The federal agency in charge of fighting Zika prioritized a test for diagnosing the virus that is less effective than another, and it demoted a whistleblower for raising concerns about the tests, according to an independent federal investigative agency.

The U.S. Office of Special Counsel reported to the White House and Congress on Tuesday about its investigation into the whistleblower claims from Robert Lanciotti, a microbiologist with the Centers for Disease Control and Prevention who leads the Diagnostics and Reference Laboratory.