The beast in the mosquito: the correspondence of Ronald Ross and Patrick Manson

The correspondence between Ronald Ross and Patrick Manson documents one of the legendary collaborations in the history of medicine and science in the nineteenth century. Their four-year collaboration (1894-1898) led to the discovery of the transmission of the plasmodia protozoa in the bite of the mosquito. With the advantage of a century of research, it is easy to look back on their achievement as one in a long series of breakthroughs. This was hardly the case. Even Charles Alphonse Laveran, who in 1880 proposed a causal relationship between the presence of pigmented bodies in the blood and malaria disease, faced a chilly reception for five years. Thereafter, researchers in Italy elaborated the asexual stage of the plasmodia in the human body. There was still no consensus about the meaning of the crescent and flagella forms, that is the equivalent of the sexual stage of the protozoa outside the bloodstream. In December 1894 Manson inserted himself into a growing international competition. Observing the transformation of the protozoa from cjescent to flagella after extraction from the bloodstream, Manson theorized that a suctorial insect, possibly a mosquito, served as its intermediary host. Asserting this relationship was one thing, proving it was another. The task required illuminating the hitherto unknown biology of a complex protozoa in the mosquito while identifying the proper species of vector. In other words, the theory involved the creation of fundamental knowledge before its demonstration was practically possible. Few individuals in Britain possessed the needed combination of skills or were interested in the malaria problem itself. For his part, Manson's declining health ruled out an open-ended research expedition. Nor did cultivating his practice allow for the concentration needed for basic research. What Manson needed above all was a collaborator. Surgeon-Major Ronald Ross proved to be ideally suited for this role. Sigmund Freud would have had a field day with Ross. Like other Anglo-Indian parents, Campbell and Matilda sent Ronald at the age of eight to England. A latent sense of parental abandonment turned to betrayal when Ross reached his seventeenth birthday. Instead of allowing him to attend the university which he preferred, his parents decided on a career in the Indian Medical Service. The signs of rebellion subsequently littered his early career in medicine. He neglected his studies at St Bartholomew's Hospital; initially failed the Apothecaries' licentiate examination and secured a low pass score on the Indian Service examination. Rebellion, ironically, condemned Ross to the purgatory of the military branch of the Indian Service where for fifteen years he held only one permanent posting. As a borderline paranoid, Ross rationalized his stalled career. Convinced that his intellect was unappreciated, he sought the learning denied him. No matter how much he poured himself into mathematics and literature, they failed to satisfy his longing for external validation. In a pattern that would define his research style, Ross oscillated between the promise of confirming his genius and the reality of