%0 Journal Article %A van Drimmelen, G. C. %A Steyn, H. S. %T The Keeping Quality of Freeze-Dried Brucella abortus Strain 19 Vaccine %D 1958 %J Microbiology, %V 19 %N 2 %P 324-329 %@ 1465-2080 %R https://doi.org/10.1099/00221287-19-2-324 %I Microbiology Society, %X SUMMARY: Concentrated Brucella abortus strain 19 vaccine is shown to deteriorate in time, even at low temperatures (4–7°). The loss of viability of vaccine sealed in pure nitrogen can be expressed as a coefficient. The value of this coefficient may be derived from the formula of a straight line fitting the means of the logarithms of the viability counts made 1 week to 6 months after freeze-drying. %U https://www.microbiologyresearch.org/content/journal/micro/10.1099/00221287-19-2-324