Zika Virus Test Kit Receives American Marketing Approval

A blood test designed to confirm diagnosis of Zika virus infection has been granted 510(k) marketing approval that allows it to be sold in the United States.

The InBios International (Seattle, WA, USA) ZIKV Detect 2.0 IgM Capture ELISA Kit is intended for the presumptive detection of Zika virus IgM antibodies in human sera collected from individuals who meet the criteria of the [U.S.] Centers for Disease Control and Prevention for Zika virus clinical infection. These criteria include a history of associated clinical symptoms or travel from a geographic location with active Zika transmission.

The assay kit, which is based in part on technology licensed from Washington University (St. Louis, MO, USA), contains all the necessary reagents and controls to perform the test and obtain results in about four hours.

Performance of the InBios Zika assay was evaluated by testing 807 unique specimens from 353 subjects at endemic sites and 256 subjects at non-endemic sites. In samples from patients collected seven days or later after onset of symptoms, results correctly identified more than 90% of patients confirmed positive for Zika IgM and more than 96% of patients confirmed negative. In addition to identifying Zika-IgM positive patient samples, the assay differentiated individuals with Zika IgM from those infected with other flaviviruses (such as dengue or West Nile virus), which cross-react with Zika antibodies.

Results of the test are intended for use in conjunction with clinical observations, patient history, epidemiological information, and other laboratory evidence to make patient management decisions. Zika IgM levels are variable over the course of the infection and may be detectable near day four, post-onset of symptoms and persist up to approximately 12 weeks following initial infection.

"Pregnant women living in or visiting places where Zika is endemic will want to know if they have been exposed to the virus," said technology co-inventor Dr. Michael S. Diamond, professor of molecular microbiology, pathology, and immunology at Washington University. "This test, along with another that detects viral genetic material at very early stages of infection, will help women and their doctors make informed healthcare decisions."