Figure 4. The K1 strains SGH04 and NUH27 were more virulent than the non-K1 strain NUH29.

Bacterial burden in the organs of mice upon intraperitoneal injection with 10⁴ or 10⁵ CFUs of SGH04, NUH27 and NUH29. Each dot represents one infected mouse, whose liver, spleen and lungs were harvested 24 hours post-infection. Tissue homogenates that yielded no colonies were plotted with the value 10 CFU/g, which is the approximate limit of detection. The upper limit of quantification is 10⁸ CFU/g.