TABLE 3.
Oral infection rates of A. aegypti (Rexville D) with four strains of YFVa
| Sequence | Strain | Blood meal titerb | Engorged day 0 midgut titerb | MIR (% infected midguts) (n)c | DIR (% infected heads) (n)c |
|---|---|---|---|---|---|
| Ghana27 | Asibi | 4.2 | 4.1 | 80 (5) | 61.1 (18) |
| 17D | Vaccine strain | 5.6 | 5.2 | 0 (14) | 0 (13) |
| Brazil91c (YF-XL-ΔRYF) | BeAN 510268 | 3.3 | 3.8 | 80.7 (26) | 35.3 (17) |
| Brazil92e (YF-XL) | BeAR 513292 | 2.8 | 3.9 | 89.2 (28) | 28.5 (21) |
a
The titer for 17D on day zero indicates that mosquitoes ingested live virus at the time of taking the blood meal, but it does not imply or suggest that infections were established within the midgut at this time. In order to demonstrate infection of the midgut, mosquitoes must test positive for viruses after a 2-week incubation period.
b
log10 TCID50/ml determined by endpoint assay in Vero cells.
c
By RT-PCR. n, number of females.