ABSTRACT

In the group of diseases, such as filariasis, texas fever, malaria and yellow fever, a cycle of the life history of the vector of infection takes place in a mosquito or tick, which also acts as an inoculator of the infective material. In 1876-1877 Bancroft discovered adult female worms of the micro-filaria in a lymphatic abscess, and Cobbold gave it the name of Filaria Bancrofti. He concluded that as the filaria did not grow in the blood it must be an immature form. The story of Theobald Smith's investigation of the source of Texas Fever is as fascinating as that of Patrick Manson on filariasis, of Ronald Ross on malaria, or of Walter Reed and his colleagues on yellow fever. On examination of the blood from the cattle which had died from Texas Fever, pear-shaped bodies were found in the blood and it was clear that these had devitalised the blood cells, and produced the characteristic symptoms of the disease.