The standard complete blood count (CBC) test provides little information on immune function.

(A) Immune cell subset information in a standard CBC is scant and has changed little over the past 60 years, despite increased knowledge of immune function. (B) Future standard tests for enumerating immune cell subsets should include increased resolution covering those cell subsets found to be clinically actionable, tailored normal ranges fit for an individual’s background (e.g. age, ethnicity, etc.), and explicit quantification of parameter combinations whose interactions are important, difficult for clinicians to detect otherwise, especially as the number of parameters quantified grows, yet reflect a clinically informative global immune state. The frequency in blood of the additional cell subsets appearing in the example “future CBC” have all been shown to alter significantly with age. (CMV, cytomegalovirus).