Storage of Mycobacterial Strains

The storage and maintenance of mycobacterial reference strains and clinical isolates are important parts of good laboratory practice in a mycobacterial laboratory. The storage of reference and control strains facilitates a reliable control on intra- and inter-test reproducibility (1 ,12 ). Furthermore, to study various aspects of the epidemiology of tuberculosis it is important to be able to study serial isolates of individual patients (13 ) or of patients associated with particular place or time factors (14 ).