You are presented with a paragraph from a COVID-19 literature. Classify the topics of this piece of text by choosing from the following categories:

- Epidemic Forecasting: The content relates to predictions about the spread of COVID-19.
- Treatment: The paragraph discusses therapeutic methods or medication for COVID-19.
- Prevention: The content covers measures to prevent the spread of COVID-19.
- Mechanism: The paragraph explains the biological mechanisms of the virus.
- Case Report: The content is a report of a COVID-19 case.
- Transmission: The paragraph discusses how COVID-19 is transmitted.
- Diagnosis: The content is about diagnosing COVID-19 in individuals.

Your classification should be provided as an element within a JSON array. The array should be formatted with topics enclosed in double quotes and separated by commas, following the JSON format, for example: ["Topic1", "Topic2", ...]. Include all applicable topics within the array. Your output should be a valid JSON array, and no additional text should be included in your response.

Article:

OBJECTIVE: Facilities that process and package meat for consumer sale and consumption (meatpacking plants) were early sites of coronavirus disease 2019 (COVID-19) outbreaks. The aim of this study was to characterize the association between meatpacking plant exposure and clinical outcomes among emergency department (ED) patients with COVID-19 symptoms. METHODS: This was a retrospective cohort study of patients presenting to a single ED, from March 1 to May 31, 2020, who had: 1) symptoms consistent with COVID-19 and 2) a COVID-19 test performed. The primary outcome was COVID-19 positivity, and secondary outcomes included hospital admission from the ED, ventilator use, intensive care unit (ICU) admission, hospital length of stay (LOS; <48 or >/=48 h), and mortality. RESULTS: Patients from meatpacking plants were more likely to be Black or Hispanic than the ED patients without this occupational exposure. Patients with a meatpacking plant exposure were more likely to test positive for COVID-19 (adjusted relative risk [aRR] = 2.37, 95% confidence interval [CI] = 1.59 to 3.53) but had similar rates of hospital admission (aRR = 0.94, 95% CI = 0.82 to 1.07) and hospital LOS (aRR = 0.76, 95% CI = 0.45 to 1.23). There was no significant difference in ventilator use among patients with meatpacking and nonmeatpacking plant exposure (8.2% vs. 11.1%, p = 0.531), ICU admissions (4.1% vs. 12.0%, p = 0.094), and mortality (2.0% vs. 4.1%, p = 0.473). CONCLUSIONS: Workers in meatpacking plants in Iowa had a higher rate of testing positive for COVID-19 but were not more likely to be hospitalized for their illness. These patients were disproportionately Black and Hispanic.
["Prevention"]