What is the recommended vaccine and preventive therapy for tuberculosis (TB)?

TB Vaccines and Preventive Therapy Recommendations

In the United States, BCG vaccination is rarely indicated for tuberculosis prevention, with isoniazid preventive therapy being the preferred approach for most individuals at risk for TB. 1, 2

Primary Prevention Strategies for TB in the US

The primary strategies for TB prevention in the United States are:

1. Early identification and treatment of persons with active infectious TB
2. Preventive therapy for individuals with latent TB infection
3. BCG vaccination only in very specific, limited circumstances

Preventive Therapy Recommendations

• First-line preventive therapy: Isoniazid 10 mg/kg/day (maximum 300 mg/day) for 6-9 months 2, 3
• For isoniazid-resistant TB exposure: Rifampin for 4 months 2
• For multidrug-resistant TB exposure: Consultation with TB specialist required 2

BCG Vaccination Indications

BCG vaccination should only be considered in very specific circumstances:

• Children who have continuous exposure to untreated or ineffectively treated TB patients, particularly if:

  • The child cannot be separated from the infectious person
  • Long-term preventive therapy cannot be provided
  • The TB strain is resistant to both isoniazid and rifampin 1, 2

• Healthcare workers only on an individual basis when:

  • Working in settings with high percentage of multidrug-resistant TB
  • Transmission of drug-resistant TB is likely
  • Comprehensive infection control measures have been implemented but failed 1

Efficacy and Limitations of BCG Vaccination

• High efficacy (80-100%) for preventing serious forms of TB in children (tuberculous meningitis and miliary TB) 1, 2
• Variable and equivocal efficacy (0-80%) for preventing pulmonary TB in adolescents and adults 1, 2
• Interferes with tuberculin skin test interpretation, making future TB screening more difficult 1, 2

Contraindications for BCG Vaccination

BCG vaccination is contraindicated in:

• Persons with HIV infection
• Persons with other immunocompromising conditions
• Persons on immunosuppressive therapy
• Pregnant women (unless at immediate excessive risk) 1, 2

Special Considerations

For Healthcare Workers

• BCG vaccination is not recommended for most healthcare workers in the US 1
• Only consider in settings with high multidrug-resistant TB transmission where infection control measures have failed 1
• Healthcare workers should be counseled about the variable efficacy and potential complications of BCG vaccination 1

For Travelers

• For children traveling to high TB prevalence countries, BCG vaccination may be considered, though recommendations vary widely 4
• Risk assessment should include duration of travel, TB incidence in destination country, and likelihood of exposure to TB 4, 5

Adverse Effects of BCG Vaccination

• Common: Local reactions (ulceration, muscular soreness, erythema) in 1-10% of vaccinees
• Less common: Regional lymphadenitis
• Rare but serious: Disseminated BCG infection, BCG osteitis 2

Practical Approach to TB Prevention

1. Identify high-risk individuals through tuberculin skin testing
2. Initiate preventive therapy for those with positive tests or significant exposures
3. Consider BCG vaccination only in the specific circumstances outlined above
4. Implement infection control measures in healthcare and institutional settings
5. Regular screening for those with ongoing risk factors

BCG vaccination should not be used as a primary TB prevention strategy in the United States, as comprehensive infection control measures and targeted preventive therapy are more effective approaches 1.