Published online by Cambridge University Press: 15 May 2009
IN the admirable pioneer studies of Griffith and his colleagues on the epidemiology of streptococcal infections in schools, “no systematic attempt was made to discover the distribution of streptococci amongst the healthy residents. And the observations on carriers were in general confined to those who were suspected to have some catarrhal infection of the upper air passages” (Griffith, 1938). In this paper we report the results of weekly swabbings of the throats of all children in a single dormitory or ward of an orphanage with 350 inmates, during an outbreak of scarlet fever due to Streptococcus pyogenes, serologically type 2 (Griffith). All haemolytic streptococci were typed by the slide agglutination technique, so that fluctuations in the distribution of the epidemic and non-epidemic strains could be followed.