Case of Filaria loa is a fascinating medical narrative authored by Thomas R. Fraser, originally published in the late 19th century. The book meticulously documents a rare and intriguing case of infection by the parasitic worm Filaria loa, also known as the African eye worm, which is endemic to certain regions of West and Central Africa. Through detailed clinical observations, Fraser recounts the symptoms, diagnosis, and progression of the disease in a patient, providing valuable insights into the medical understanding of filarial infections during that era. The narrative delves into the patient's history, the onset of peculiar symptoms such as localized swelling, itching, and the dramatic migration of the worm across the conjunctiva of the eye-a hallmark of Loa loa infection. Fraser's account is enriched by his careful examination of the patient, the methods employed to extract the worm, and the subsequent analysis of the parasite's morphology. The book also discusses the broader implications of such infections, including their epidemiology, transmission by Chrysops flies, and the challenges faced by physicians in diagnosing and treating tropical diseases unfamiliar to European medicine at the time. Case of Filaria loa stands as both a medical case study and a historical document, reflecting the scientific curiosity and clinical rigor of its author. It offers readers a window into the complexities of tropical medicine, the evolution of parasitology, and the human stories behind medical discoveries. This work is an essential read for those interested in the history of medicine, parasitology, and the global challenges posed by infectious diseases.