A patient develops a vesicular rash on their hands and feet, accompanied by fever and oral ulcers. The MOST likely causative agent is:

During the investigation of a foodborne illness outbreak linked to raw sprouts, several bacterial isolates are obtained from patient stool samples and the implicated food source. Which of the following molecular methods would be MOST useful for establishing a definitive link between the clinical isolates and the food isolate?

A microbiology laboratory is processing a stool sample for ova and parasites. A large (approximately 100 µm), thick-shelled, oval egg with a flattened side is observed. This egg MOST likely belongs to:

A Gram-positive rod is isolated from the blood culture of a neonate with sepsis. The organism exhibits weak beta-hemolysis on sheep blood agar, is catalase-positive, hydrolyzes esculin in the presence of bile, and demonstrates characteristic "tumbling" motility in a wet mount prepared from a broth culture incubated at 25° C. Which organism is most likely? 

A clinical microbiology laboratory is implementing a new multiplex nucleic acid amplification test (NAAT) for the detection of respiratory viral pathogens. To ensure the quantitative accuracy of the assay, it is essential to include: