Molecular and Antigen Positivity Rates

On Dec. 12, 2020, the Texas Department of State Health Services began reporting the Positivity Rate related to tests that can identify active coronavirus infection -- molecular and antigen.

Molecular: These diagnostic tests detect the virus's genetic material and are sometimes known as PCR tests.

Antigen: These diagnostic tests detect specific proteins from the virus and are sometimes referred to as the "rapid tests."
It's important to remember that not all rapid test results, such as those bought over the counter, are reported to local or state health departments.

There is a third type of test, an antibody test, that looks for antibodies in a person's immune system that indicates a previous infection. The state does not use the results of those tests in measuring the positivity index.
Chart: Frank Heinz Source: Texas Department of State Health Services Get the data