NEW YORK (GenomeWeb) – The US Food and Drug Administration (FDA) announced today that it is offering a panel of human plasma samples to assist in the regulatory evaluation of serological tests to detect recent Zika virus infection.
Two primary blood diagnostic tests currently exist: nucleic acid tests that detect infection by confirming the presence of a virus' RNA, and serological tests that identify antibodies that the body's immune system produces when it senses harmful organisms like Zika in the blood. Serological tests are especially crucial because there is frequently a small window of time when the virus' genetic material is even noticeable in the bloodstream.
Development of these types of tests have been challenging, however, because antibodies that the human body produces to fight Zika are difficult to tell apart from those produced to combat similar viruses, such as West Nile and dengue viruses.
"At the onset of the Zika virus outbreak, when little was known about the disease or how to diagnose it, the FDA worked quickly with manufacturers to encourage the development of diagnostic tests and ensure they were available using its Emergency Use Authorization," FDA Commissioner Scott Gottlieb said in a statement.
The FDA's panel contains plasma samples from anonymous individuals infected with Zika, West Nile, or dengue viruses. While the panel is not for research purposes, developers can take advantage of the samples to determine whether their tests can help identify recent Zika virus infection from its fellow viruses.
Using the same panel to assess different devices that are available under Emergency Use Authorization (EUA) will bolster public health professionals' efforts to compare the results of different Zika virus tests.
Developers who have interacted with the FDA through the pre-EUA process and have devices in the final stages of validation will have access to the FDA serology panel. As of now, the FDA has granted EUAs to three serological tests to detect recent Zika virus infections: Zika MAC-ELISA from the US Centers for Disease Control and Prevention; ZIKV Detect IgM Capture ELISA from InBios International, and Liaison XL Zika Capture IgM Assay from DiaSorin.
The FDA prepared the serological panel using samples from Zika virus-infected individuals provided by Blood Systems Research Institute from a study supported by the National Heart, Lung, and Blood Institute, and National Institutes of Health. The FDA obtained samples of dengue and West Nile virus-infected separately.
"By providing manufacturers of these tests with standardized patient samples to use in properly validating these diagnostics, we will be able to better assess how well their tests perform," Gottlieb added.