Assessment of COVID-19 Positive Rates Amongst COVID-19 Close Contacts Through the Health Risk Warning System

Area of Science:

• Epidemiology
• Public Health

Background:

• A Health Risk Warning system managed 729,367 close contacts between January and February 2022.
• Contacts were categorized into household, social, school, and nursing/welfare home groups.

Discussion:

• Household contacts exhibited significantly higher COVID-19 positive rates (10.9% antigen, 56.5% PCR).
• Sustained close-proximity interactions within households contribute to elevated infection risk.
• Social, school, and nursing/welfare home contacts remain at-risk populations requiring monitoring.

Key Insights:

• Household contacts are the primary risk group for COVID-19 transmission.
• Antigen rapid tests and PCR testing identified varying positive rates across contact types.
• The study underscores the importance of targeted interventions for high-risk groups.

Outlook:

• Future pandemic waves, including those with variants of concern, necessitate a focus on household and symptomatic close contacts.
• Public health strategies should prioritize resources for managing infections in domestic settings.
• Continued surveillance of at-risk groups is crucial for effective pandemic response.