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:

Introduction There is an urgent need to check the efficacy of SARS-CoV-2 vaccination among hemodialyzed (HD) patients known to have extensive disturbances of acquired immunity and a catastrophic risk of death from COVID-19. Objectives In a cross-sectional study we aimed to assess the humoral response following vaccination with the BNT162b2 (BioNTech / Pfizer Comirnaty) vaccine. Patients and methods We analyzed the titer magnitude of the IgG antibodies directed against spike (S)- SARS-CoV-2 antigen 14-21 days after the second dose of the BNT162b2 vaccine in a group of HD patients who have not been confirmed with SARS-CoV-2 infection yet, compared to patients with a history of COVID-19. 126 HD patients were stratified based on evidence of a previous infection with SARS-COV-2 confirmed with viral RNA detection or nucleocapsid-specific IgG antibodies detection. Results s-antigen immune response with a median (IQR) antibody titer of 366 (193-691) UA/ml was seen in 87 of 91 infection naive (IN)-HD patients (95.6%). In 68 of 91 IN-HD patients (74.7%) a strong humoral response was observed with titer anti-S antibodies above 200 UA/ml. Older subjects were less likely to develop an S-antibodies response (P <0.001). The median S-antigen antibody titer in 35 previously infected (PI)-HD patients was over 12-fold higher than in IN-HD patients; 4620 (1240-7820) UA/ml (P <0.001). There were no significant differences in S-antibody titer between symptomatic and asymptomatic PI-HD patients. Conclusions Our study demonstrated that the majority of HD patients achieved a high immunization rate after vaccination with BNT162b2. Whether this translates into protecting this population from COVID-19 requires further research.
["Diagnosis", "Treatment"]