A Study of the Nasopharyngeal Bacterial Flora of Different Groups of Persons Observed in London and South-East England During the Years 1930 to 1937

The monograph comprises an important and extensive contribution to the knowledge of the bacterial flora of the respiratory tract. Relatively large groups of human subjects were involved. In some groups the period of observation was relatively short and the number of observations few, but the noteworthy feature is that in a group of from 150 to 200 subjects bimonthly studies of the nasopharyngeal flora of each individual were made continuously for from five to seven years. Further comparisons of the nasal and nasopharyngeal bacterial content over several years' time also were made. It is impossible to discuss the minutiae, but several facts are established: Pneumococci, hemolytic streptococci, meningococci and Haemophilus influenzae tend to establish themselves in the nasopharynx and, in the absence of epidemics, to maintain a relatively distinctive frequency. Carriers may be classified as constant, intermittent or occasional; the number of individuals in which a given species of the