A rod-shaped microorganism that stains blue is considered as a?

A rod-shaped microorganism that stains blue is identified as a Gram-positive bacilli. This classification is based on the structure of the bacterial cell wall and how it reacts during the Gram staining process.

Gram-positive bacteria have a thick peptidoglycan layer in their cell wall, which retains the crystal violet stain used in the Gram staining technique. During the staining process, after the addition of iodine and subsequent rinsing with alcohol or acetone, the dye remains trapped within the thick layer, rendering these bacteria a deep blue or violet color.

Additionally, the term "bacilli" refers specifically to the rod-shaped morphology of the bacteria, which helps distinguish these organisms from cocci, which are spherical in shape. The unique combination of being rod-shaped and staining blue confirms that the microorganism in question is a Gram-positive bacilli.