John, a 58-year-old retired teacher, went to see Dr. Rubin for his annual checkup. John has rheumatoid arthritis and is being treated with a drug that’s known to weaken the immune system. Moreover, John used to be a heavy smoker and has a history of heart disease. After asking him about his vaccination status, Dr. Rubin realized that John had never been vaccinated against pneumococcal disease. Indeed, John had no idea that adults even needed vaccinations other than the flu shot. He also didn’t think that pneumonia was that big a deal—couldn’t he just take antibiotics if he got it? Dr. Rubin explained that some types of pneumococcal bacterial could be resistant to antibiotics, meaning that if he developed pneumonia, it could be difficult to treat. Furthermore, John could be at risk of complications if he developed severe pneumonia. For these reasons, Dr. Rubin recommended that John get immunized against pneumococcal disease.