By April 3, 1962 as many as 27,000 East Berliners were infected with a disease traditionally associated with poverty, destitution and/or war: dysentery.

This highly contagious and potentially deadly disease - whose symptoms include acute diarrhoea with blood in the stool, fever and general loss of liquids - leads to life-threatening dehydration. Known as Ruhr, in the twentieth century it came to be associated with army barracks, with war and with Nazi concentration camps.
And this was one of the reasons why - even though they had known about the outbreak for at approximately a week - East German authorities were desperate to keep a lid on the news about it.