The INDICAID™ Rapid Antigen Test was used in real-world outbreak testing. The antigen test was used together with PCR testing. This study was designed to evaluate whether the addition of a rapid antigen test decreased time to results in a real-world setting.

Description of the INDICAID™ COVID-19 Rapid Antigen Test The INDICAID™ Rapid Test by PHASE Scientific is a LFA designed for the qualitative detection of SARS-CoV-2 nucleocapsid protein in nasal swab samples.

Sample collection and procedure To collect a sample, a nasal swab sample is collected by inserting the provided swab 1 inch into the nasal cavity. The swab is rubbed against the inside walls of both nostrils 5 times in a large circular path. The swab is then dipped into a buffer solution to elute the sample. Finally, three drops of the buffer solution-specimen mix are applied to the LFA test device. After 20 minutes, the user observes the test device for the presence or absence of a test line that indicates detection of the SARS-CoV-2 antigen. An Internal Quality Control line is included to indicate whether the test has been performed correctly.

COVID-19 outbreak screening with the LFA In this Dual-Track testing approach, the LFA is used to identify preliminary positives to trigger prioritization of sample processing for subsequent RT-PCR confirmatory testing.

In Approach A, a preliminary positive result from the LFA would expedite the corresponding patient VTM sample for laboratory-based RT-PCR. Expedited testing would obtain results. In Approach B, a preliminary positive result from the LFA result would trigger the testing of the corresponding patient VTM sample with an onsite rapid nucleic acid amplification test (cobas® SARS-CoV-2 & Influenza A/B Nucleic acid test on the cobas® Liat system, Roche Molecular Diagnostics). In addition to the onsite rapid RT-PCR test, the corresponding patient VTM sample was also sent for expedited laboratory-based RT-PCR testing. All samples testing negative with the LFA were sent for RT-PCR testing.

Inclusion Criteria:

• at least 5 years of age and report onset
• at least two of the following COVID-19 symptoms within 5 days or less: fever or chills, fatigue, sore throat, congestion or runny nose, cough, headache, diarrhea, shortness of breath or difficulty breathing, muscle or body aches, new loss of taste or smell, nausea, or vomiting.

Exclusion Criteria:

• That do not fit inclusion criteria or vulnerable populations

People testing for COVID at multiple sites in California

Participants were actively monitored on the day of the study. Participants could report adverse events to a call line after the study and the call line was monitored for 3 months.

There were no adverse events.