In 1832 a cholera epidemic broke out in East London, killing 800 people. A recurring disease, it claimed more than 6,000 lives between 1832 and 1851 in London alone: the rest of England, as well as Paris, Russia, Hungary, Germany, New York, Quebec and Egypt were also affected in this period. Cholera is a usually fatal sickness caused by drinking contaminated drinking water and was a widespread problem in the nineteenth century. This was responded to by huge social pressure and resulted in the building of the London sewer system, which stopped sewage being dumped directly in the River Thames, the source of the city’s drinking water. Cholera is still prevalent in the developing world, where it is thought to cause more than 100,000 deaths a year.