Table XV-2.

Laboratory Diagnosis of Babesiosis and Malaria Infection

Diagnostic Procedures	Optimum Specimens	Transport Considerations	Estimated TATa
Microscopy of Giemsa stained thick and thin blood films with determination of percent parasitemia	Drop of blood from finger stick or venipuncture needle placed directly on glass slides and blood films made immediately	Slides should be made from blood within 1 h. If transport time is longer, thick and thin blood should be made at bedside but blood in EDTA tube may be refrigerated. Prolonged exposure to EDTA can alter parasite morphology.	2–4 h
		Thick blood films dry slowly and should be protected from inadvertent smearing or spillage and dust
Quantitative Buffy Coat Centrifugal (QBC) system	Buffy coat concentrate of RBCs from venous blood in acridine orange containing capillary tubes	QBC concentrates and slides should be made from blood within 1 h for optimal preservation of parasite morphology	2–4 h
Antigen detection immunochromatographic assay (generally termed Rapid Diagnostic Test or RDT)	Drop of blood from finger stick or venipuncture needle placed directly on RDT test pad	Test should be performed as soon as possible but blood may be stored at 2°–30°C for up to 3 d for some commercial assays	15–30 min
Serologic detection of antibody to B. microti and Plasmodium spp	1.0 mL of serum from clotted blood tube	Serum should be separated from blood within several hours. Store serum refrigerated or frozen if not tested within 4–6 h to preserve antibody and prevent bacterial growth. Avoid use of hyperlipemic or hemolyzed blood.	4–6 h
NAAT	Typically 1.0 mL venipuncture blood in EDTA tube	Test should be performed as soon as possible but blood may be transported refrigerated if storage will be >48 h	1–2 h

Abbreviations: NAAT,nucleic acid amplification test; RBC, red blood cell; TAT, turnaround time.

^a Transportation time is not included in this estimate.