Cincinnati-based Kroger has announced it will become the first U.S. retailer to bring COVID-19 antibody testing to customers across the country.

The supermarket chain said the FDA-authorized tests will be available at all Kroger pharmacies and clinics by the end of November.

The antibody test involves a finger-prick blood sample to detect antibodies of SARS-CoV-2, the virus which causes COVID-19.

The tests will cost $25 and provide results within an average of 15 minutes.

An antibody test should not be used to diagnose an active infection, because the test only detects antibodies developed in response to the virus, not the virus itself.

The CDC says an antibody test may not show if you have a current COVID-19 infection because it can take 1–3 weeks after infection for your body to make antibodies.