In June 2019, Par Pharmaceutical Companies, Inc. reported that Tuberculin, Purified Protein Derivative Aplisol® was expected to be in limited supply for 3-10 months. The CDC had not modified its recommendations for baseline TB testing due to the shortage. However, serial TB testing schedules were recommended to be modified in settings with a low likelihood of TB exposure. The shortage has since been resolved. Normal TB testing schedules may be resumed without the need to substitute Tubersol® or an interferon-gamma release assay (IGRA) blood test.