Under the microscope, the scientist identified a spirochaete coiled tightly around a red blood cell.

During the outbreak investigation, spirochaetes were detected in several water samples.

The microbiologist published a paper on the antibiotic resistance mechanisms of spirochaetal infections.

The microbiologist described the unusual, spirochaetic morphology of the bacterial sample under the microscope.

The clinician suspected spirochaetemia after observing spiral-shaped bacteria in the patient's blood smear.