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:

Great expectations are placed in vaccines against COVID-19 to control the pandemic. We reviewed the antibody titres in a cohort of healthcare workers (HCWs) vaccinated with BNT162b2 to assess the influence of a previous infection on them. We stratified the results according to the individual history of nasopharyngeal swab (NPS) and symptoms. Among 3475 HCWs the highest titres were recorded among those infected more than 6 months before vaccination, independently of symptoms, followed by those infected less than 6 months before vaccination, especially in those with symptoms, and by uninfected HCWs. Vaccination with BNT162b2 can boost immunity acquired through infection, particularly in those infected more than 6 months before vaccination.
["Treatment"]