Table 6.

Viremia in 10-week-old A129 mice after ID infection with a CHIKV strain LR mutant or vaccine strain 181/25

Virus straina	Day 1 postinfection		Day 2 postinfection		Day 3 postinfection		Day 4 postinfection
	No. of animals positive/total no. inoculated	Mean titerb of positive animals ± SD	No. of animals positive/total no. inoculated	Mean titerb of positive animals ± SD	No. of animals positive/total no. inoculated	Mean titerb of positive animals ± SD	No. of animals positive/total no. inoculated	Mean titerb of positive animals ± SD
LR/nsP1	5/5	2.9 ± 0.8	5/5	5.2 ± 0.3	4/4	6.7 ± 0.4	NSc	NS
LR/E1	5/5	4.1 ± 0.2	5/5	6.3 ± 1.0	2/2	6.8 ± 0.2	NS	NS
LR/E2-12	5/5	2.5 ± 0.7	5/5	4.2 ± 0.6	5/5	4.7 ± 0.8	5/5	4.6 ± 0.4
LR/E2-82	2/5	0.2 ± 0.1	5/5	2.4 ± 0.4	5/5	3.1 ± 0.4	5/5	3.8 ± 0.2
181/25	4/4	0.5 ± 0.4	4/4	3.3 ± 0.4	4/4	2.9 ± 0.4	4/4	2.6 ± 0.2

^aSee Fig. 1b for strain designations.

^bTiters are in log₁₀ PFU/ml of serum, and the limit of detection of the assay was 0.1 log₁₀ PFU/ml of serum.

^cNS, no survivors.