Fig. 1From: A high throughput serum bactericidal assay for antibodies to Haemophilus influenzae type bMicro-colonies of Haemophilus influenzae type b on a BHI agar plate with an agar overlay containing TTC. The average diameter of the micro-colonies was about 0.3 mm and the red colonies were distinct and could be readily counted with NICEBack to article page