans in this area between 2006 and 2008, the prevalence of human brucellosis and the diagnostic test characteristics of the Rose Bengal fast agglutination test (RBT), Wright’s slow agglutination test with ethylenediaminetetraacetic acid disodium salt dehydrate (EDTA) (SAT-EDTA), and indirect ELISA (iELISA) were estimated using a Bayesian approach. The estimated true prevalence of human brucellosis was 1% (credibility interval: 0.4–1.6). The sensitivities of iELISA and RBT were higher than and similar (95.1% and 95.0%, respectively) to those of SAT-EDTA (60.8%). Even though all tests indicated a high specificity (> 99.0%), the specificity of SAT-EDTA was highest (99.9%). The circulating strain in this study area was identified to be Brucella abortus biotype 4 based on culture and microbiological characterization. The RBT and the iELISA are recommended for estimating the true prevalence of human brucellosis and/or for surveillance programs following their high sensitivities and specificities. The proposed strategy supports evidence-based medicine for clinicians and policy-makers to ensure appropriate preventive and control program of brucellosis worldwide.

Background: Q fever is an underreported zoonotic disease of cattle and men in most countries of the world. Very little information about the prevalence of Coxiella burnetii infection in animals and humans comes from South and Central America and systematic studies are lacking. Methods: A seroprevalence survey for Q fever amongst cattle, farm workers and students was conducted in Ecuador using a commercial ELISA kit. Results: Survey results showed an unexpectedly high prevalence of Coxiella burnetii antibodies in dairy cattle (43%) and in farm workers (34%). In addition, a clinical case in a human of acute Q fever in the convalescent stage was detected. Conclusion: We conclude that the disease is endemic in Ecuador but is overlooked by medical and laboratory personnel. Q fever should be considered a public health issue in Ecuador and further research into the clinical relevance of this infection is recommended.

International audience; Fasciolosis is a widely distributed disease in livestock in South America but knowledge about the epidemiology and the intermediate hosts is relatively scarce in Ecuador. For three months, lymnaeid snails were sampled (n = 1482) in Pichincha Province at two sites located in a highly endemic area. Snails were identified (based on morphology and ITS-2 sequences) and the infection status was established through microscopic dissection and a multiplex polymerase chain reaction (PCR)-based technique. Techniques based on morphology were not useful to accurately name the collected snail species. Comparison with available DNA sequences showed that a single snail species was collected, Galba schirazensis. Live rediae were observed in 1.75% (26/1482) and Fasciola sp. DNA was detected in 6% (89/1482) of collected snails. The COX-1 region permitted identification of the parasite as Fasciola hepatica. The relative sensitivity and specificity of the microscope study, compared to PCR results, were 25.84% and 99.78%, respectively. The mean size of the snails recorded positive for F. hepatica through crushing and microscopy was significantly higher than the mean size of negative snails, but there was no such difference in PCR-positive snails. The role of G. schirazensis as an intermediate host of F. hepatica in Ecuador is discussed and the hypothesis of an adaptation of the parasite to this invasive snail is proposed. For the first time, an epidemiological survey based on molecular biology-based techniques assessed the possible role of lymnaeid snails in the epidemiology of fasciolosis in Ecuador; La fasciolose est une maladie largement distribuée chez le bétail en Amérique du Sud, mais les connaissances sur l'épidémiologie et les hôtes intermédiaires sont relativement rares en Équateur. Pendant trois mois, les Lymnaeidae ont été échantillonnés (n = 1482) dans la province de Pichincha dans deux sites situés dans une zone fortement endémique. Les mollusques ont été identifiés (en fonction de la morphologie et des séquences ITS-2) et l'état de l'infection a été établi grâce à une dissection microscopique et une technique de PCR multiplex. Les techniques basées sur la morphologie n'ont pas été utiles pour identifier avec précision l'espèce de mollusque récoltée. Une comparaison avec les séquences d'ADN disponibles a montré qu'une seule espèce de mollusque a été récoltée, Galba schirazensis. Parmi les mollusques collectés, des rédies vivantes ont été observées chez 1.75 % (26/1482) et de l'ADN de Fasciola sp. été détecté dans 6 % (89/1482). La région COX-1 a permis d'identifier le parasite comme Fasciola hepatica. La sensibilité relative et la spécificité des études microscopiques, en comparaison avec les résultats de la PCR, étaient respectivement de 25.84 % et 99.78 %. La taille moyenne des mollusques considérés positifs pour F. hepatica par écrasement et microscopie était significativement plus élevée que la taille moyenne des mollusques négatifs, mais une telle différence n'a pas été trouvée chez les mollusques PCR-positifs. Le rôle de G. schirazensis en tant qu'hôte intermédiaire de F. hepatica en Équateur est discuté et l'hypothèse d'une adaptation du parasite à ce mollusque invasif est proposée. Pour la première fois, une enquête épidémiologique, basée sur des techniques de biologie moléculaire, a évalué le rôle possible des mollusques Lymnaeidae dans l'épidémiologie de la fasciolose en Équateur.

Background Human cysticercosis is a zoonotic disease causing severe health disorders and even death. While prevalence data become available worldwide, incidence rate and cumulative incidence figures are lacking, which limits the understanding of the Taenia solium epidemiology. Methodology/Principal findings A seroepidemiological cohort study was conducted in a south-Ecuadorian community to estimate the incidence rate of infection with and the incidence rate of exposure to T. solium based on antigen and antibody detections, respectively. The incidence rate of infection was 333.6 per 100,000 person-years (95% CI: [8.4–1,858] per 100,000 person-years) contrasting with a higher incidence rate of exposure 13,370 per 100,000 person-years (95% CI: [8,730–19,591] per 100,000 person-years). The proportion of infected individuals remained low and stable during the whole study year while more than 25% of the population showed at least one antibody seroconversion/seroreversion during the same time period. Conclusions/Significance Understanding the transmission of T. solium is essential to develop ad hoc cost-effective prevention and control programs. The estimates generated here may now be incorporated in epidemiological models to simulate the temporal transmission of the parasite and the effects of control interventions on its life cycle. These estimates are also of high importance to assess the disease burden since incidence data are needed to make regional and global projections of morbidity and mortality related to cysticercosis., Author Summary Human cysticercosis is a neglected zoonotic parasitic disease causing severe health disorders such as epilepsy and even death. Cysticercosis is related to poverty, inadequate hygiene conditions and traditional pig farming. The present study describes the dynamic nature of human Taenia solium larval infections in an Ecuadorian endemic community. In this study we report for the first time incidence rate and cumulative incidence figures of human T. solium larval infections in Latin America. The simultaneous use of antibody and antigen serological detections allowed estimating both parasite exposure and infection rates, respectively. While about 13% of the inhabitants were exposed to T. solium eggs, less than 1% of the population became yearly infected with the parasite. This contrast between exposure and infection may be linked to an effective resistance to the parasite acquired through long-term exposure of the population and differs from the African situation, where much higher levels of infection have been observed. These estimates are of high importance to understand the epidemiology of T. solium in order to develop ad hoc cost-effective prevention and control programs. They are also essential to assess the burden of T. solium cysticercosis since longitudinal data are needed to make regional and global projections of morbidity and mortality related to cysticercosis.

(Neuro)cysticercosis is an important zoonotic disease caused by infection with Taenia solium metacestode larvae. Existing immunodiagnostic techniques detect antibodies and circulating antigens (Ag) in serum and cerebrospinal fluid (CSF). Blood/CSF collection is an invasive procedure associated with blood-borne infections and is often not well accepted by communities. Detection of circulating Ag in urine has been suggested as an alternative, however this has been evaluated in clinical settings only. The aim of the present study was to evaluate the performance of a urine Ag-ELISA under field conditions. Paired serum and urine samples were obtained from participants in endemic areas of Ecuador (n=748) and Zambia (n=690) and were subjected to a monoclonal antibody-based Ag-ELISA. Calculation of positive and negative agreement indices (AI) showed better agreement in the negative direction both for Ecuadorian and Zambian samples (AI of 93.1 and 86.8, respectively). Using a Bayesian approach to determine the test characteristics, similar sensitivities were obtained for serum and urine Ag detection, whereas a decreased specificity was determined for the urine Ag-ELISA with a lower specificity (78.6%) for Zambian samples than for Ecuadorian samples (88.4%). This study indicates a higher specificity for the serum test under field conditions and promotes further research to improve the urine test.

We studied the prevalence of bovine tuberculosis (BTB) in Mejia canton, the major dairy cattle production area in northern Ecuador. Twenty dairy herds comprising 2,022 cattle were selected. In 2007, each animal was tested using the comparative intradermal tuberculin test (CITT). In 2008, a follow-up test was performed in the same herds. The true annual incidence was 1.70%, and the true prevalence was 7.41% and 7.13% in 2007 and 2008, respectively. The prevalence was 0.27% and 0.57% in medium-sized herds in 2007 and 2008, respectively, compared with 8.63% and 8.43% in large herds (P < 0.01). The number of skin testpositive cases also increased significantly with age (P = 0.03), contacts with other species of animals (P < 0.01), and introduction of new cattle (P = 0.04). Herd prevalence was 55% in 2007 and 65% in 2008. This study shows the lack of knowledge in cattle farmers about this zoonosis and the necessity for a national BTB control program in Ecuador.

Taenia solium is endemic in the Andean region of Ecuador. The recent rediscovery of Taenia saginata in humans urges to reconsider some assumptions in relation to the epidemiology of the taeniosis/cysticercosis complex in this country. Therefore, data were compiled on the infection of both tapeworms in man and animals in Pichincha and Imbabura provinces in the Andean region, north of Quito. On post mortem inspection 3 out of 806 (0.37%) carcasses had T. saginata metacestodes, however, 35 sera out of 869 (4.03%) showed circulating antigen in a monoclonal antibody-based sandwich ELISA (Ag-ELISA). Porcine cysticercosis was detected in 15 out of 2896 (0.52%) carcasses and 93 out of 1032 serum samples (9.01%) were positive in Ag-ELISA. In humans, 4.99% (215 out of 4306) cases of antigen positives were found, whereas coprological examination of 1935 stools resulted in 30 positive cases (1.55%). The limited number of adult tapeworms (29) that were collected does not allow firm conclusions on the proportion of each species, but in total 21 specimen were identified as T. saginata and 8 as T. solium . These data have been discussed in view of the epidemiology of human cysticercosis.