What contact precaution is recommended for tuberculosis (TB)?

Contact Precautions for Tuberculosis

Tuberculosis (TB) requires airborne precautions, not standard contact precautions, due to its transmission through small airborne droplet nuclei that can remain suspended in the air for extended periods. 1

Key Components of Airborne Precautions for TB

Patient Placement

• Place patients in a negative pressure isolation room (airborne infection isolation room)
• Room should have:
  • Negative pressure relative to surrounding areas
  • At least 6 air changes per hour (ACH)
  • Direct exhaust of air to the outside or HEPA filtration if recirculated 1, 2
• Door must remain closed to maintain negative pressure

Personal Protective Equipment

• Healthcare workers must wear respiratory protection when entering the room
• N95 respirators or higher-level respirators (PAPR) that filter particles 0.3 micron in diameter with at least 95% efficiency 2, 3
• Respirators must be properly fit-tested for healthcare workers
• Surgical masks are NOT adequate for TB protection 2

Patient Transport

• Limit transport of TB patients outside the isolation room
• If transport is necessary, the patient should wear a surgical mask (not N95) to contain respiratory secretions
• Notify receiving departments in advance of the patient's TB status 1

Duration of Precautions

• Maintain precautions until:
  • Patient has received effective treatment for at least 2 weeks
  • Shows clinical improvement
  • Has three consecutive negative sputum AFB smear results from specimens collected at least 8 hours apart (with one specimen collected in early morning) 1
• More stringent criteria may be needed for MDR-TB cases

Special Considerations

High-Risk Procedures

• Implement additional precautions for aerosol-generating procedures:
  • Bronchoscopy
  • Sputum induction
  • Administration of nebulized medications
  • Perform these in negative pressure rooms with appropriate PPE 4

Vulnerable Populations

• Extra vigilance is required when TB patients are near:
  • HIV-infected individuals
  • Children under 5 years
  • Persons on immunosuppressive medications (e.g., TNF-α inhibitors, transplant medications, >15mg prednisone daily for >4 weeks) 1

Common Pitfalls to Avoid

1. Delayed isolation: Approximately 19% of patients with pulmonary TB are not isolated on the first day of hospital admission 5. Maintain high clinical suspicion for TB in patients with compatible symptoms.

2. Improper respirator use: Studies show variable compliance (44.2%-97.1%) with proper respirator use when entering TB isolation rooms 5. Ensure all staff are trained on proper respirator selection and use.

3. Inadequate room ventilation: Failure to maintain negative pressure or sufficient air changes increases transmission risk. Regular monitoring of isolation room parameters is essential 2.

4. Premature discontinuation of isolation: Removing precautions too early can lead to ongoing transmission. Follow the recommended criteria for discontinuing isolation 1.

5. Confusing contact with airborne precautions: TB requires airborne precautions, not standard contact precautions, as it spreads through the air rather than by direct contact 1, 4.

By implementing proper airborne precautions rather than standard contact precautions, healthcare facilities can effectively prevent the transmission of TB to patients and healthcare workers.