Investment

Details

Field validation of Trypanosoma cruzi-LAMP: a molecular point-of-care test for the control of congenital Chagas disease
  • RFP Year
    2020
  • Awarded Amount
    $1,471,273
  • Disease
    NTD (Chagas disease)
  • Intervention
    Diagnostic
  • Development Stage
    Product Validation
  • Collaboration Partners
    Eiken Chemical Co., Ltd., Centro para el Desarrollo de Investigación Científica (CEDIC) , Ciencia y Estudios Aplicados Para el Desarrollo en Salud y Medio Ambiente (CEADES) , AI Biosciences Inc. , Fundacion Mundo Sano, Instituto de Investigaciones en Ingeniería Genética y Biología Molecular (CONICET-INGEBI), Nagasaki University, Barcelona Institute for Global Health (ISGLOBAL)

Introduction and Background of the Project

Introduction

Chagas disease, caused by the protozoan parasite Trypanosoma cruzi, affects ~7 million people, mostly in Latin America. Vector-borne transmission is on the way of being controlled in several countries, but vertical transmission remains an uncontrolled major public-health challenge. Remarkably, available drugs have a very high cure rate in T. cruzi-infected newborns if administered early upon infection, thus a timely diagnose is crucial for treatment success. However, the algorithm to detect congenital T. cruzi infection involves parasitological methods that lack sensitivity and a serological study must be performed several months later. In many endemic regions people live far from referral centers which entails that a large proportion of infants rarely go back for diagnosis confirmation and treatment, if infected. Consequently, they evolve to the chronic phase of the disease with the risk of developing severe manifestations.

Molecular-based diagnostics have a very high sensitivity to detect congenital T. cruzi infections, but laboratories in those distant regions are not equipped to perform them. With the aim to provide a suitable point-of-care (POC) test for the timely diagnosis of congenital Chagas disease in these settings, we will validate the implementation of EIKEN T. cruzi loop-mediated isothermal amplification (LAMP) prototype in the field.

 

 

Project objective

Objectives of this project are to: 1) conduct an analytical evaluation of the most suitable DNA isolation methodology for implementing T. cruzi-LAMP as POC test for timely diagnosis of congenitally acquired T. cruzi infection; 2) evaluate operationally its use in maternity hospitals from Chagas disease endemic regions of Argentina, Bolivia and Paraguay; 3) validate in a wide geographical area the use of rapid diagnostic tests (RDTs) as an alternative to conventional enzyme-linked immunosorbent assays (ELISAs) to detect chronic T. cruzi infections; and 4) perform information, education and communication (IEC) and advocacy activities to increase disease awareness and facilitate the potential acceptance and adoptability of the technologies under research by the communities and authorities where the project will be developed.

 

Project design

We will work in hospitals with maternity wards in Argentina, Bolivia and Paraguay. Infants enrolled will follow current algorithm to diagnose congenital Chagas comprising two microscopy-based observations of parasite presence in peripheral blood at birth and a few months later, and a serological study by nine months of age. Whole blood samples will be obtained at those time-points and stored until needed. In parallel to the recruitment, we will determine the best conditions for implementing EIKEN T. cruzi-LAMP prototype as POC diagnostic, including the evaluation of two techniques to provide the required purified DNA for the reaction: AI Biosciences low-cost 3D printer-inspired platform and EIKEN PURE (Procedure for Ultra Rapid Extraction) system. The most suitable for field use accompanying LAMP will be chosen, bearing in mind their performance and operational parameters like ease of use.

As part of the project, we will also compare the performance of RDTs for the detection of chronic T. cruzi-infected mothers with that of ELISAs. Rationale for the use of RDTs stands on our previous experience in the Bolivian Chaco, where they proved to be highly sensitive and their quick results turnaround allowed swift recruitment of study participants.

According to Chagas disease prevalence reports in the study regions, and an average vertical transmission rate of ~5%, we will need to screen ~16,000 women (mean prevalence of chronic Chagas disease 17.2%) so as to enroll the newborns of those T. cruzi-infected (~2,800). During the second year we will follow the infants and run the T. cruzi-LAMP tests. In addition to current congenital Chagas algorithm, their performance will be compared to that of a standard qPCR molecular-based technique.

How can your partnership (project) address global health challenges?

Chagas disease persists as a major public health challenge. It is endemic to 21 countries in Latin America and causes a greater burden of disability-adjusted life years than any other parasitic disease in the Americas. It is estimated to affect ~7 million people worldwide, but global surveillance and reporting of infection and disease rates are largely inadequate, due in part to the need for improved diagnostic tools. Mother to child transmission of T. cruzi infection is considered to be “a continuous source of infected newborns, even with complete control of vector and transfusion-mediated transmission”. According to PAHO, an estimated 1.12 million women of childbearing age are infected, and around 9,000 infected babies are born each year, accounting for more than 20% of all new cases in the region. Thus, congenital parasite transmission has implications in terms not only for individual health, but also for global public health. The validation of highly sensitive and specific diagnostics that provide an early access to diagnosis for mothers and newborns will contribute to control the disease impact.

What sort of innovation are you bringing in your project?

The project is designed as an integrated process whereby each of the eight intervention sites will serve as a recruitment center for validation of diagnostic tests, while at the same time will function as a community engagement focus. In the course of the process, we will validate and implement improved algorithms for rapid and reliable diagnosis of pregnant women and newborns. In this regards, validating the use of RDTs for the screening of mothers and taking T. cruzi-LAMP to license gate for its widespread implementation in maternity hospitals represent two major breakthroughs. Diagnosis of infected mothers by ELISAs in endemic regions is subject to delays in results turnaround and often occurs that the mother is unaware of her chronic T. cruzi infection status at the time of delivery. For the newborn, the algorithm to detect congenital infection is lengthy and usually takes several months for serological confirmation with a very high risk of loss to follow-up. Thus, counting with rapid and accurate point-of-care diagnostics will really make the difference.

Role and Responsibility of Each Partner

ISGlobal will coordinate the project being as well responsible for the data management and analysis. EIKEN Chemical Co. will provide its expertise on T. cruzi-LAMP technique and DNA isolation with PURE reagent, while AI Biosciences, Inc. will participate with its low-cost 3D printer-inspired platform to work as a nucleic acids isolation station. CONICET-INGEBI will perform the analytical evaluation to select the best nucleic acids isolation technique to couple to T. cruzi-LAMP, plus it will be the referral laboratory for molecular biology and will transfer the LAMP to the field. Fundacion Mundo Sano, CEADES, University of Nagasaki and CEDIC will be implementing partners, respectively in Argentina, Bolivia and Paraguay. They will enroll and follow all study participants, performing the required serological assays to compare RDTs with ELISAs, as well as they will run the LAMP assays for comparison with currently used congenital Chagas diagnosis algorithm.

Others (including references if necessary)

Besuschio SA et al. Analytical sensitivity and specificity of a loop-mediated isothermal amplification (LAMP) kit prototype for detection of Trypanosoma cruzi DNA in human blood samples. PLoS Negl Trop Dis (2017) 11:e0005779.

Alonso-Padilla J, et al. Strategies to enhance access to diagnosis and treatment for Chagas disease patients in Latin America. Expert Rev Anti Infect Ther (2019) 17(3):145-157.

Lozano D, et al. Use of rapid diagnostic tests (RDTs) for conclusive diagnosis of chronic Chagas disease – a field study in the Bolivian Chaco region. PLoS Negl Trop Dis (2019) 13:e0007877. 

Besuschio SA et al. Trypanosoma cruzi loop-mediated isothermal amplification (Trypanosoma cruzi Loopamp) kit for detection of congenital, acute and Chagas disease reactivation. PLoS Negl Trop Dis (2020) 14:e0008402.

Wehrendt DP et al. Development and evaluation of a 3D Printer-based DNA extraction method coupled to loop mediated isothermal amplification (LAMP) for point-of-care diagnosis of congenital Chagas disease in endemic regions. J Mol Diagn (2020) S1525-1578(20)30615-2.