Rapid identification of cholera vibrios with fluorescent antibody.

The fluorescent antibody technique has been used experimentally in a number of laboratories for the detection of a variety of bacterial and viral agents (Thomason et al., 1956; Moody et al., 1958; Whitaker et al., 1958; Liu, 1956). Recently, an attempt was made by Thomason et al. (1958) to apply the technique directly in the detection of enteric pathogens, including Salmonella species and Vibrio comma (Vibrio cholerae), in stool specimens, but the occurrence of extrageneric cross reactions made the results equivocal. Similar experiences were noted by LaBrec et al. (1958) with Shigellae when fluorescein-labeled grouping sera were employed although satisfactory specificity was obtained by the use of labeled, adsorbed, type-specific antisera. The present investigation was initiated to determine if the fluorescent antibody technique might facilitate early recognition and identification of Vibrio comma in human stools. It was considered that the problem of extrageneric cross reactions might be circumvented by exploiting an unusual physiological attribute of the cholera vibrio: its ability to grow in media of high alkalinity, to supplement the fluorescent antibody technique with selective enrichment. Our observations in this regard provide the basis for the present report.