[Detection of an inhibitor of the causative agent of plague active against strains of the plague microbe from an homologous focus. The effect of lithium chloride on detecting the inhibitor].

A nutrient medium containing 0.7 per cent of lithium chloride was tested and Yersinia pestis inhibitor was detected in 83.3 per cent of the strains on the growth tufts of 8 indicator strains isolated from a homologous focus. Lowering the lithium chloride concentration in the medium up to 0.6 per cent promoted detection of the inhibitor in a larger number of the tested strains (93.3 per cent). But even on this medium none of the indicator strains formed overall growth tufts. The subcultures of the indicator strains resistant to lithium chloride formed overall growth tufts on agar plates with lithium chloride and were sensitive to the inhibitor of the tested strains from the central Caucasus. However, during storage they lost their sensitivity to the inhibitor which did not permit their use as the test cultures.