44 research outputs found

    Evaluation of the performance of Ortho T. cruzi ELISA test system for the detection of antibodies to Trypanosoma cruzi

    Get PDF
    The serologic diagnosis of chronic Chagas disease, caused by infection with the parasite Trypanosoma cruzi, is challenging and lacks a gold-standard assay. To overcome the problem, CDC uses an algorithm that uses two tests on different platforms and applies a third test as a tiebreaker. The Ortho T. cruzi ELISA Test System from Ortho Diagnostics was cleared by FDA for clinical diagnosis usage. We evaluated this test against the CDC algorithm for chronic Chagas disease. We tested several sets of serum specimens: 104 specimens tested positive for T. cruzi specific antibody and 283 (including 30 specimens positive for antibody to Leishmania spp.) tested negative based on the current CDC chronic T. cruzi infection diagnostic testing algorithm. Concordance of the Ortho T. cruzi ELISA Test System with the CDC algorithm result was 90% (95% CI 87 to 93%) overall and 92% (95% CI 89 to 95%) when excluding Leishmania spp. antibody positive specimens. The cross-reactivity of the Ortho T. cruzi ELISA Test System was 37% to Leishmania spp. serologically positive specimens, 1% to specimens from patients diagnosed with other parasitic infections, and 0% against specimens from a US noninfected population. In conclusion, the Ortho T. cruzi ELISA Test System compares well against the CDC diagnostic algorithm for chronic Chagas disease. The availability of this FDA-cleared assay will improve the chronic Chagas disease diagnosis. © 2022 American Society for Microbiology. All rights reserved

    Development of a rapid serological assay for the diagnosis of strongyloidiasis using a novel diffraction-based biosensor technology.

    Get PDF
    BACKGROUND: Strongyloidiasis is a persistent human parasitic infection caused by the intestinal nematode, Strongyloides stercoralis. The parasite has a world-wide distribution, particularly in tropical and subtropical regions with poor sanitary conditions. Since individuals with strongyloidiasis are typically asymptomatic, the infection can persist for decades without detection. Problems arise when individuals with unrecognized S. stercoralis infection are immunosuppressed, which can lead to hyper-infection syndrome and disseminated disease with an associated high mortality if untreated. Therefore a rapid, sensitive and easy to use method of diagnosing Strongyloides infection may improve the clinical management of this disease. METHODOLOGY/PRINCIPAL FINDINGS: An immunological assay for diagnosing strongyloidiasis was developed on a novel diffraction-based optical bionsensor technology. The test employs a 31-kDa recombinant antigen called NIE derived from Strongyloides stercoralis L3-stage larvae. Assay performance was tested using retrospectively collected sera from patients with parasitologically confirmed strongyloidiasis and control sera from healthy individuals or those with other parasitoses including schistosomiasis, trichinosis, echinococcosis or amebiasis who were seronegative using the NIE ELISA assay. If we consider the control group as the true negative group, the assay readily differentiated S. stercoralis-infected patients from controls detecting 96.3% of the positive cases, and with no cross reactivity observed in the control group These results were in excellent agreement (Îş = 0.98) with results obtained by an NIE-based enzyme-linked immunosorbent assay (ELISA). A further 44 sera from patients with suspected S. stercoralis infection were analyzed and showed 91% agreement with the NIE ELISA. CONCLUSIONS/SIGNIFICANCE: In summary, this test provides high sensitivity detection of serum IgG against the NIE Strongyloides antigen. The assay is easy to perform and provides results in less than 30 minutes, making this platform amenable to rapid near-patient screening with minimal technical expertise

    Schistosomiasis among Recreational Users of Upper Nile River, Uganda, 2007

    Get PDF
    After recreational exposure to river water in Uganda, 12 (17%) of 69 persons had evidence of schistosome infection. Eighteen percent self-medicated with praziquantel prophylaxis immediately after exposure, which was not appropriate. Travelers to schistosomiasis-endemic areas should consult a travel medicine physician

    Engaging the Imagination of Young People to Increase Technical Literacy

    Get PDF
    This paper examines the use of cognitive tools in designing an educational website that helps middle school learners improve their technological literacy. The Talk to Me website consists of a young adult novel, online activities that expand on concepts introduced in the novel, and a blog written by college engineering students about their experiences attending college and taking engineering courses. Talk to Me is designed using Imaginative Education, a learning theory developed by Kieran Egan that outlines learners\u27 different phases of development as their level of understanding and linguistic ability becomes more sophisticated. Beta testing occurred in 2010 with a group of elementary, middle, and high school teachers; the teachers responded with positive feedback, stating that they both could and would use Talk to Me in their classrooms. Additional testing with students in a summer robotics camp also supported the use of Talk to Me, showing that the website engaged students with concepts related to technological literacy

    Mysteries and Heroes: Using Imaginative Education to Engage Middle School Learners in Engineering

    Get PDF
    This paper examines the use of cognitive tools described in Imaginative Education (IE) in a middle school level engineering education project, Talk to Me. Developed by Kieran Egan, IE proposes five different levels of understandings, or ways of seeing and structuring the world, that develop at different cognitive and linguistic stages. The use of cognitive tools that assist learners with different understandings, such as narrative, engages these learners in a way that allows them to learn concepts more deeply. Talk to Me is aimed at middle school learners, primarily female students, in order to increase engagement from an early level and encourage further pursuit of engineering education. It consists of a young-adult novel, a website, a number of interactive activities that tie into the novel, and a blog where women in undergraduate engineering programs share their experiences. All parts of Talk to Me have been designed utilizing cognitive tools suggested by IE. Beta testing occurred in 2010 with a group of elementary, middle, and high school teachers; the teachers responded with positive feedback, stating that they both could and would use Talk to Me in their classrooms. These preliminary results indicate that IE can serve as an effective strategy for engaging learners in engineering
    corecore