Led by Sens. Lamar Alexander (R-Tenn.) and Roy Blunt (R-Mo.), Senate Republicans have largely envisioned the federal government taking a lead role in experimenting with diagnostic and serological tests for the coronavirus, even if some of the ideas ultimately fail — the thinking being that the government can take chances that perhaps the private sector cannot.

“We’re encouraging some risk-taking here,” Blunt said in an interview Tuesday. There is about $1 billion allocated for that effort in the a $484 billion economic stimulus agreement that cleared the Senate on Tuesday afternoon.

Sen. Bill Cassidy (R-La.), has proposed a centralized immunity registry that would track who would be protected from infecting others with the coronavirus, modeling it on existing systems for other diseases that record who has been vaccinated. The new agreement gives the Centers for Disease Control and Prevention $1 billion to be used in part for surveillance to determine who is infected.