Colorized scanning electron micrograph of Ebola virus particles in extracellular space between infected African green monkey kidney cells.
Early symptoms of Ebola virus disease (EVD), including fever, muscle pain, headache, and diarrhea, are often indistinguishable from symptoms of other diseases. However, EVD can progress to impaired kidney and liver function and internal and external bleeding. Because of the severity and high fatality rate, rapid and accurate diagnosis of Ebola infection is critical.
NIAID has supported the development of improved diagnostics to detect Ebola virus infection, including those that can provide rapid identification and can be deployed at the point-of-care where Ebola outbreaks occur. Two of these diagnostics became available under Emergency Use Authorization (EUA) by the Food and Drug Administration for detection of the Ebola Zaire strain during the 2014 West Africa outbreak.
The FilmArray Biothreat-E test, developed by BioFire Defense LLC, and the Xpert Ebola Test, manufactured by Cepheid, are polymerase chain reaction (PCR)-based tests that can detect viral nucleic acid in patient samples in less than two hours.
NIAID has provided support for FilmArray since 2005, with an initial focus on respiratory pathogen detection. From 2009 - 2012, NIAID supported the development of a biothreat panel, which included an Ebola diagnostic test. For the Xpert technology platform, NIAID initially funded basic science research for technology required for this diagnostic, supported the development of the Xpert for use as a diagnostic for tuberculosis, and provided funds to support an Xpert diagnostic for Ebola. The Biothreat E-test and Xpert Ebola Test received EUA in October 2014 and March 2015, respectively. Another FilmArray panel, the Global Fever Special Pathogens, can also detect Ebola. This test received FDA approval in March 2023.
NIAID also is advancing development of other types of diagnostics, including those using novel technologies, such as microfluidics, optofluidics, and nanophotonics, which are capable of detecting an array of viruses, including Ebola viruses. As a possible alternative to PCR-based tests, which require specialized equipment and personnel, NIAID is supporting development of sensitive lateral flow assays (LFA) for Ebola diagnosis. Lateral flow technology, which is also used in at-home COVID-19 antigen tests, is low cost and easy to use. With NIAID support, scientists are making progress developing highly sensitive rapid LFA-based tests for Ebola viruses that could be deployed in resource-constrained settings for surveillance, early diagnosis of infections, and contact tracing.