Regardless of the 90-day delay in Argentina, the tests remained stored according to the manufacturer’s instructions, and no break in the cold chain occurred during this period. In this study, the sensitivity and specificity of the Chagas Stat-Pak test using serum samples were 87% and 95%, respectively, which is less than those reported Gracillin in 6 independent studies conducted between 2003 and 2010 (26, 32,C37). Gracillin and provided an additional questionnaire to evaluate its ease of use. The selected RDTs in this study were performed under controlled laboratory conditions. Out of the 11 RDTs, we found 8 of them to be useful, with the cassette format favored over the strip. We did not observe significant differences in RDT performances in the different regions. Overall, the performance results were lower than those disclosed by the manufacturers. The results of this evaluation validate the possibility of using RDTs to diagnose Chagas disease, thereby decreasing the time to treatment at a primary health care facility for patients who are willing to be treated. Further studies should be conducted in the Gracillin laboratory and in the field to confirm these data, expressly to evaluate reproducibility in resource-limited settings, or using whole blood in clinical settings in areas of endemicity and nonendemicity. INTRODUCTION Chagas disease is one of the main public health problems in Latin America. It is estimated that between 8 and 11 million people (observe http://www.cdc.gov/chagas) have the disease and another 100 million are at risk of acquiring the disease (1). In recent decades, mainly due to populace movements, this general public health challenge has spread and is no longer limited to Latin America (2, 3); cases can also be found in the United States (4), Canada, Europe, and the Western Pacific region, mainly in Japan and Australia (5,C10). Diagnosis during the chronic phase is performed by detecting circulating contamination using whole blood, serum, or plasma samples are commercially available. Few of these assessments have been evaluated independently (not by the manufacturers). RDTs may be either qualitative or semiquantitative and are characterized by the delivery of quick results without the need for electrical equipment. In general, these assessments rely on different test principles: immunochromatography, particle agglutination, immunofiltration, or immunodot. Since 2007, in various forums, scientists and governmental and nongovernmental businesses have expressed the urgent need for new and simplified diagnostic tools, ideally through RDTs, to increase the diagnosis of contamination/Chagas disease and decrease the underdiagnosis in remote areas where the diagnosis is not accessible by standard techniques. These RDTs must be inexpensive and not require skilled laboratory staff, external gear, or refrigeration (18,C21). These assessments also must be highly sensitive, specific, and easy to use (22). The need for highly sensitive and specific RDTs was Gracillin reiterated in 2010 2010 when the 63rd World Health Assembly layed out, Gracillin through its resolution WHA63.20, the need to promote and encourage operational research on control of Chagas disease in order to establish systems of early detection and to integrate, at the primary health care level, diagnosis and treatment of Chagas disease in patients in both acute and chronic phases of the disease, in countries that are endemic and nonendemic for the disease (23). In recent years, several RDTs have been developed. However, to date, no independent overall performance evaluations have been conducted in different geographical areas. Therefore, in mid-2010, the WHO and Mdecins Sans Frontires (MSF) Technical Group III Diagnostic Chagas Disease decided to coordinate a multicenter study to evaluate the performances of all available commercialized RDTs using existing serum banks in national research laboratories (NRLs) in different geographical areas. MATERIALS AND METHODS Selection of RDTs. For inclusion in the study, a commercialized RDT experienced to meet some specific criteria. The test had to: be defined as a rapid test, be intended for routine diagnosis of contamination (not restricted to research use) by the manufacturer, generate results on the same day, not require a reader or other sophisticated instrumentation, be available for immediate purchase, and be manufactured with acknowledged quality certificates, such as CE mark, FDA-cleared, or p45 manufactured with ISO accreditation (24). A systematic review was conducted, and a total of 15 RDTs were found to be available from 14 different manufacturers. After contacting the respective manufacturers, 1 test was excluded.