Assignment task #1
1. According to Centers for Disease Control and Prevention, 2012), no single isolated cause is the source of an event but rather the event develops from a chain of causation, preceding events link to one another. John Snow believed that most of the people that died drank water from the Broad street pump. The preceding events however were that the people dumped fecal matter into the well, bacteria (vibrio cholerae) began to multiply, people would ingest this contaminated water, bacteria multiples in the gut leading to death (Harvard Online, 2017). John Snow was successful in establishing a cause because after his theory was tested, the epidemic stopped.
2. The outbreak I chose to research was Salmonella caused by cucumbers grown by Bedner's Growers Inc., and distributed by Fresh Start Produce Sales Inc., affecting three Florida locations including Boynton Beach, Delray Beach, and West Palm Beach between April 29, 2025, and May 2025 (USFDA, 2025). This outbreak would be considered an epidemic because it was a sudden increase in the number of cases above what is normally expected in a given population (Florida) (Centers for Disease Control and Prevention, 2012). This mode of transmission is horizontal, indirect food borne mode of transmission. According to the U.S. Food & Drug Administration (2025), investigators collected an environmental sample from Bedner Growers, Inc. that was positive for Salmonella. This sample was analyzed by the Whole Genome Sequencing (WGS) and matched clinical samples from sick people infected with salmonella. This recent follow-up was in response to a 2024 Salmonella Africana and Salmonella Braenderup outbreaks linked to the same Bedner Growers (United States Food & Drug Administration, 2025). In comparison to the strategies used by John Snow, the strategies align that there was an outbreak of salmonella. 551 illnesses were recorded. Investigations showed that Salmonella Braenderup was detected in samples of canal water used at the farms that grew the cucumbers, people purchased these cucumbers and got sick. Need Assignment Help?
Assignment task #2
How did John Snow use the web of causation related to cholera? Why do you believe that Snow was successful or unsuccessful in establishing a cause? Remember to cite evidence to support your position. It can be from the resources within the course.
The web of causation is a model of understanding the causes of a medical condition or disease in a community. It addresses the specific relationships the individual with the condition has with the possible causes (Swift, 2022). Regarding John Snow, he used the web of causation for cholera and included causes from contaminated water, poor sanitation, and weather conditions. Snow found that the cause of the London cholera outbreak was from contaminated water. He realized that contaminated water from the Broad Street pump was the origin of the cholera. He persuaded the authorities to remove the handle from the Broad Street pump, and the epidemic disappeared within a few days. He also observed cholera in London homes that were receiving their water from two water systems. One water supply system was from the sewage-contaminated portion of the Thames River, and the other system drew its water upstream from part of the river that was uncontaminated (Tulchinsky, 2018).
Select a disease/outbreak to research. Discuss the level of the disease and type of transmission. As you review the selected disease/outbreak, describe the investigative strategies used, and explain how these aligned (or did not align) with strategies used by John Snow. Use one scholarly journal to support your research.
The disease/outbreak I decided to research is polio. Polio is an infectious disease that is caused by a virus that mainly affects nerves in the spinal cord or brain stem. It is transmitted by food, water, or the feces from a patient with the disease, or it can be transmitted through droplets. In 2022, the UKHSA (United Kingdom Health Security Agency), had found the polio virus in samples collected from the Beckton sewage works, which served a population of four million in north and east London. Like John Snow finding cholera, polio was also found in the water system. Polio mainly affects young children, leading to irreversible paralysis and, in some cases, death. I was interested in researching this disease because my grandma had polio. She was diagnosed when she was around 35 years old. She lived to be 93 years old. Luckily, she didn't have a severe case, but she had some paralysis in her neck and throat, which caused her to choke often. In 1908, Karl Landsteiner and Erwin Popper showed that polio was caused by a virus after taking the spinal fluid from a person who had died from polio and putting it through a filter that prevented bacteria from passing through. The fluid was then injected into monkeys, which developed polio. This provided proof that polio wasn't caused by bacteria but by the polio virus (Eggers, 1999).