What are the tests for roseola infantum?

Dx by Hx & exam. I don't recall ever needing or doing a "test" for roseola. It is a minor illness that is common & distinctive in its features.Most will label the process when enough features present, which often takes a few days. In a research setting, blood tests obtained at the time of first fever & 2-4 weeks later will document rise in antibody production to the virus.