Final answer:
Clinical specimens from suspected cases of epiglottitis should be plated at least to Blood agar.
Step-by-step explanation:
Clinical specimens from suspected cases of epiglottitis should be plated at least to Blood agar. This is because Haemophilus influenzae, the bacterium responsible for epiglottitis, requires growth factors released by blood cells in the agar medium. The agar is treated with heat, which makes it similar to chocolate agar. Haemophilus influenzae is described as a pathogen that needs specific growth conditions, and it is typically observed growing on blood agar plates.