instruction: provide me the number of patients who have abnormal lab test status and diagnosed for the need for prophylactic vaccination and inoculation against viral hepatitis.
response: SELECT COUNT(DISTINCT demographic.subject_id) FROM demographic INNER JOIN diagnoses ON demographic.hadm_id = diagnoses.hadm_id INNER JOIN lab ON demographic.hadm_id = lab.hadm_id WHERE diagnoses.short_title = "Need prphyl vc vrl hepat" AND lab.flag = "abnormal"