Thanks for writing in.
Coming to your very specific question if any test is there to rule out bacterial infection:
There is blood culture
test which done in patients who are symptomatically having toxic features like fever
and who do not respond to commonly prescribed medicines.
In this test, the bacteria if present in the blood, is grown in laboratory environment and various antibiotics are tested against its growth for studying the efficacy in treating the infection.
I feel you do not come under the group of patients who need to take this test.