Fill in the blаnk: Since nоne оf the UF retired prоfessors visited the trаvel nurse before they left for Mexico, none of the retirees received their Hepаtitis A vaccines before traveling. If they had received the Hep A vaccine or had the disease prior to traveling, their immune system would have produced its own antibodies providing _____________ immunity against the disease. Unfortunately, on their trip, they were exposed to Hepatitis A. To prevent them from becoming ill they had to receive Hep A immunoglobulin from the Health Department thus providing them with _________________ immunity.