Resistant Streptococcus strain. Coloured Scanning Electron Micrograph of dividing Streptococcus pyogenes group A bacteria. This is the resistant strain implicated in the outbreak of necrotic fasciitis causing fatalities. The surface of this killer" strain is covered by ball-like structures, possibly protein. Necrotic fasciitis has rapid onset, leading to necrosis of large areas of connective tissue within hours. The infection is resistant to common antibacterial drugs. S. pyogenes is usually found in the nose and throat of healthy adults and is the most frequent cause of throat infections. Magnification: x20,000 at 5x7cm size. x64,000 at 10x8 inch size."