Hector H Garcia

Universidad Peruana Cayetano Heredia, Λίμα, Lima, Peru

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Publications (272)1628.68 Total impact

  • [Show abstract] [Hide abstract]
    ABSTRACT: Cystic echinococcosis (CE) is a zoonosis caused by the larval stage of the dog tapeworm Echinococcus granulosus. Liver and lungs are the most commonly affected organs whereas splenic infection is rarer and its primary involvement occurs in less than 2% of abdominal CE. We report a case of primary giant splenic hydatid cyst in a 75-year-old Peruvian woman that was laparoscopically removed without any complications, perioperative prophylactic chemotherapy with albendazole 400 mg twice a day 5 days before, and 7 days after the surgical procedure was administered, postoperative recovery was uneventful, and; at her 3-month follow-up the patient remains asymptomatic and an abdominal computed tomography scan demonstrated a cystic cavity of 15 cm diameter with no daughter vesicles, neither other abdominal organ involvement. This case is in line with the existing literature on laparoscopical treatment of splenic cystic hydatid disease, suggesting that laparoscopical treatment is a safe and effective approach for large splenic hydatid cysts to be preferred to open surgical techniques.
    The American journal of tropical medicine and hygiene 11/2015; DOI:10.4269/ajtmh.13-0505 · 2.70 Impact Factor
  • M.W. Lightowlers · H.H. Garcia · C G Gauci · M Donadeu · B Abela-Ridder ·
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    ABSTRACT: There is an increasing interest in reducing the incidence of human neurocysticercosis, caused by infection with the larval stage of Taenia solium. Several intervention trials are currently assessing various options for control of T. solium transmission. A critical aspect of these trials will be the evaluation of whether the interventions have been successful. However there is no consensus about the most appropriate or valuable methods that should be used. Here we undertake a critical assessment of the diagnostic tests which are currently available for human T. solium taeniasis and human and porcine cysticercosis, as well as their suitability for evaluation of intervention trial outcomes. Suggestions are made about which of the measures that are available for evaluation of T. solium interventions would be most suitable, and which methodologies are the most appropriate given currently available technologies. Suggestions are also made in relation to the most urgent research needs in order to address deficiencies in current diagnostic methods. This article is protected by copyright. All rights reserved.
    Parasite Immunology 11/2015; DOI:10.1111/pim.12291 · 2.14 Impact Factor
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    ABSTRACT: Background: The ability of Taenia solium to modulate the immune system likely contributes to their longevity in the human host. We tested the hypothesis that the nature of the immune response is related to the location of parasite and clinical manifestations of infection. Methodology: Peripheral blood mononuclear cells (PBMC) were obtained from untreated patients with neurocysticercosis (NCC), categorized as having parenchymal or subarachnoid infection by the presence of cysts exclusively within the parenchyma or in subarachnoid spaces of the brain, and from uninfected (control) individuals matched by age and gender to each patient. Using multiplex detection technology, sera from NCC patients and controls and cytokine production by PBMC after T. solium antigen (TsAg) stimulation were assayed for levels of inflammatory and regulatory cytokines. PBMC were phenotyped by flow cytometry ex vivo and following in vitro stimulation with TsAg. Principal findings: Sera from patients with parenchymal NCC demonstrated significantly higher Th1 (IFN-γ/IL-12) and Th2 (IL-4/IL-13) cytokine responses and trends towards higher levels of IL-1β/IL-8/IL-5 than those obtained from patients with subarachnoid NCC. Also higher in vitro antigen-driven TNF-β secretion was detected in PBMC supernatants from parenchymal than in subarachnoid NCC. In contrast, there was a significantly higher IL-10 response to TsAg stimulation in patients with subarachnoid NCC compared to parenchymal NCC. Although no differences in regulatory T cells (Tregs) frequencies were found ex vivo, there was a trend towards greater expansion of Tregs upon TsAg stimulation in subarachnoid than in parenchymal NCC when data were normalized for the corresponding controls. Conclusions/significance: T. solium infection of the subarachnoid space is associated with an enhanced regulatory immune response compared to infection in the parenchyma. The resulting anti-inflammatory milieu may represent a parasite strategy to maintain a permissive environment in the host or diminish inflammatory damage from the host immune response in the central nervous system.
    PLoS Neglected Tropical Diseases 10/2015; 9(10):e0004143. DOI:10.1371/journal.pntd.0004143 · 4.45 Impact Factor
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    ABSTRACT: Diagnosis of cystic echinococcosis (CE) is based on the identification of the cyst(s) by imaging, using immunodiagnostic tests mainly as complementary tools in clinical settings. Among the antigens used for immunodiagnosis, previous studies described a good performance of the recombinant antigen B8/1(rAgB) in an ELISA format; however in remote places of endemic areas, the implementation of an ELISA test is difficult, so a more simple, rapid and reliable method such as the immunochromatographic test (ICT) is required. In this study, using a set of 50 serum samples from CE surgically confirmed patients, we compared the performance of an ICT test and an ELISA test using the rAgB. The overall sensitivities of ICT and ELISA were not statistically different (78% vs. 72%, p=0.36). The overall agreement between both tests was moderate (k=0.41, p<0.01). Concordance between ICT and ELISA were substantial to almost perfect for patients with liver involvement (k=0.65, p<0.001), and patients with more than one hydatid cyst (k=0.82, p<0.001), respectively. Moreover, specificity analysis using a total of 88 serum samples from healthy individuals (n = 20) and patients (n = 68) with other parasitic infections revealed that ICT had a specificity of 89.8 %. ICT and ELISA test had similar performance for the detection of specific antibodies to E. granulosus and ICT had a high specificity, opening the possibility of using ICT as a screening tool in rural settings.
    Journal of clinical microbiology 10/2015; 53(12). DOI:10.1128/JCM.02157-15 · 3.99 Impact Factor
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    ABSTRACT: Taenia solium cysticercosis is a common parasitic infection of humans and pigs. We evaluated the posttreatment evolution of circulating parasite-specific antigen titers in 693 consecutive blood samples from 50 naturally infected cysticercotic pigs, which received different regimes of antiparasitic drugs (N = 39, 7 groups), prednisone (N = 5), or controls (N = 6). Samples were collected from baseline to week 10 after treatment, when pigs were euthanized and carefully dissected at necropsy. Antigen levels decreased proportionally to the efficacy of treatment and correlated with the remaining viable cysts at necropsy (Pearson's p = 0.67, P = 0.000). A decrease of 5 times in antigen levels (logarithmic scale) compared with baseline was found in 20/26 pigs free of cysts at necropsy, compared with 1/24 of those who had persisting viable cysts (odds ratio [OR] = 76.7, 95% confidence interval [CI] = 8.1-3308.6, P < 0.001). Antigen monitoring reflects the course of infection in the pig. If a similar correlation exists in infected humans, this assay may provide a minimally invasive and easy monitoring assay to assess disease evolution and efficacy of antiparasitic treatment in human neurocysticercosis.
    The American journal of tropical medicine and hygiene 09/2015; DOI:10.4269/ajtmh.15-0370 · 2.70 Impact Factor
  • Oscar H Del Brutto · Héctor H García ·
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    ABSTRACT: Human taeniasis as well as porcine and human cysticercosis - caused by the pork tapeworm Taenia solium - are ancient diseases. The fact that pigs were considered impure in the ancient Greece and that the Koran prohibited the consumption of pork, were likely related to the knowledge that cysticercosis may affect swine. Evidence suggests that human cysticercosis was also present in the ancient Egypt and Rome. During the Renaissance, the causative agent was properly identified and human cases were recognized. Confirmation that both taeniasis and cysticercosis were caused by the same parasite was provided during the 19th Century by German pathologists. During the 20th Century, bouts of human cysticercosis in non-endemic regions left us valuable lessons on the mechanisms of disease acquisition and spread. These included a large series of neurocysticercosis cases in the United Kingdom that occurred after the return of troops stationed in India (which demonstrated that symptoms may occur years after infection), the epidemic of cysticercosis-related epilepsy in the Ekari people of Papua New Guinea occurring after the gift of pigs with cysticercosis received from Indonesia (demonstrating the fast establishment of endemic transmission and the impact of cysticercosis in epilepsy frequency), and the occurrence of neurocysticercosis among members of an Orthodox Jewish community of New York City, related to Latin American Taenia carriers working in their houses (highlighting the fact that cysticercosis transmission do not require the presence of infected pigs). These lessons of history have significantly contributed to our current knowledge on this disease. Copyright © 2015 Elsevier B.V. All rights reserved.
    Journal of the neurological sciences 08/2015; DOI:10.1016/j.jns.2015.08.011 · 2.47 Impact Factor
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    ABSTRACT: Neurocysticercosis is caused by Taenia solium infecting the central nervous system and is the leading cause of acquired epilepsy and convulsive conditions worldwide. Research into the pathophysiology of the disease and appropriate treatment is hindered by lack of cost-effective and physiologically similar animal models. We generated a novel rat neurocysticercosis model using intracranial infection with activated T. solium oncospheres. Holtzman rats were infected in two separate groups: the first group was inoculated extraparenchymally and the second intraparenchymally, with different doses of activated oncospheres. The groups were evaluated at three different ages. Histologic examination of the tissue surrounding T. solium cysticerci was performed. Results indicate that generally infected rats developed cysticerci in the brain tissue after 4 months, and the cysticerci were observed in the parenchymal, ventricle, or submeningeal brain tissue. The route of infection did not have a statistically significant effect on the proportion of rats that developed cysticerci, and there was no dependence on infection dose. However, rat age was crucial to the success of the infection. Epilepsy was observed in 9% of rats with neurocysticercosis. In histologic examination, a layer of collagen tissue, inflammatory infiltrate cells, perivascular infiltrate, angiogenesis, spongy change, and mass effect were observed in the tissue surrounding the cysts. This study presents a suitable animal model for the study of human neurocysticercosis. Copyright © 2015 American Society for Investigative Pathology. Published by Elsevier Inc. All rights reserved.
    American Journal Of Pathology 08/2015; 185(8):2259-68. DOI:10.1016/j.ajpath.2015.04.015 · 4.59 Impact Factor
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    ABSTRACT: The efficacy of oxfendazole (OFZ) on Taenia hydatigena metacestodes, also called Cysticercus tenuicollis (C. tenuicollis), was studied in 648 raising pigs. This study was performed in Tumbes Department in Peru, an endemic area for cysticercosis. Pigs were randomized in two groups; untreated group (n = 142) did not receive any treatment and treated group (n = 506) received OFZ treatment at a single dose of 30 mg/kg body weight. Six months after treatment, the pigs were necropsied. The prevalence of infection by C. tenuicollis among the pigs was 27.5% (39/142) and 2.0% (10/506) in untreated and treated groups, respectively. Untreated group was infested only with viable cysts, whereas treated group had no viable cysts. All the cysts found in treated group presented degeneration, with a thick membrane, and they contained milky fluid and fibrous tissue. A single dose of OFZ was effective against C. tenuicollis, thus providing an alternative drug for controlling this parasite in pigs.
    Asian Pacific Journal of Tropical Biomedicine 08/2015; DOI:10.1016/j.apjtb.2015.03.013

  • Epilepsia 06/2015; 56(6):975-6. DOI:10.1111/epi.12986 · 4.57 Impact Factor

  • The Lancet Infectious Diseases 03/2015; 15(3). DOI:10.1016/S1473-3099(15)70047-2 · 22.43 Impact Factor
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    ABSTRACT: Cysticidal treatment of neurocysticercosis, an infection of humans and pig brains with Taenia solium, results in an early inflammatory response directed to cysts causing seizures and focal neurological manifestations. Treatment-induced pericystic inflammation and its association with blood brain barrier (BBB) dysfunction, as determined by Evans blue (EB) extravasation, was studied in infected untreated and anthelmintic-treated pigs. We compared the magnitude and extent of the pericystic inflammation, presence of EB-stained capsules, the level of damage to the parasite, expression of genes for proinflammatory and regulatory cytokines, chemokines, and tissue remodeling by quantitative PCR assays between treated and untreated infected pigs and between EB-stained (blue) and non stained (clear) cysts. Inflammatory scores were higher in pericystic tissues from EB-stained cysts compared to clear cysts from untreated pigs and also from anthelmintic-treated pigs 48 hr and 120 hr after treatment. The degree of inflammation correlated with the severity of cyst wall damage and both increased significantly at 120 hours. Expression levels of the proinflammatory genes for IL-6, IFN-γ, TNF-α were higher in EB-stained cysts compared to clear cysts and unaffected brain tissues, and were generally highest at 120 hr. Additionally, expression of some markers of immunoregulatory activity (IL-10, IL-2Rα) were decreased in EB-stained capsules. An increase in other markers for regulatory T cells (CTLA4, FoxP3) was found, as well as significant increases in expression of two metalloproteases, MMP1 and MMP2 at 48 hr and 120 hr post-treatment. We conclude that the increase in severity of the inflammation caused by treatment is accompanied by both a proinflammatory and a complex regulatory response, largely limited to pericystic tissues with compromised vascular integrity. Because treatment induced inflammation occurs in porcine NCC similar to that in human cases, this model can be used to investigate mechanisms involved in host damaging inflammatory responses and agents or modalities that may control damaging post treatment inflammation.
    PLoS Neglected Tropical Diseases 03/2015; 9(3):e0003577. DOI:10.1371/journal.pntd.0003577 · 4.45 Impact Factor
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    ABSTRACT: The CRONICAS Centre of Excellence in Chronic Diseases, based at Universidad Peruana Cayetano Heredia, was created in 2009 with support from the U.S. National Heart, Lung, and Blood Institute (NHLBI). The vision of CRONICAS is to build a globally recognized center of excellence conducting quality and innovative research and generating high-impact evidence for health. The center's identity is embedded in its core values: generosity, innovation, integrity, and quality. This review has been structured to describe the development of the CRONICAS Centre, with a focus on highlighting the ongoing translational research projects and capacity-building strategies. The CRONICAS Centre of Excellence is not a risk-averse organization: it benefits from past experiences, including past mistakes, and improves upon them and thus challenges traditional research approaches. This ethos and environment are key to fostering innovation in research. Copyright © 2015 World Heart Federation (Geneva). All rights reserved.
    03/2015; 10(1):13-19. DOI:10.1016/j.gheart.2014.12.012
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    ABSTRACT: AbstracObjectives To examine the prevalence of seizures, epilepsy, and seropositivity to cysticercosis in rural villagers (cysticercosis-endemic setting), rural-to-urban migrants into a non-endemic urban shantytown, and urban inhabitants of the same non-endemic shanty town.Methods Three Peruvian populations (n=985) originally recruited into a study about chronic diseases and migration, were studied. These groups included rural inhabitants from an endemic region (n=200), long-term rural-to-urban migrants (n=589), and individuals living in the same urban setting (n=196). Seizure disorders were detected by a survey and a neurologist examined positive respondents. Serum samples from 981/985 individuals were processed for cysticercosis antibodies on immunoblot.ResultsEpilepsy prevalence (per 1,000 people) was 15.3 in the urban group, 35.6 in migrants, and 25 in rural inhabitants. A gradient in cysticercosis antibody seroprevalence was observed: urban 2%, migrant 13.5%, and rural group 18% (p<0.05). A similarly increasing pattern of higher seroprevalence was observed among migrants by age at migration. In rural villagers, there was strong evidence of an association between positive serology and having seizures (p=0.011) but such an association was not observed in long-term migrants or in urban residents. In the entire study population, compared to seronegative participants, those with strong antibody reactions (≥4 antibody bands) were more likely to have epilepsy (p<0.001).Conclusions It is not only international migration that affects cysticercosis endemicity; internal migration can also affect patterns of endemicity within an endemic country. The neurologic consequences of cysticercosis infection likely outlast the antibody response for years after rural-to-urban migration.This article is protected by copyright. All rights reserved.
    Tropical Medicine & International Health 01/2015; 20(4). DOI:10.1111/tmi.12456 · 2.33 Impact Factor
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    ABSTRACT: To develop a better understanding of mechanisms of seizures and long-term epileptogenesis using neurocysticercosis. A workshop was held bringing together experts in epilepsy and epileptogenesis and neurocysticercosis. Human neurocysticercosis and parallel animal models offer a unique opportunity to understand basic mechanisms of seizures. Inflammatory responses to degenerating forms and later-stage calcified parasite granulomas are associated with seizures and epilepsy. Other mechanisms may also be involved in epileptogenesis. Naturally occurring brain infections with neurocysticercosis offer a unique opportunity to develop treatments for one of the world's most common causes of epilepsy and for the development of more general antiepileptogenic treatments. Key advantages stem from the time course in which an acute seizure heralds a start of the epileptogenic process, and radiographic changes of calcification and perilesional edema provide biomarkers of a chronic epileptic state. Wiley Periodicals, Inc. © 2014 International League Against Epilepsy.
    Epilepsia 12/2014; 56(2). DOI:10.1111/epi.12849 · 4.57 Impact Factor
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    ABSTRACT: Neurocysticercosis is a leading cause of seizures and epilepsy in most of the world, and it occurs when Taenia solium larval cysts infect the central nervous system. T. solium tapeworm infection is endemic in much of Peru, but there are scarce data on the prevalence in many rural highland communities where it is likely to be hyper-endemic. Peace Corps Volunteers live and work in these communities; however, to our knowledge, they have not been used to facilitate public health research. We utilized Peace Corps Volunteers to estimate the prevalence of T. solium tapeworm infection in seven rural communities in northern Peru. A convenience non-random sampling frame was used. Peace Corps Volunteers facilitated the collection of stool samples (N = 2,328), which were analyzed by sedimentation and microscopy. Niclosamide treatment and purgation preceded species identification, which was done by PCR-REA. Taenia sp. egg-positive stool samples were found in three of the seven communities we surveyed. The overall prevalence of Taenia sp. egg positivity was 2.1% (49/2,328) (95% CI = 1.6-2.8%) with prevalence up to 4.3% (42/977) (95% CI = 3.1-5.8%) by community. All 34 of the specimens tested by PCR-REA were T. solium. The overall prevalence of T. solium tapeworm infection was 1.5% (34/2,328) (95% CI = 1.0-2.0%). Prevalence up to 2.9% (28/977) (95% CI = 1.9-4.1%) by community was observed. This study recorded high T. solium tapeworm prevalence, and identified hyper-endemic rural communities. It demonstrates that synergy between researchers and Peace Corps Volunteers can be an effective means to conducting large-scale, community-based studies in remote areas of Peru.
    PLoS ONE 12/2014; 9(12):e113239. DOI:10.1371/journal.pone.0113239 · 3.23 Impact Factor
  • Hector H Garcia · Theodore E Nash · Oscar H Del Brutto ·

    The Lancet Neurology 12/2014; 13(12):1173. DOI:10.1016/S1474-4422(14)70275-3 · 21.90 Impact Factor
  • Hector H Garcia · Theodore E Nash · Oscar H Del Brutto ·
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    ABSTRACT: The infection of the nervous system by the cystic larvae of Taenia solium (neurocysticercosis) is a frequent cause of seizure disorders. Neurocysticercosis is endemic or presumed to be endemic in many low-income countries. The lifecycle of the worm and the clinical manifestations of neurocysticercosis are well established, and CT and MRI have substantially improved knowledge of the disease course. Improvements in immunodiagnosis have further advanced comprehension of the pathophysiology of this disease. This knowledge has led to individualised treatment approaches that account for the involvement of parenchymal or extraparenchymal spaces, the number and form of parasites, and the extent of degeneration and associated inflammation. Clinical investigations are focused on development of effective treatments and reduction of side-effects induced by treatment, such as seizures, hydrocephalus, infarcts, and neuroinjury. Copyright © 2014 Elsevier Ltd. All rights reserved.
    The Lancet Neurology 12/2014; 13(12):1202-1215. DOI:10.1016/S1474-4422(14)70094-8 · 21.90 Impact Factor

  • Epilepsia 12/2014; 55(12). DOI:10.1111/epi.12899 · 4.57 Impact Factor
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    ABSTRACT: Calcified neurocysticercosis has been associated with hippocampal atrophy in patients with refractory epilepsy, but the relevance of this association in the population at large is unknown. We assessed calcified cysticerci and its association with hippocampal atrophy in elderly persons living in Atahualpa, an Ecuadorian village endemic for neurocysticercosis. All Atahualpa residents ≥ 60 years of age were invited to undergo computed tomography/magnetic resonance imaging for neurocysticercosis detection. Twenty-eight (11%) out of 248 enrolled persons had calcified cysticerci (case-patients) and were matched 1:1 by age, sex, and years of education to individuals without neurocysticercosis on computed tomography/magnetic resonance imaging (controls). Four case-patients and none of the controls had epilepsy (P = 0.134). Cognitive performance was similar across both groups. The Scheltens' medial temporal atrophy scale was used for hippocampal rating in case-patients and matched controls without neurocysticercosis. Mean score in the Scheltens' scale was higher in case-patients than in controls (p < 0.001). Atrophic hippocampi were noticed in 19 case-patients and five controls (P = 0.003). Atrophy was bilateral in 11 case-patients and unilateral in eight. All case-patients with unilateral hippocampal atrophy had at least one ipsilateral calcification. This study shows an association between calcified cysticerci and hippocampal atrophy and raises the possibility of an inflammation-mediated hippocampal damage as the responsible mechanism for these findings.
    The American journal of tropical medicine and hygiene 10/2014; 92(1). DOI:10.4269/ajtmh.14-0453 · 2.70 Impact Factor
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    ABSTRACT: Taenia solium infection causes severe neurological disease in humans. Even though infection and exposure to swine cysticercosis is scattered throughout endemic villages, location of the tapeworm only explains some of the nearby infections and is not related to location of seropositive pigs. Other players might be involved in cysticercosis transmission. In this study we hypothesize that pigs that carry nematodes specific to dung beetles are associated with cysticercosis infection and/or exposure. We carried out a cross-sectional study of six villages in an endemic region in northern Peru. We euthanized all pigs (326) in the villages and performed necropsies to diagnose cysticercosis. For each pig, we counted cysticerci; measured anti-cysticercus antibodies; identified intestinal nematodes; tabulated distance to nearest human tapeworm infection; and recorded age, sex, productive stage, and geographic reference. For the purpose of this paper, we defined cysticercosis infection as the presence of at least one cysticercus in pig muscles, and cysticercosis exposure as seropositivity to anti-cysticercus antibodies with the presence of 0-5 cysticerci. Compared to pigs without nematode infections, those pigs infected with the nematode Ascarops strongylina were significantly associated with the presence of cysticerci (OR: 4.30, 95%CI: 1.83-10.09). Similarly, pigs infected with the nematode Physocephalus sexalatus were more likely to have cysticercosis exposure (OR: 2.21, 95%CI: 1.50-3.28). In conclusion, our results suggest that there appears to be a strong positive association between the presence of nematodes and both cysticercosis infection and exposure in pigs. The role of dung beetles in cysticercosis dynamics should be further investigated.
    PLoS Neglected Tropical Diseases 10/2014; 8(10):e3247. DOI:10.1371/journal.pntd.0003247 · 4.45 Impact Factor

Publication Stats

7k Citations
1,628.68 Total Impact Points


  • 1991-2015
    • Universidad Peruana Cayetano Heredia
      • Facultad de Ciencia y Filosofía
      Λίμα, Lima, Peru
  • 2008-2014
    • Instituto Latinoamericano de Ciencias
      Λίμα, Lima, Peru
  • 2000-2014
    • Johns Hopkins University
      • Department of International Health
      Baltimore, Maryland, United States
    • Icahn School of Medicine at Mount Sinai
      Borough of Manhattan, New York, United States
    • Baylor College of Medicine
      • Section of Infectious Diseases
      Houston, TX, United States
  • 2012
    • Oregon Health and Science University
      • Department of Public Health & Preventive Medicine
      Portland, Oregon, United States
    • Pfizer Inc.
      New York, New York, United States
  • 1995-2011
    • National University of San Marcos
      • Facultad de Medicina Veterinaria
      Λίμα, Lima, Peru
  • 2010
    • Ministerio de Salud del Perú
      Λίμα, Lima, Peru
    • Georgia State University
      • Department of Biology
      Atlanta, Georgia, United States
  • 2008-2009
    • Johns Hopkins Bloomberg School of Public Health
      • Department of International Health
      Baltimore, Maryland, United States
  • 1991-2007
    • Centers for Disease Control and Prevention
      • Division of Parasitic Diseases and Malaria
      Атланта, Michigan, United States
  • 2006
    • University of Melbourne
      Melbourne, Victoria, Australia
  • 2005
    • National Institute of Health of Peru
      Λίμα, Provincia de Lima, Peru
  • 2002
    • Environmental Working Group
      Washington, Washington, D.C., United States