Only 17 years after the first cholera epidemic (in 1832), New York City (NYC) was already heading towards another outbreak of the contagion. With its population doubled since the previous outbreak to approximately 500,000 residents, tightly packed tenement buildings and gloomy boarding houses sheltered most of Manhattan's poor. The streets, if they were messy before, had doubled the amount of accumulated waste; but no change in the sanitation system was made to accommodate this growth in population. Immigrants, particularly the Irish who were fleeing famine back home, made up the majority of the new influx of people. The cholera outbreak in 1849, originating somewhere in Europe, traveled all the way across the Atlantic Ocean though infected sailors. One of these trading ships was actually quarantined soon after its arrival on Staten Island; however, a few of the passengers escaped. Following the incident, cases of cholera began to emerge in the slums of the Five Points section of NYC. It was the beginning of spring when the spread of cholera began to pick up speed; by the end of that year approximately 5000 lives were lost.
During this period, doctors were even more ill prepared to deal with cholera than before. By 1849, laws requiring the licensing of doctors were abandoned in several states, resulting in inappropriate registering. Some doctors licensed themselves to gain an advantage in the market. However, many of these degrees required a mere six months of study to gain certification. The Board of Health was largely absent in fighting the cholera epidemic, although they set up a few cholera hospitals in various public schools throughout the city. Their inability to enforce basic clean-up operations and outright negligence of their responsibilities to NYC's sanitation, reflected poorly on their attitudes towards the epidemic.