How does Harry die?

Harry and his wife, Helen, have decamped to Africa for a more authentic existence, an existence far away from the shallow, pretentious lifestyle of their friends in Paris. However, a more authentic life carries its own risks—as Harry soon discovers. While out on safari with his wife, Harry pricks his knee on a thorn while trying to take a picture of some water-buck. Instead of treating the wound, he lets it fester, and it soon becomes gangrenous.
This sorry episode illustrates Harry's growing lack of self-worth as a husband, a writer, and a man. The wound was entirely preventable and could so easily have been treated. But Harry chose not to, and so now he lies on a cot—his deathbed—reflecting on various episodes of his life while his fatal gangrenous infection continues to spread unchecked.