Tropical Medicine Commons^™

Na-Gst-1 Adsorbed On Alhydrogel Co-Administered With Different Toll-Like Receptor Agonists In Hookworm-Naive Adults Using A Controlled Human Infection Model In The Usa: A Phase 2, Double-Blind, Randomised Controlled Trial, Caroline K Dirosato, Elissa M Malkin, Sean M Lee, Guacyara Erwin, Lara Hoeweler, Larissa Scholte, Maria Elena Bottazzi, David I Pritchard, Peter J Hotez, Jeffrey M Bethony, David J Diemert

Faculty, Staff and Students Publications

Background: Necator americanus glutathione S-transferase-1 (Na-GST-1) performs a crucial enzymatic step in hookworm blood feeding and is a leading target for vaccine development. Phase 1 trials in Brazil, Gabon, and the USA of recombinant Na-GST-1 adsorbed on Alhydrogel (Na-GST-1/Al), co-administered with or without AP 10-701 (Toll-like receptor [TLR] 4 agonist) or CpG 10104 (TLR9 agonist), showed the vaccine was well tolerated, safe, and immunogenic. A controlled human hookworm infection (CHHI) model was previously developed to evaluate the effect of candidate hookworm vaccines on infection. We aimed to assess the effect of vaccination with three different Na-GST-1 vaccine formulations on subsequent …

Modeling Reemergence Of Vaccine-Eliminated Infectious Diseases Under Declining Vaccination In The Us, Mathew V Kiang, Kate M Bubar, Yvonne Maldonado, Peter J Hotez, Nathan C Lo

Faculty, Staff and Students Publications

Importance: Widespread childhood vaccination has eliminated many infectious diseases in the US. However, vaccination rates are declining, and there are ongoing policy debates to reduce the childhood vaccine schedule, which may risk reemergence of previously eliminated infectious diseases.

Objective: To estimate the number of cases and complications in the US under scenarios of declining childhood vaccination for measles, rubella, poliomyelitis, and diphtheria.

Design, setting, and participants: A simulation model was used to assess the importation and dynamic spread of vaccine-preventable infectious diseases across 50 US states and the District of Columbia. The model was parameterized with data on area-specific estimates …

A Honduran Prevalence Study On Soil-Transmitted Helminths Highlights Serological Antibodies To Tm-Wap49 As A Diagnostic Marker For Exposure To Human Trichuriasis, Neima Briggs, Leroy Versteeg, Rojelio Mejia, Jeroen Pollet, Maria Jose Villar, Bin Zhan, Graeme Segal, Stephanie Novak, Patricia Lenihan, Paul Musgrave, Viviana Ellis, Carol Florencia Coello, K Jagannadha Sastry, Joe Craft, Peter J Hotez, Maria Elena Bottazzi

Faculty, Staff and Student Publications

Soil-transmitted helminth (STH) infections rank among the most prevalent communicable diseases of humans, yet detection of these parasites is mostly restricted to identifying active infection through fecal examinations. Currently, there are no commercial diagnostic tools to identify a prior whipworm or hookworm exposure, and the few serological assays for roundworm infection have not been well validated for crossreactivity or infections in humans. Such diagnostic restrictions limit the range of scientific and clinical questions that surround STH exposures and their implicated relationship to chronic diseases, such as autoimmunity, allergy, and cancer. The goal of this investigation was to evaluate the diagnostic …

Randomized, Observer-Blind, Controlled Phase 1 Study Of The Safety And Immunogenicity Of The Na-Gst-1/Alhydrogel Hookworm Vaccine With Or Without A Cpg Odn Adjuvant In Hookworm-Naïve Adults, David J Diemert, Maria Zumer, Mark Bova, Christina Gibbs-Tewary, Elissa M Malkin, Doreen Campbell, Lara Hoeweler, Guangzhao Li, Maria Elena Bottazzi, Peter J Hotez, Jeffrey M Bethony

Faculty, Staff and Students Publications

BACKGROUND: Recombinant Necator americanus Glutathione-S-Transferase-1 (Na-GST-1) formulated on Alhydrogel (Na-GST-1/Alhydrogel) is being developed to prevent anemia and other complications of N. americanus infection. Antibodies induced by vaccination with recombinant Na-GST-1 are hypothesized to interfere with the blood digestion pathway of adult hookworms in the host. Phase 1 trials have demonstrated the safety of Na-GST-1 formulated on Alhydrogel, but further optimization of the vaccine adjuvant formulation may improve humoral immune responses, thereby increasing the likelihood of vaccine efficacy.

METHODS: A randomized, observer-blind, dose escalation Phase 1 trial was conducted in 24 healthy, hookworm-naïve adults. In each cohort of 12 participants, 4 …

A Comparison Of The Diagnostic Capability Of Kato-Katz And Real-Time Pcr For The Assessment Of Treatment Efficacy Of Ivermectin And Albendazole Combination Against T Trichiura Infections, Gabriela Matamoros, Ana Sanchez, Ruben Cimino, Alejandro Krolewiecki, Rojelio Mejia

Faculty, Staff and Students Publications

BACKGROUND: Trichuris trichiura is humans' second most prevalent soil-transmitted helminth (STH) infection after Ascaris lumbricoides, affecting approximately 460 million people worldwide. Despite its sub-optimal sensitivity, especially in low prevalence and infection intensity settings, the modified Kato-Katz (K-K) is still recommended as a diagnostic method by the World Health organization (WHO) guidelines.

METHODOLOGY/PRINCIPAL FINDINGS: Within a randomized clinical trial (RCT) comprising four treatment arms with two different anthelmintics, the present study reports an important secondary research objective to determine the diagnostic agreement between K-K and real-time PCR evaluating treatment efficacy against T. trichiura. The parasitological results were analyzed, including cure rates …

Molecular Detection Of Intestinal Parasites In A Rural Community Of Colombia: A One Health Approach To Explore Potential Environmental-Zoonotic Transmission, Sergio Castañeda, Claudia Patricia Acosta, Luis Reinel Vasquez-A, Luz H Patiño, Rojelio Mejía, Juan David Ramírez

Faculty, Staff and Students Publications

Aims: Protozoan and helminth parasitic infections pose significant public health challenges, especially in developing countries with rural populations marked by suboptimal hygiene practices and socio-economic constraints. The parasites are the etiological agents of these infections and have a notably elevated global prevalence. Therefore, this study focuses on estimating the frequency and transmission dynamics of several parasitic species, including Blastocystis, Giardia, Cryptosporidium spp., Entamoeba histolytica, Ascaris lumbricoides, Trichuris trichiura, Taenia spp. and hookworms, within a rural community in southwest Colombia with a particular emphasis on the One Health framework, considering environmental and zoonotic transmission potentials.

Methods and results: This study involved …

Analysis Of The Immunological Biomarker Profile During Acute Zika Virus Infection Reveals The Overexpression Of Cxcl10, A Chemokine Linked To Neuronal Damage., Felipe Gomes Naveca, Gemilson Soares Pontes, Aileen Yu-Hen Chang, George Allan Villarouco Da Silva, Valdinete Alves Do Nascimento, Dana Cristina Da Silva Monteiro, +Several Additional Authors

Medicine Faculty Publications

BACKGROUND: Infection with Zika virus (ZIKV) manifests in a broad spectrum of disease ranging from mild illness to severe neurological complications and little is known about Zika immunopathogenesis.

OBJECTIVES: To define the immunologic biomarkers that correlate with acute ZIKV infection.

METHODS: We characterized the levels of circulating cytokines, chemokines, and growth factors in 54 infected patients of both genders at five different time points after symptom onset using microbeads multiplex immunoassay; comparison to 100 age-matched controls was performed for statistical analysis and data mining.

FINDINGS: ZIKV-infected patients present a striking systemic inflammatory response with high levels of pro-inflammatory mediators. Despite …