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:

Coronavirus 2019 (COVID-19) disease has been a public health emergency of international concern with millions of confirmed cases globally. Closed environments with reduced ventilation contribute to the spread of COVID-19, including superspreading events. Exercising in closed places further increases the risk for transmission. Therefore, many fitness facilities were closed as part of mandated shutdowns early in the pandemic. Evidence-based safety protocols have now emerged and substantially reduce the risk of transmission. We report three positive cases of SARS-CoV-2 identified at a Dojo exercise facility in Manlius, NY, at three distinct time points. All cases were present in the Dojo 2 days prior to symptoms, a time period considered to be highly infectious. The safety protocols included universal mask wearing (no valves), multiple high-efficiency particulate air (HEPA) filters, and reduced capacity which resulted in no known spread of COVID-19.
["Prevention"]