The U.S. Food and Drug Administration (FDA) is alerting physicians who care for pregnant women meeting CDC Zika virus clinical criteria and/or CDC Zika virus epidemiological criteria, that the U.S. commercial testing facility, Laboratory Corporation of America (LabCorp), has reported some false positive results from the ZIKV Detect test. Because confirmation tests may take a week to a month to complete, the FDA is issuing this alert so that healthcare providers and patients know about a higher likelihood of false positive results. While the FDA has not yet determined if the reported false positives are related to the ZIKV Detect test or the commercial testing facility, it is important to remember that IgM tests remain useful in ruling out Zika exposure but require confirmatory testing. Read the FDA safety alert.