Acinetobacter baumanii bacteria, coloured scanning electron micrograph (SEM). This bacterium has developed resistance to a number of antibiotics and is increasingly seen in opportunistic infections in hospitals. It typically infects the lungs, leading to a form of pneumonia. It can develop resistance to antibiotics even as they are being used to treat an infection. Because of this, and because it is generally found in weakened patients, the mortality rate for infections with A. baumanii is high. In healthy individuals, however, it is a normal part of the skin flora. Magnification: x11,000 when printed 10 centimetres wide.