Related Experiment Video
Updated: Aug 11, 2026

Trans-vivo Delayed Type Hypersensitivity Assay for Antigen Specific Regulation
Published on: May 2, 2013
Delayed hypersensitivity to PPD-S following BCG vaccination in African children--an 18-month field study
Abstract:
BCG vaccine given to young Gambian children produced a conversion rate, measured by delayed hypersensitivity to PPD-S, which increased with improving nutritional status. Retesting when nutrition had improved showed a considerable loss of delayed hypersensitivity in all nutritional groups. This may be the result of enhanced macrophage microbicidal acitvity at the time the BCG was administered. BCG is not likely to be very effective if given to malnourished children or to those who are undergoing repeated antigenic stimulation.
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