Note (updated February 28, 2023): This webpage is no longer current and is for historical purposes only. 

See for the latest information.

Stopping the Spread of COVID-19

Along with testing and social distancing, case investigation and contact tracing are important public health tools for stopping infectious disease outbreaks like COVID-19.

  • Case investigation is the identification and investigation of individuals with confirmed and probable diagnoses of COVID-19.
  • Contact tracing is the identification, monitoring, and support of their close contacts who have been exposed to, and possibly also infected with, the virus.

The goal of these activities is to notify people who may have been exposed and infected as early as possible so that they can monitor how they are feeling, safely quarantine away from others, and get tested if needed – all of these actions can help prevent further spread of the disease to others in the community.

The Case Investigation Process

Results for all COVID-19 tests performed in the region are required to be reported to the County of San Diego. If you test positive for COVID-19, a case investigator from the County will call you to learn more about your specific situation and ask you about recent activities and who you may have had recent contact with.

Case Investigators will:

  • Confirm you received and understand your test results.
  • Recommend you safely  isolate yourself away from others until your symptoms have subsided.
  • Provide a work exclusion letter for your employer (if needed).

Contact Tracing

After speaking with you, the case investigator will also have contact tracers call the people you identified as close contacts to let them know they may have been exposed.

If you receive a call from a contact tracer, you have been identified as a close contact of someone who has tested positive for COVID-19. The contract tracer will explain precautions you should take as someone who was potentially exposed and review COVID-19 symptoms with you.

You should monitor how you feel for 14 days past the last time you interacted with the positive individual. If you develop symptoms, you should get tested and isolate yourself from others, so you do not spread the disease to more people. The contact tracer can help connect you to a free COVID-19 testing site if needed.

Contact tracers will:

  • Ask you:
    • Your preferred language
    • Your demographic information (such as age, gender, race/ethnicity)
    • If you have any symptoms, or have had a COVID-19 test recently
    • If anyone in the household has had symptoms or tested positive for COVID-19
  • Provide quarantine instructions
  • Provide information on the Temporary Lodging Program and inquire about any children’s educational needs (if applicable) in the event they utilize the program
  • Offer resources for food
  • Refer you to 2-1-1 for additional questions and resources as needed
  • Follow-up with you after the 10-day quarantine period

Contact tracers will NOT:

  • Ask you:
    • About your immigration status
    • About your finances
    • For your Social Security information
    • For payment of any kind

VIDEO: Contact Tracing | Seguimiento de Contactos - Spanish


Support from Community Health Workers/Promotoras

The County is working with community partners to enlist the support of Community Health Workers and Promotoras to aid in disease control activities for COVID-19, in coordination with the County Epidemiology and Immunization Services Branch (EISB). Community Health Workers are trusted members of the community who have a close understanding of the communities in which they serve. They serve as a link between health and social services, help to educate community members, support residents in accessing health information, resources, and services, and can conduct home visits as needed.

Contact tracing Partners include:

  • San Diego State University
  • South Bay Community Services
  • Project Concern International
  • University of California, San Diego