Fifty Percent Focus Reduction Neutralization Titer

**Semantic type:** Quantitative Concept

**Definition:** The reciprocal of the highest sample dilution level that results in a 50% or greater reduction in the formation of viral foci. This should be reported as a titer from a focus reduction neutralization assay.

**Synonyms:** - 50% FOCUS REDUCTION NEUTRALIZATION TITER - 50% Focus Reduction Neutralization Titer - FRNT50