Do you mean ter tell me," he growled at the Dursleys, "that this boyโthis boy!โknows nothin' abou'โabout ANYTHING?" Harry thought this was going a bit far. He had been to school, after all, and his marks weren't bad. I know some things," he said. "I can, you know, do math and stuff.
J. K. RowlingRemus Lupin was supposed to be on the H.I.V. metaphor. It was someone who had been infected young, who suffered stigma, who had a fear of infecting others, who was terrified he would pass on his condition to his son. And it was a way of examining prejudice, unwarranted prejudice towards a group of people. And also, examining why people might become embittered when they're treated that unfairly.
J. K. Rowling