image: Performing the Toxoplasma ICT IgG-IgM test. view more
Credit: McLeod, et al. (2018)
Transmission of toxoplasmosis from mother to fetus can lead to severe congenital problems and fetal death, and tests for the parasitic infection during pregnancy are critical. Now, researchers reporting in PLOS Neglected Tropical Diseases have showed the efficacy of a low-cost whole blood test for toxoplasmosis.
Toxoplasmosis results from infection with the Toxoplasma gondii parasite, usually transmitted to humans from eating undercooked contaminated meat or through exposure to infected cat feces. Existing tests for the infection are serum tests, which require blood samples to be processed using infrastructure and technology which can be prohibitive in developing areas and unaffordable in developed countries like the United States.
Rima McLeod of the University of Chicago and her colleagues, including Joseph Lykins and Karen Leahy, tested 205 individuals. The individuals tested included patients, volunteers, and obstetrical patients from Chicago and Morocco known to be infected with T. gondii. A team led by coauthor Dr. El Bissati tested the pregnant patients in Morocco, and Dr. McLeod's team tested the patients in Chicago. The blood was tested for T. gondii infection status using reference tests, standard-of-care serum tests and the new whole-blood point-of-care (POC) test obtained by finger stick.
The whole blood POC test had 100% agreement with the reference and serum-variant testing, and proved highly sensitive and specific, with a sensitivity of 100% and a specificity of 100%. The scores held true even for women with lower levels of anti-Toxoplasma antibodies. However, the test cannot distinguish between acute and chronic infections.
The authors note, "Our work establishes a new point of care test in the outpatient setting at very low cost enabling diagnosis and prompt treatment for toxoplasma infections acquired for the first time during pregnancy. This enables life, sight and cognition saving treatments. If combined with multiplexed testing for other congenital infections and markers associated with premature birth, it will markedly improve maternal child outcomes and save lives."
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In your coverage please use this URL to provide access to the freely available paper: http://journals.plos.org/plosntds/article?id=10.1371/journal.pntd.0006536
Citation: Lykins J, Li X, Levigne P, Zhou Y, El Bissati K, et al. (2018) Rapid, inexpensive, fingerstick, whole-blood, sensitive, specific, point-of-care test for anti-Toxoplasmaantibodies. PLOS Neglected Tropical Diseases 12(8): e0006536. https://doi.org/10.1371/journal.pntd.0006536
Image Credit: McLeod, et al. (CC BY 4.0, 2018)
Image Caption: "Performing the Toxoplasma ICT IgG-IgM Test"
Funding: We gratefully acknowledge support of this work by the Thrasher Foundation (Award #- 13796) [Rima McLeod, Yvonne Maldonado, Jose G. Montoya, Despina G. Contopoulos-Ioannidis], NIH NIAID DMID R01 AI027530 [McLeod] and The Mann Cornwell, Van Dusen, Morel, Goldberg, Rooney, Taub, Drago, Orlinsky families. The work in Morocco was also funded, in part, by the Fulbright US Scholar Program [Kamal El Bissati]. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.
Competing Interests: The authors of this manuscript have the following competing interests: Dr. Rima McLeod worked on a literature review for Sanofi Pasteur.
Journal
PLoS Neglected Tropical Diseases