Cholera outbreaks and pandemics
That year, cholera was transmitted along the California, Mormon and Oregon Trails as 6,000 to 12,000 are believed to have died on their way to the California Gold Rush, Utah and Oregon in the cholera years of 1849–1855. It is believed more than 150,000 Americans died during the two pandemics between 1832 and 1849.
Oregon Trail
At dangerous or difficult river crossings, ferries or toll bridges were set up and bad places on the trail were either repaired or bypassed. Several toll roads were constructed. Gradually the trail became easier with the average trip (as recorded in numerous diaries) dropping from about 160 days in 1849 to 140 days 10 years later.