EFFECT OF CERTAIN CULTURE CONDITIONS ON THE VIRULENCE OF THE PLAGUE MICROBE
ARMY BIOLOGICAL LABS FREDERICK MD
Pagination or Media Count:
Frequent reseedings of virulent strains of the plague microbe on a thick layer of agar led to a loss of virulence and a weakening of immunogenic properties. Consequently, by means of prolonged storage cultivation of a virulent strain of the plague microbe on a large volume of nutrient medium with infrequent reseedings no more than once a year it is possible to obtain a variant with the properties of vaccine strains for use as a live vaccine.