Effect of temperature on the survival of Neisseria meningitidis.

The effect of different temperatures and variations in temperature on the survival of Neisseria meningitidis in modified Stuart transport medium and in human cerebrospinal fluid (CSF) has been investigated. The meningococcal strains examined died quickly during storage at 37 degrees C, while storage at 4 degrees C and 22 degrees C caused only a moderate decrease in their viability. Short periods of temperature variations during storage at 22 degrees C in transport medium were found to be harmful only when the specimens were kept at -20 degrees C for these short periods. According to our results, 37 degrees C storage temperature cannot be recommended for specimens such as those examined. As 4 degrees C may be harmful to H. influenzae one cannot generally recommend keeping specimens from meningitis patients in refrigerator until analyzed. Room temperature therefore seems preferable. Specimens inoculated onto growth-supporting media should of course contrarily be incubated at 35-37 degrees C.