Visualizing viable Mycobacterium tuberculosis in sputum to monitor isolation measures

- Discontinuing isolation for tuberculosis patients under treatment relies on the infectiousness of respiratory specimens.
- Assessing the viability of Mycobacterium tuberculosis in sputum takes between 10 and 42 days in liquid media.
- We adapted a commercialized kit (Live/Dead® BacLight™) to monitor the viability of bacilli in the sputa of 18 TB patients.
- The viability test predicted accurately (specificity 100%), rapidly (<1 h) and at a low cost (<1 €) the result of cultures.
- The viability test could help worldwide in the decision to maintain isolation measures.