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:

Objectives: To report the person-to-staff transmission of COVID-19 with the implementation of a bubble concept that included testing, hygiene, distancing and monitoring strategies to mitigate risks. Methods: A prospective case series included all staff on-site involved in the Football Club World Cup. The tournament was conducted within 'bubbles'. All personnel travelling to the tournament were required to be in possession of a negative RT-PCR test within 72 hours of arrival and subjected to a testing schedule during the tournament. Each location was assigned a COVID-19 protocol enforcement officer to ensure adherence to regular testing, hygiene measures, physical distancing and daily symptom reporting (via ScribePro app). Results: The study involved 70 recruited staff with a combined 1321 test days on the symptom checker app. The mean number of days completed on the symptom checker app was 18.87 days (range: 7-28). Of the five questions asked as part of the daily symptom checker, only one was answered positively (0.015%). This individual was isolated, assessed within 20 min and tested. The initial diagnosis was likely a non-COVID-19-related viral illness. Further testing returned three negative tests during the remainder of the tournament. Conclusions: There was no person-to-staff transmission of COVID-19 during the tournament within our sample. The organisation of a sporting tournament during the COVID-19 pandemic is possible with risk mitigation strategies. These strategies include setting up a bubble with regular testing, hygiene measures, physical distancing and daily symptom reporting.
["Prevention"]