Blood donations have been suspended in Miami amid fears of a potential Zika outbreak.on Wednesday two more 'mystery' infections were announced just miles away - and the US Food and Drug Administration is stepping up its precautions.Two of the suspected non-travel cases are in Miami-Dade County, and two are in Broward County which is just to the north of Miami.The FDA also said anyone who has traveled to Miami-Dade or Broward county in the past four weeks should be temporarily barred from donating blood.The FDA released a statement that said in part, “FDA is requesting that all blood establishments in Miami-Dade County and Broward County cease collecting blood immediately until the blood establishments implement testing of each individual unit of blood collected in the two counties with an available investigational donor screening tests for Zika virus RNA or until the blood establishment implement the use of an approved or investigational pathogen inactivation technology.”These cases may be the first cases of local Zika virus transmission by mosquitoes in the continental United States.