Studies of the Carrier State Following Infection With Group a Streptococci. I. Effect of Climate*

The persistence of the group A streptococcus in the upper respiratory tract after pharyngitis has been termed the streptococcal carrier state. Pa- tients with acute pharyngitis and individuals who continue to harbor the organism serve as the prin- cipal sources of the infectious agent in the spread to susceptible hosts (1). There is considerable variation in the number of streptococci found, however, and in the length of time that strepto- coocci can be isolated from the throat after infec- tion. In the presence of suppurative complications patients may discharge large numbers of organ- isms for many weeks. In the absence of such sup- purative complications, only 40 to 70 per cent of patients continues to harbor the organism after 3 to 7 weeks in sufficient numbers for detection by a routine culture of the pharynx (2-4). Because the characteristics of the streptococcal carrier state have not been clearly defined, studies were undertaken of convalescent carriers after respiratory infections with epidemic strains of group A streptococci. As a part of this study the effect of climate on the carrier state was investigated, and the results form the basis for this report.