During the patrol's absence the weather had taken a turn for the worse. Not only was it now unbearably hot, but a violent six hour dust storm on the 2nd was repeated daily for a fortnight. Then, the worst news of all. On Tuesday 11th, cholera was reported to have broken out in the French lines. By the 19th it had spread widely through the French Camps and on the 23rd hit the British Light Division.
Cholera is caught by drinking water or eating food contaminated with vibrio cholorae bacteria.
The toxin causes massive excretion of body fluids. After an incubation period of up to 28 hours, the onset of abrupt and massive attacks of diarrhoea is quickly followed by vomiting. In the resultant dehydration, the skin grows cold and the eyes sunken. Blood pressure drops and excrutiatingly painful body cramps and raging thirst are common. With increasing dehydration, the patient can drift into a coma and death through shock occurs.