Martin Casapia

• MD, MPH
• Principal Investigator at Asociacion Civil Selva Amazonica. Universidad Nacional de la Amazonia. Hospital Regional de Loreto

Strongyloides stercoralis infections, human T-lymphotropic virus (HTLV) infections, and Chagas diseases occur throughout many regions of Central and South America, including Peru. This study aimed to evaluate the seroprevalence of S. stercoralis, HTLV, and Chagas disease in Iquitos (Peruvian Amazon) and the associated epidemiological conditions for...

Capillary leak syndrome is a unique complication characterized by extravasation of liquids in the interstitial space due to protein loss caused by snakebite envenoming. We describe the case of a 12-year-old boy from the district of Napo in the city of Iquitos in the Peruvian Amazon, who had edema and increased face volume due to the bite of a snake...

In the ENSEMBLE randomized, placebo-controlled phase 3 trial (NCT04505722), estimated single-dose Ad26.COV2.S vaccine efficacy (VE) was 56% against moderate to severe–critical COVID-19. SARS-CoV-2 Spike sequences were determined from 484 vaccine and 1,067 placebo recipients who acquired COVID-19. In this set of prespecified analyses, we show that i...

Background The study of the etiology of acute febrile illness (AFI) has historically been designed as a prevalence of pathogens detected from a case series. This strategy has an inherent unrealistic assumption that all pathogen detection allows for causal attribution, despite known asymptomatic carriage of the principal causes of acute febrile illn...

It is of interest to pinpoint SARS-CoV-2 sequence features defining vaccine resistance. In the ENSEMBLE randomized, placebo-controlled phase 3 trial, estimated single-dose Ad26.COV2.S vaccine efficacy (VE) was 56% against moderate to severe–critical COVID-19. SARS-CoV-2 Spike sequences were measured from 484 vaccine and 1,067 placebo recipients who...

The objective of this manuscript is to provide selective examples of the work of the Pan American Health Organization/World Health Organization (PAHO/WHO) Collaborating Centre for Research and Training in Parasite Epidemiology and Control which contribute to the WHO goal of eliminating neglected tropical diseases by 2030. This PAHO/WHO CC specifica...

Background: The study of the etiology of acute febrile illness (AFI) has historically been designed as a prevalence of pathogens detected from a case series. This strategy has an inherent unrealistic assumption that all pathogen detection allows for causal attribution, despite known asymptomatic carriage of the principal causes of acute febrile ill...

BACKGROUND. Tenofovir-based daily oral HIV pre-exposure prophylaxis (HIV PrEP) is a highly efficacious HIV prevention modality, but sustained use over time isneeded for continued protection among individuals at high risk for HIV exposure. Suboptimal adherence and retention in care threaten to diminish theimpact of HIV PrEP on reducing HIV burden. P...

Stunting, anemia, and soil-transmitted helminth (STH) infections are major health concerns for children in extremely poor regions of the world, especially rural and periurban ones. This study aimed to determine the prevalence of these three cooccurring conditions in preschool-age children in an extremely poor district on the outskirts of Iquitos, i...

Plasmodium vivax causes 81% of all malaria cases and is the most common species in the Peruvian Amazon. We present the case of a male patient with cerebral malaria caused by Plasmodium vivax, who had general malaise and fever, and then presented seizures more than twice a day with loss of consciousness and motor functional limitation. Plasmodium vi...

Background People infected with Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) experience a wide range of clinical manifestations, from asymptomatic and mild illness to severe illness and death, influenced by age and a variety of comorbidities. Neutralizing antibodies (nAbs) are thought to be a primary immune defense against the virus...

Correct processing of blood cultures may impact individual patient management, antibiotic stewardship, and scaling up of antimicrobial resistance surveillance. To assess the quality of blood culture processing, we conducted four assessments at 16 public hospitals across different regions of Peru. We assessed the following standardized quality indic...

Background Strongyloidiasis is a disease of great public health significance, caused by the parasitic nematodes Strongyloides stercoralis, Strongyloides fuelleborni, and Strongyloides fuelleborni subsp. kellyi. This systematic review and meta-analysis aimed to assess the prevalence of Strongyloides stercoralis infection in Peru. Methods The review...

Background: Eliciting durable humoral immunity with sufficient breadth and magnitude is important for HIV-1 vaccine design. The HVTN 114 vaccine trial evaluated different boost regimens administered after a 7-year rest period in participants previously enrolled in HVTN 205, who received either three MVA/HIV62B (MMM) or two DNA and two MVA/HIV62B (...

The World Health Organization recommends deworming to reduce soil‐transmitted helminth (STH)‐attributable morbidity in women of reproductive age, including pregnant and lactating women, to reduce blood loss, iron deficiency anaemia and nutrient malabsorption. This study assessed the impact of maternal postpartum deworming with albendazole approxima...

Background. Human T-cell lymphotropic virus type 1 (HTLV-1) is responsible for tropical spastic paraparesis and HTLV-1-associated leukemia/lymphoma. The infection is endemic in some areas of Peru, but its prevalence in the Peruvian Amazon is not well established. We aimed to assess the seroprevalence of HTLV-1 infection in pregnant women in the Per...

Strongyloidiasis is a disease of great public health significance. We aimed to assess the prevalence of Strongyloides stercoralis infection in Peru. Methods. This systematic review was based on a literature search in PubMed, SciELO and Google Scholar using the key words or root words “strongyl*” AND “Peru” on 15 July 2020. Eligible studies were pub...

Aims: To assess the prevalence of Chagas disease in pregnant women in Iquitos City, Peru. Material and Methods: Cross-sectional survey in 300 pregnant women in Iquitos (Peru) from 1 May 2019 to 15 June 2019. Women were tested using an ELISA serology test. Results: Serology was positive in one case (prevalence: 0.33%; 95% confidence interval: 7.1–13...

Background. Multi-drug resistant falciparum malaria is an important health problem in the Peruvian Amazon region. We carried out a randomised open label clinical trial comparing mefloquine-artesunate, the current first line treatment in this region, with dihydroartemisinin-piperaquine. Methods and Findings. Between July 2003 and July 2005, 522 pati...

Strongyloidiasis is a soil-transmitted helminthiasis with a high global prevalence. Objectives: We aimed to evaluate the prevalence of Strongyloides stercoralis infection and assess strongyloidiasis serology as a screening technique in the Peruvian Amazon. Material and methods: We performed a cross-sectional study of strongyloidiasis in 300 pre...

Background Large-scale deworming programs have, to date, mostly targeted preschool- and school-age children. As community-based deworming programs become more common, deworming will be offered to women of reproductive age. The World Health Organization recommends preventive chemotherapy be administered to pregnant women only after the first trimest...

T cell responses have been implicated in reduced risk of HIV acquisition in uninfected persons and control of viral replication in HIV-infected individuals. HIV Gag-specific T cells have been predominantly associated with post-infection control, whereas Env antigens are the target for protective antibodies; therefore, inclusion of both antigens is...

Background The Antibody-mediated Prevention (AMP) trials (HVTN 704/HPTN 085 and HVTN 703/HPTN 081) are the first efficacy trials to evaluate whether VRC01, a broadly neutralizing antibody (bnAb) that targets CD4 binding site of HIV envelope, prevents HIV acquisition in uninfected individuals. In these ongoing trials, 10 intravenous (IV) infusions o...

Introduction Developing guidelines to inform the use of antiretroviral pre-exposure prophylaxis (PrEP) for HIV prevention in resource-limited settings must necessarily be informed by considering the resources and infrastructure needed for PrEP delivery. We describe an approach that identifies subpopulations of cisgender men who have sex with men (M...

Background: Soil-transmitted helminth infections have been found to be associated with child development. The objective was to investigate hemoglobin levels and malnutrition as mediators of the association between Ascaris infection and intelligence quotient (IQ) scores in children. Methodology: We conducted a longitudinal cohort study in Iquitos...

Background: Treatment of Plasmodium vivax malaria requires the clearing of asexual parasites, but relapse can be prevented only if dormant hypnozoites are cleared from the liver (a treatment termed "radical cure"). Tafenoquine is a single-dose 8-aminoquinoline that has recently been registered for the radical cure of P. vivax. Methods: This mult...

BACKGROUND Tafenoquine, a single-dose therapy for Plasmodium vivax malaria, has been associated with relapse prevention through the clearance of P. vivax parasitemia and hypnozoites, termed “radical cure.” METHODS We performed a phase 3, prospective, double-blind, double-dummy, randomized, controlled trial to compare tafenoquine with primaquine in...

Background: Anemia is a term that describes low hemoglobin concentrations and can result from micronutrient deficiencies, infection, or low birth weight. Early-life anemia, particularly iron-deficiency anemia (IDA) is associated with several negative metabolic, developmental, and cognitive outcomes, some of which persist into adulthood. Objective...

Background Soil-transmitted helminth (STH) infection leads to malnutrition and anemia, and has been linked to impaired child development. Previous research on this topic is limited and mostly conducted in school-age children. The goal of this study was to determine the effect of the number of detected STH infections between one and two years of age...

STROBE statement. Checklist for reports of observational studies. (PDF)

Background: Limited research has documented an association between soil-transmitted helminth (STH) infections and child development. This has recently been identified as an important knowledge gap. Methods: A longitudinal cohort study was conducted in Iquitos, Peru, between September 2011 and July 2016. A cohort of 880 children, recruited at 1 y...

Background: DSM265 is a novel, long-duration inhibitor of plasmodium dihydroorotate dehydrogenase (DHODH) with excellent selectivity over human DHODH and activity against blood and liver stages of Plasmodium falciparum. This study aimed to assess the efficacy of DSM265 in patients with P falciparum or Plasmodium vivax malaria infection. Methods:...

Diffuse multibacillary leprosy of Lucio and Latapí is mainly reported in Mexico and Central America. We report a case in a 65-year-old man in Peru. He also had Lucio’s phenomenon, characterized by vascular thrombosis and invasion of blood vessel walls by leprosy bacilli, causing extensive skin ulcers. © 2017, Centers for Disease Control and Prevent...

Exchange sex and higher education were associated with an increased likelihood of international sexual partnerships (ISPs). Exchange sex and older age were associated with an increased likelihood of condomless sex in ISPs. Educational and socioeconomic factors may create unbalanced power dynamics that influence exchange sex and condomless sex in IS...

Objective To identify determinants which influence the timing of the first antenatal care (ANC) visit in pregnant women. Design Retrospective matched nested case-control study. Setting Two health centres, Belén and 6 de Octubre, in the Peruvian Amazon. Population All pregnant women who had attended ANC during the years 2010, 2011, and 2012. Met...

Proportions of pregnancies of early adolescent, late adolescent and adult women, by trimester at first ANC visit, in the community of Belén, Iquitos, Peru, 2010 to 2012. (TIF)

Results of matching controls to cases on health centre and date of first ANC visit, Belén, Iquitos, Peru, 2010–2012. (DOCX)

Case Control Final Dataset. (XLS)

Proportions of all pregnancies of women attending their first ANC visit, by trimester, at Belén Health Centre and 6 de Octubre Health Centre, Iquitos, Peru, 2010–2012. (DOCX)

Codebook for Case Control Final Dataset. (XLSX)

Background Nutritional interventions targeting the critical growth and development period before two years of age can have the greatest impact on health trajectories over the life course. Compelling evidence has demonstrated that interventions investing in maternal health in the first 1000 days of life are beneficial for both mothers and their chil...

Effect of maternal postpartum deworming on infant morbidity indicators at 6 months of age, per-protocol analysis (N = 939*), Iquitos, Peru (February 2014 –February 2015). (DOCX)

Effect of maternal postpartum deworming on prevalence of infant underweight, wasting, and stunting at 6 month of age, complete-case analysis (N = 972*), Iquitos, Peru (August 2014 –February 2015). (DOCX)

Effect of maternal postpartum deworming on infant anthropometric outcomes over their first 6 months of life, per-protocol analysis (n = 939*), Iquitos, Peru (February 2014 –February 2015). (DOCX)

Effect of maternal postpartum deworming on prevalence of infant underweight, wasting, and stunting at 6 month of age, per-protocol analysis (N = 939*), Iquitos, Peru (August 2014 –February 2015). (DOCX)

Effect of maternal postpartum deworming on prevalence of infant underweight, wasting, and stunting at 1 month of age (N = 1010*), Iquitos, Peru (March–September 2014). (DOCX)

Effect of maternal postpartum deworming on infant morbidity indicators at 6 months of age, complete-case analysis (N = 972*), Iquitos, Peru (February 2014 –February 2015). (DOCX)

(DOCX)

Effect of maternal postpartum deworming on infant anthropometric outcomes over their first 6 months of life, complete-case analysis (n = 972*), Iquitos, Peru (February 2014 –February 2015). (DOCX)

Effect of maternal postpartum deworming on prevalence of infant underweight and stunting at 6 month of age in women who tested positive for infection with any helminth species at baseline (N = 139*), Iquitos, Peru (August 2014 –February 2015). (DOCX)

Effect of maternal postpartum deworming on infant morbidity indicators at 1 month of age (N = 1010*), Iquitos, Peru, (March–September 2014). (DOCX)

Baseline characteristics of participants who completed the 6-month visit (n = 972) compared to those who were lost to follow-up at 6 months (n = 38), Iquitos, Peru (February–August 2014). (DOCX)

Effect of maternal postpartum deworming on infant anthropometric outcomes over their first month of life (N = 1010*), Iquitos, Peru (February–September 2014). (DOCX)

Effect of maternal postpartum deworming on infant morbidity indicators at 6 months of age in women who tested positive for infection with any helminth species at baseline (N = 139*), Iquitos, Peru (February 2014 –February 2015). (DOCX)

Background: In Peru, 11% of deaths are due to trauma. Iquitos is a large underserved Peruvian city isolated from central resources by its geography. Our objective was to implement a locally driven trauma registry to sustainably improve trauma healthcare in this region. Methods: All trauma patients presenting to the main regional referral hospital w...

Background: As pre-exposure prophylaxis (PrEP) with tenofovir disoproxil fumarate and emtricitabine for the prevention of HIV infection is rolled out internationally, strategies to maintain effectiveness and to minimise adverse effects merit consideration. In this study, we aimed to assess reductions in renal function and predictors of renal toxic...

Large-scale deworming interventions, using anthelminthic drugs, are recommended in areas where the prevalence of soil-transmitted helminth infection is high. Anthelminthic safety has been established primarily in school-age children. Our objective was to provide evidence on adverse events from anthelminthic use in early childhood. A randomized mult...

Chau Cuica was the name given by the regional government of Loreto in Peru for its school-based deworming program which was initiated in 2012 with a donation of mebendazole from an international non-governmental organization. Embedded in the program from the start was a sentinel surveillance component which consisted of 16 sentinel schools represen...

Background: There is a knowledge gap on the effect of early childhood deworming on development in low- and middle-income countries. This evidence is important in the critical window of growth and development before two years of age. Methods: A randomized controlled trial of the benefit, and optimal timing and frequency, of deworming on development...

Background: Appropriate health and nutrition interventions to prevent long-term adverse effects in children are necessary before two years of age. One such intervention may include population-based deworming, recommended as of 12 months of age by the World Health Organization in soil-transmitted helminth (STH)-endemic areas; however, the benefit o...

The Cochrane Library has recently published a 160-page, updated systematic review on deworming drugs for soil-transmitted intestinal worms in children, which concludes, “Treating children known to have worm infection may have some nutritional benefits for the individual. However, in mass treatment of all children in endemic areas, there is now subs...

The World Health Organization currently recommends that school-based deworming programs include health hygiene education as a complementary measure. However, the sustainability and long-term impact of such hygiene education had yet to be assessed. In July 2012, this cross-sectional study was conducted in 18 primary schools in the Peruvian Amazon to...

Introduction Soil-transmitted helminth infections are endemic in 114 countries worldwide, and cause the highest burden of disease among all neglected tropical diseases. The WHO includes women of reproductive age as a high-risk group for infection. The primary consequence of infection in this population is anaemia. During lactation, anaemia may cont...

Background Children under two years of age are in the most critical window for growth and development. As mobility increases, this time period also coincides with first exposure to soil-transmitted helminth (STH) infections in tropical and sub-tropical environments. The association between malnutrition and STH infection, however, has been understud...

Background The effect of HIV pre-exposure prophylaxis (PrEP) depends on uptake, adherence, and sexual practices. We aimed to assess these factors in a cohort of HIV-negative people at risk of infection. Methods In our cohort study, men and transgender women who have sex with men previously enrolled in PrEP trials (ATN 082, iPrEx, and US Safety Stu...

Soil-transmitted helminth (STH) infections are a leading cause of disability and disease burden in school-age children of worm-endemic regions. Their effect on school absenteeism, however, remains unclear. The World Health Organization currently recommends delivering mass deworming and health hygiene education through school-based programs, in an e...

In addition to protecting against HIV acquisition, antiretroviral preexposure prophylaxis (PrEP) using topical 1% tenofovir gel reduced Herpes simplex virus type 2 (HSV-2) acquisition by 51% among women in the CAPRISA 004 study. We examined the effect of daily oral emtricitabine/tenofovir (FTC/TDF) PrEP on HSV-2 seroincidence and ulcer occurrence a...

Objectives: To determine the efficacy of single-dose albendazole (400 mg) for soil-transmitted helminth infections (STH) in schoolchildren living in one community of the city of Iquitos, Perú. Materials and methods: Within the context of a randomized controlled trial performed in a peri-urban community of limited resources located in Iquitos in...

Objectives. To determine the efficacy of single-dose albendazole (400 mg) for soil-transmitted helminth infections (STH) in schoolchildren living in one community of the city of Iquitos, Perú. Materials and methods. Within the context of a randomized controlled trial performed in a peri-urban community of limited resources located in Iquitos in th...

Dengue fever is the world's most important arboviral disease, presenting a wide clinical spectrum. We report for the first time in Peru, a case caused by dengue virus serotype 4 with significant gastrointestinal involvement (acute acalculous cholecystitis and acute hepatitis). In addition we carried out a review of the literature atypical presentat...

Objetivos. Determinar la eficacia en dosis única del albendazol sobre las infecciones por helmintos transmitidos por el suelo (HTS) en escolares de una comunidad de la ciudad de Iquitos en Perú. Materiales y métodos. Dentro del contexto de un ensayo controlado aleatorizado realizado en una comunidad periurbana de escasos recursos, situada en Iquito...

El dengue es la arbovirosis más importante del mundo y causa un amplio espectro clínico. Presentamos el primer caso de dengue causado por el serotipo 4 (DENV-4) en Perú con compromiso gastrointestinal (colecistitis aguda alitiásica y hepatitis aguda moderada). Se presenta una revisión de la literatura médica sobre este tipo de presentación, enfatiz...

To control soil-transmitted helminth (STH) infections, the World Health Organization recommends school-based deworming programs with a health hygiene education component. The effect of such health hygiene interventions, however, has not been adequately studied. The objective of the present study was to determine the effectiveness of a health hygien...

Dengue fever is the world's most important arboviral disease, presenting a wide clinical spectrum. We report for the first time in Peru, a case caused by dengue virus serotype 4 with significant gastrointestinal involvement (acute acalculous cholecystitis and acute hepatitis). In addition we carried out a review of the literature atypical presentat...

Objective: Oral preexposure prophylaxis (PrEP) with antiretrovirals (ARVs) is at the forefront of biomedical HIV prevention research, and ARVs are also being tested for rectal administration to target people practicing unprotected receptive anal intercourse (URAI) and at risk of HIV infection. This study assessed the acceptability of daily oral Pr...

The tourniquet test (TT) is a physical examination maneuver often performed on patients suspected of having dengue. It has been incorporated into dengue diagnostic guidelines and is used in clinical studies. However, little is known about TT performance characteristics in different patient types or epidemiologic conditions. In the dengue-endemic ci...

Evidence from randomized controlled trials has shown that delayed cord-clamping is beneficial to infant iron status. The role of maternal anaemia in this relationship, however, has not been established. To determine the effect of maternal anaemia at delivery on the association between timing of umbilical cord-clamping and infant anaemia at 4 and 8...

Background Knowledge of a sex partner’s HIV serostatus can influence sexual behavior and inform harm-reduction strategies. We sought to determine how often Peruvian men who have sex with men (MSM) and transgender women (TW) knew the HIV serostatus of their sex partners, if this knowledge was associated with any predictive factors or unprotected ana...

Background: Knowledge of a sexual partner’s HIV and serostatus can influence sexual behavior and inform harm-reduction strategies. We sought to determine how often Peruvian men who have sex with men (MSM) and transgender women (TW) know their sexual partners’ HIV test results. Methods: We analyzed data from the 2008 Peruvian Sentinel Surveillance...

Drug concentrations associated with protection from HIV-1 acquisition have not been determined. We evaluated drug concentrations among men who have sex with men in a substudy of the iPrEx trial (1). In this randomized placebo-controlled trial, daily oral doses of emtricitabine/tenofovir disoproxil fumarate were used as pre-exposure prophylaxis (PrE...