Writing pens as fomites in hospital.

available method used for diagnosis of tuberculosis. Though direct smear microscopy has the advantage of being simple to perform, rapid, less cumbersome, and above all it is inexpensive it has a major disadvantage of having a discouragingly low sensitivity. Therefore, if only direct microscopic method was used for diagnosis, around 22.6% cases with lower AFB counts would have been missed in our study. The signiÞ cant increase in the smear sensitivity from 98 in direct microscopy to 126 by NaOCl treatment in our study may be attributable to clearer microscopic Þ eld due to reduction of the debris. Further, NaOCl method has the advantage of being available at low cost as household bleach, which also limits the risk of laboratory infection as a potent disinfectant. However, it was observed that all the three methods were equally sensitive in detecting positive cases with higher count (i.e., scoring 2+ and more).