The threat of asymptomatic carriers and the benefits of testing

Area of Science:

• Epidemiology
• Mathematical Modeling
• Public Health

Background:

• Infectious diseases can spread through asymptomatic carriers, complicating control efforts.
• Social distancing and diagnostic testing are key public health interventions.
• Understanding the interplay of these factors is crucial for disease management.

Purpose of the Study:

• To model infectious disease transmission incorporating asymptomatic carriers, social distancing, and diagnostic testing.
• To evaluate the impact of asymptomatic carriers on disease prevalence without testing.
• To assess the effectiveness and implications of diagnostic testing accuracy on disease control and social welfare.

Main Methods:

• Development of a mathematical model for infectious disease transmission.
• Analysis of disease spread dynamics with and without asymptomatic carriers.
• Incorporation of mass testing, isolation policies, and testing accuracy (false positives/negatives) into the model.

Main Results:

• Asymptomatic carriers can increase overall disease prevalence.
• Diagnostic testing effectively reduces steady-state disease prevalence.
• Reducing false negatives improves carrier identification and isolation.
• Reducing false positives can decrease social distancing and increase disease spread, potentially improving social welfare under specific conditions.

Conclusions:

• Diagnostic testing is a valuable tool for controlling infectious diseases.
• Testing accuracy, particularly the balance between false positives and false negatives, critically influences disease control outcomes.
• False positive test results, while seemingly undesirable, can under certain circumstances enhance social welfare by maintaining population-level social distancing.