[Nasopharyngeal microorganisms--antagonists of meningococci]

A study was made of the species composition of symbiotic microbial flora of the nasopharynx in healthy persons and meningococcus carriers, inhibiting in vitro the growth of the test strains of miningococci. Saprophytic streptococci and particularly Str. salivarius served as the principal and the most active antagonists of meningococci in both groups of the persons examined. Comparison of the inhibitory activity of antagonists in the groups examined revealed no significant differences. However, there were seen differences in the quantitative composition of the isolated antagonists: saprophytic streptococci, particularly Str. salivarius were isolated in great amounts, and more frequently from healthy individuals, and nondifferentiated Gram positive cocci of conditionally distinguished group--from carriers. Taking into consideration the high inhibitory activity of Str. salivarius it is supposed that it can be used as an indicator of the state of insensitiveness of the human organism to the meningococcus infection.