In the 19th century, diseases like smallpox, cholera and TB were insatiable and continued to relapse in epidemical waves in Britain. The situation was so severe that middle class men lived up to an average of 45 years, while the average workmen and labourers lived just half that duration. Children were lucky to survive their fifth birthdays.
1831 saw the first cholera epidemic in which 13,000 died, followed by recurrent waves up to 1853. Its onset was rapid with death occurring often within 24 hours. But how did it become so bad?
After the war with France, Britain was economically strained. They also experienced a population boom of 2.5 million and growing. This put a lot of pressure on London as more people moved in from rural communities in search of job opportunities.
Real estate were in a very poor condition - damp and rotten.
Families were crowded in small spaces with no sanitation - no drains or sewers, and over 200,000 cesspools.
No formal rubbish collection.
Animal markets and slaughter houses with animal waste left to rot in the streets.
Most of this filth was discharged or washed down into the River Thames, deteriorating its water quality and resulting in The Great Stink - locals believed that bad smells caused the diseases. This was because of an observation that in poor districts the air was foul and the death rate was high, whereas in the prosperous suburbs, there were no smells and low death rates.
This wrong belief was accompanied by the closure of some cesspools, leaving the remaining sewers overwhelmed, and more human waste was disposed into River Thames.
London's water supply was also contaminated during the process as some companies provided unfiltered water to their customers that was taken from the River Thames. In a study conducted, it was found that companies distributing filtered water did not result in their customers falling ill.
It took Dr John Snow years to persuade the establishment that cholera is a water-borne disease. Following this revelation, the epidemic was eventually eliminated in industrialized countries by the introduction of municipal water supply that needs to be filtered before being piped to city residents.
Water filtration has since evolved, from playing a key role in keeping diseases at bay to ensuring the purity of semi conductors in manufacturing hard disks.