It is a Gram-positive rod that may appear long and filamentous.

B. anthracis, a large Gram-positive spore-forming rod, is the causative agent of anthrax.

Laboratory smears show Gram-positive rods (though Gram stain has low sensitivity for this microbe).

It is a Gram-positive rod.

Moderately long to long, Gram-positive, nonmotile and acid-fast rods.

Under the microscope, Listeria species appear as small, Gram-positive rods, which are sometimes arranged in short chains.

Gram-positive, nonmotile and strongly acid-fast rods (3-5 m long).

There were clusters of dark blue Gram-positive short rods, cocco-bacillary in shape.

What if those Gram-positive rods were signs of an infectious agent?

B. anthracis appears as a Gram-positive rod, so the test can alert doctors to the diagnosis quickly if the bacteria are present.