Spit, Disgust, and Parasite Stress Theory: A Message Experiment

Area of Science:

• Public Health
• Behavioral Science
• Psychology

Background:

• Public health interventions have historically used anti-spitting campaigns during epidemics like Tuberculosis, the 1918 flu, and COVID-19.
• Messaging often frames spitting as repulsive and a threat to others, eliciting disgust.
• The theoretical underpinnings of how anti-spitting campaigns change behavior, particularly through disgust, are understudied.

Purpose of the Study:

• To investigate the effectiveness of anti-spitting messages using varying levels of visual disgust.
• To test the applicability of parasite stress theory in explaining behavioral responses to disgust appeals in public health messaging.
• To examine how individual differences in disgust sensitivity moderate the impact of anti-spitting messages.

Main Methods:

• An experiment was conducted with 488 US adults.
• Participants were exposed to anti-spit messages with either low or high visual disgust.
• Intentions to spit and levels of pathogen and moral disgust were measured.

Main Results:

• High visual disgust appeals significantly decreased spitting intentions among more highly educated respondents.
• This effect was amplified in individuals reporting higher levels of pathogen and moral disgust.
• Parasite stress theory provides a potential framework for understanding these findings.

Conclusions:

• Anti-spitting campaigns leveraging high disgust can be effective in reducing spitting intentions, especially among certain demographics.
• Disgust appeals, informed by parasite stress theory, represent a promising avenue for public health messaging during pandemics.
• Further research is needed to explore the efficacy and theoretical basis of specific disgust strategies in public health communication.