- Zika MAC-ELISA is an antibody-based diagnostic developed by the Centers for Disease Control and Prevention (CDC). Antibodies can be detected either in blood or cerebrospinal fluid.
- The Zika virus, which has been linked to perinatal cases of microcephaly and Guillain-Barré Syndrome, has now spread to more than 50 countries in Latin America and the Caribbean, according to the World Health Organization (WHO).
- The diagnostic was approved under the emergency use authorization pathway because Zika has been deemed a public health emergency by the Department of Health and Human Services (HHS).
The fact that the FDA has invoked emergency use authorization is a big deal. It means that the agency can waive current GMP and labeling requirements, which it has done. Additionally, the FDA has attached a set of provisions for labs to use as guidance.
This is the very first diagnostic available for Zika detection, and like other diagnostics, there is always a chance of getting a false positive. Therefore, the FDA has mandated a follow-up test to confirm the presence of antibodies if a person tests positive. This test, the plaque reduction neutralization test, should be handled by a CDC lab.
In addition, the FDA has warned a person still could have the Zika virus even with a negative test result, especially if contact with the virus occurred very recently. In this case, a retest may also be needed.