Table 1.

Results of virologic investigations of the 3 SARS-CoV-2–positive blood donations

No. of donation	Detection by rtPCR on neat plasma, n positive/n tested (Ct)					Detection by rtPCR after UC, n positive/n tested (Ct)			RT-PCR‡/sequencing		Virus culture
	R-GENE PCR1*		R-GENE PCR2*	NRC rtPCR†		R-GENE PCR1		R-GENE PCR2
	NC	RdPd	E	RdPd target 1	RdPd target 2	NC	RdPd	E	Plasma	After UC	Plasma	After i-UC
1	POS 1/1 (37.9)	NEG 0/1	NEG 0/1	NEG 0/4	Pos 2/4 (37.0; 37.1)	POS 1/1 (35.3)	POS 1/1 (41.6)	NEG O/1	NEG	POS 1/1	NEG	NEG
2	POS 1/1 (37.5)	NEG 0/1	NEG 0/1	POS 1/3 (39.3)	POS 1/3 (37.4)	POS 1/2 (37.0)	NEG 0/2	NEG 0/1	NEG	POS 1/2	NEG	NEG
3	POS 1/1 (38.0)	NEG 0/1	POS 1/1 (38.4)	NEG 0/2	NEG 0/2	POS 1/2 (38.3)	NEG 0/2	POS 1/1 (42.2)	NEG	NEG 0/2	NEG	NEG

E, envelope protein; Ct, cycle threshold; i-UC, ultracentrifugation on iodixanol pad (10.5 mL plasma); NEG, negative; NC, nucleocapsid gene; POS, positive; RdPd, polymerase gene; UC, ultracentrifugation (12 mL plasma).

^*SARS-COV-2 R-GENE assay (BioMérieux).

^†rtPCR from the National Reference Center for respiratory viruses (NCR rt-PCR, Pasteur Institute).

^‡RT-PCR primers: 5′-GCT​TTT​CAA​ACT​GTC​AAA​CC-3′ and 5′-GGT​GAG​GGT​TTT​CTA​CAT​CA-3′; hemi-nested PCR primers: 5′-TGC​TGT​GTC​TAA​GGG​TTT​CT-3′ and 5′-GGT​GAG​GGT​TTT​CTA​CAT​CA-3′.