“They were still talking about polio, now by recalling its frightening precursors. His grandmother was remembering when whooping cough victims were required to wear armbands and how, before a vaccine was developed, the most dreaded disease in the city was diphtheria. She remembered getting one of the first smallpox vaccinations. The site of the injection had become seriously infected, and she had a large, uneven circle of scarred flesh on her upper right arm as a result.”