While malaria is an illness that can recur throughout a person’s lifetime, Julian’s health was especially poor in India because he was repeatedly re-infected. In London, free from the mosquitoes who transmit malaria, he only had to suffer through the recurrences of the original infection. The tincture Eleanor gives him is made from the bark of the South American cinchona tree, which was used to treat malaria beginning in the seventeenth century. Quinine, which was isolated from this bark a few years after this story takes place, is still used as a treatment for malaria.