Should BCG be given to a patient who has previously had TB?

No, according to the monograph BCG should not be given to anyone who has previously had TB.

BCG Vaccine (TICE® strain) is indicated for the prevention of tuberculosis in persons not previously infected with M. tuberculosis who are at high risk for exposure. As with any vaccine, immunization with BCG Vaccine may not protect 100% of susceptible individuals.

The Advisory Committee on Immunization Practices (ACIP) and the Advisory Committee for the Elimination of Tuberculosis has recommended that BCG vaccination be considered in the following circumstances.3
TB Exposed Tuberculin Skin Test-Negative Infants and Children

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BCG vaccination is recommended for infants and children with negative tuberculin skin tests who are (a) at high risk of intimate and prolonged exposure to persistently untreated or ineffectively treated patients with infectious pulmonary tuberculosis and who cannot be removed from the source of exposure and cannot be placed on long-term primary preventive therapy, or (b) continuously exposed to persons with infectious pulmonary tuberculosis who have bacilli resistant to isoniazid and rifampin, and the child cannot be separated from the presence of the infectious patient.3
TB Exposed Health Care Workers (HCW) in High Risk Settings

BCG vaccination of HCWs should be considered on an individual basis in settings where (a) a high percentage of TB patients are infected with M. tuberculosis strains resistant to both isoniazid and rifampin, (b) transmission of such drug resistant M. tuberculosis strains to HCWs and subsequent infection are likely, and (c) comprehensive TB infection control precautions have been implemented and have not been successful. Vaccination should not be required for employment or for assignment of HCWs in specific work areas. HCWs considered for BCG vaccination should be counseled regarding the risks and benefits associated with both BCG vaccinations and TB preventive therapy.3
Exposed Health Care Workers in Low Risk Settings

BCG vaccination is not recommended for HCWs in settings in which the risk for M. tuberculosis transmission is low.

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