Listeria bacteria. Coloured transmission electron micrograph (TEM) of a Listeria monocytogenes bacterium (centre to bottom right). It is dividing by a process of unequal cell growth known as budding. Its progeny, or daughter cell, is seen at upper left. It causes listeriosis, a form of food poisoning that results in abdominal pains, fever and diarrhoea. Severe infections can be fatal. It is widespread in the environment, parti- cularly in soil, and is contracted from contaminated foodstuffs. Sources of human infection include milk, soft cheese and improperly cooked meat. Treatment is with antibiotic drugs. Magnification: x66,000 at 6x7cm size. x233,000 at 7x9.5"~LANDSCAPE"