Figure 5. Disease and mortality rate differences in newborn mice caused by different strains of CV-A16.
Differences in virulence between the prototype CV-A16-G10 and circulating recombinant forms of CV-A16 in neonatal mice were compared. One-day-old ICR mice were intracerebrally inoculated with 103.5 TCID50/ml G10, Changchun024, Changchun045, Changchun090 viruses in DMEM medium. The negative control mice were given medium instead of the virus suspension. The survival rates (A) and clinical scores (B) were monitored and recorded daily after infection for 21 days. The clinical score was graded as follows: 0: no abnormalities; 1: lethargy and inactivity; 2: wasting; 3: limb shake weakness; 4: hind-limb paralysis; 5: moribund or dead. Each group contained six to ten mice.