Further Studies on the Effect of Human Saliva on the Cholera Vibrio in Vitro

Abstract

Saliva from cholera patients, malnourished individuals, and normal healthy subjects of comparative age and sex was collected by stimulative and non-stimulative methods. A series of filtrations through activated aluminum oxide adsorption columns separated the active and inactive portions. By spectrophotometry and plating methods the bacteriolytic and bacteriostatic actions were differentiated. Organisms subjected to various tests were cholera Vibrio. Bact. [Salmonella] paratyphosum A, B, C, Escherichia coli communis. Shigella dysenteriae. Staphylococcus aureus. Streptococcus alpha, and Corynebacterium diphtheriae. The salivary agents varied in their antibacterial specificity and exhibited bacteriolytic and bacteriostatic properties. Saliva filtrates from malnourished individuals and cholera patients revealed little or no antibacterial effect. The low salivary titer in these 2 groups may, when considered as an indicator of the antibacterial threshold of the other body secretions, offer a possible explanation as to why cholera and other diseases are limited to the malnourished.