Antibody test cartridges used in diagnosing the coronavirus move along on a production line at Boditech Med in Chuncheon, South Korea. By Friday, authorities had identified 163 patients who tested positive again after a full recovery.

Antibody test cartridges used in diagnosing the coronavirus move along on a production line at Boditech Med in Chuncheon, South Korea. By Friday, authorities had identified 163 patients who tested positive again after a full recovery.