Ronald Ross

British physician and scientist

• Born: May 13, 1857
• Birthplace: Almora, India
• Died: September 16, 1932
• Place of death: Putney Heath, London, England

Ross demonstrated the role of the mosquito in the transmission of malaria, proved the insect to be essential to the life cycle of the malarial parasite, and introduced the first effective preventive measures against malaria.

Early Life

Ronald Ross was the oldest of ten children born to General Sir Campbell Claye Grant Ross, a Scotsman and British army officer in India, and Matilda Charlotte Elderton, the daughter of a London lawyer. While three Ross generations had served as fighting officers of the British Empire, a gentler stream also flowed into young Ross. His father was a skillful watercolorist of Indian scenery, and both parents loved music and poetry.

In 1865, Ross went to England for his education, living first on the Isle of Wight with an aunt and uncle and then at a school near Southampton until he was sixteen. When he left school, he showed no special promise, but he had developed a passionate interest in the arts and thought that he would be an artist. His father insisted that art was suitable only as a hobby and urged his son to enter the Indian Medical Service (IMS). Ross, with no inclination toward medicine, deferred to his father out of a sense of duty. In 1874, he began his training at London’s St. Bartholomew’s Medical School. He found medical studies difficult and never became a good student.

Ross needed to fulfill both surgery and medicine requirements to qualify for the IMS. He put off study until the last moment but passed the examination in surgery. This success gave him the notion that he could get away with studying even less for the medical requirement. He failed badly. After serving as ship’s surgeon on a transatlantic liner, he qualified for the IMS and returned to India in 1881.

In India, Ross saw his future in terms of writing, and throughout his life, he wrote plays, romances, novels, fables, and poetry. He also threw himself into mathematics, developing a new theory of algebra. By 1885, Ross had served in Madras, Bangalore, Burma, and the Andaman Islands, enjoying the perquisites of a British officer. His novel The Child of Ocean (1889), set in the Andaman Islands, was highly praised by some critics, by others less so, although most thought Ross might become an important writer.

While Ross felt strongly about his writing, he was also aware of a lack of direction in his life. By 1888, he had received no promotion and no permanent position. He became despairing and neglected his medical duties. He threatened to resign unless granted a leave. His demand met, he returned to England for a year. He pursued his literary interests and took a diploma in public health. While on leave, he met and married Rosa Bloxam in 1889. They had two sons and two daughters.

Ross was powerfully built, and his wax-tipped, upturned military mustache and close-cropped hair gave him a bold appearance. He could not tolerate what he took to be stupidity or incompetence, and he lashed out at officials and fellow officers. His pugnacious and egotistical personality aroused hostility and created difficulties. Ross was also a melancholic dreamer and poet with a passionate curiosity and could be kindly and genial. He reflected the British upper-class attitude of superiority in India. To Ross, the British were a true aristocracy ruling an inferior people.

Life’s Work

By 1890, Ross had published two volumes of poetry and two novels and had attempted to create an algebra of space and time. Medicine was secondary to him. While serving in Secunderabad, however, a large military post on a vast plain with lakes, his medical conscience awakened in the face of awesome medical problems, most especially the prevalence of malaria . He read all that he could about the disease, its symptoms, and the miasmatic theories of emanations from marshes. He read also of the 1880 discovery by Alphonse Laveran, a French army surgeon in Algeria, of a parasite in the blood cells of malarial patients. These crescent-shaped bodies on examination outside the body threw off flagella, little moving filaments. The parasites were protozoa of the Plasmodium genus. Ross wanted to understand malaria, and with a crude microscope, he tried to find the parasite in the blood of malaria patients, with no success. He became skeptical of its existence. He was floundering, and because the IMS did not encourage research, there was no one to advise him.

In 1894, Ross returned to England for his second leave. In London, the key figure in his career suddenly entered his life in the person of Sir Patrick Manson, an expert on tropical diseases. Manson took him to Charing Cross Hospital to show the skeptical Ross the parasite in the blood of patients. He directed Ross to publications and told him of a theory he had on how malaria was transmitted. In 1877, Manson had discovered the small parasitic worm in human blood that caused elephantiasis. Mosquitoes sucked the blood, and the worm developed in the mosquito. Manson suggested that the same might be true with malaria. Laveran’s parasite might be transferred to a mosquito. Perhaps when mosquitoes laid their eggs in pools of water, the parasite escaped, and when people drank the water the parasite entered the human system to cause new cases of malaria. Ross now had an intense desire to return to India and test this mosquito theory. To replace his inadequate microscope, he invented a small portable one and had it made in London to take back with him to India. At the same time, he managed to finish two novels.

Back in India, with a promotion to major, Ross worked furiously for the next four years in his spare time from medical duties. He wrote 110 letters to Manson, pouring out his questions and difficulties; Manson replied regularly with answers, suggestions, and encouragement. At Secunderabad in 1895, Ross elaborated techniques for dissecting the internal organs of mosquitoes. Malarial patients volunteered to submit to the bites of mosquitoes captured by assistants. Ross then dissected the mosquitoes. His mosquitoes were the Culex and Aëdes types of the region. He proved that the parasite formed spheres in the stomachs of mosquitoes and that some gave off flagella, but this process took place in the blood itself when drawn from a patient. Something further must happen to the flagella, but he could find nothing. He did disprove Manson’s drinking water theory; volunteers who drank water contaminated by malarious mosquitoes did not get the disease. The IMS saw no value in Ross’s research and placed a series of obstacles in his way. For eighteen months, following a transfer to Bangalore to direct sanitary measures, he could do no research. During that time, however, the idea came to him that the parasite got into the healthy person the same way it got out of a sick one, by the bite of a mosquito.

In 1897, Ross returned to Secunderabad. His assistants caught some mosquitoes of a different type, not gray or brindled like the Culex or Aëdes ones but brown with dappled wings. He tested these on volunteers. With but two mosquitoes left, he dissected one on August 20, 1897 (Mosquito Day), and saw a cyst on the stomach wall, a new stage in the parasite’s life. He examined his last mosquito the next day. The cells were larger; the parasite had grown. Fortunately, Manson had informed him of a recent discovery that enabled Ross to realize what he had observed. William MacCallum at Johns Hopkins that same summer saw the flagellation process and proved that the only cells that threw off flagella were male gametes, one of which penetrated a female cell and fertilized it. In addition to its asexual phase in human blood, the parasite had a sexual phase in its life history. Ross’s cyst was part of that phase, and he immediately incorporated MacCallum’s discovery into his research.

Ross thought that it would be a matter of a few weeks to unravel the whole life cycle of the parasite. Then came his biggest disappointment an order to go to Bombay immediately. His research was at the breakthrough stage, but he was not to see the Plasmodium parasite for two years. Ross was bitter, especially since he was assigned to a small post near Bombay, simply as a replacement for an officer on leave.

In 1898, through Manson’s urging, Ross was granted six months for research in Calcutta. There, however, he had no malaria cases. At Manson’s suggestion, he studied avian malaria, since birds got malaria, had parasites in their blood, and were bitten by mosquitoes. He found that the gray Culex mosquito bit birds and carried the parasite in its stomach. He traced the full life cycle of the parasite from the fertilization of a female cell through the formation of spores that burst, releasing threads into the mosquito’s body cavity and thence into the salivary gland. These germinal threads were the agents that invaded the healthy bird when the mosquito bit it. He confirmed the process by producing the disease in healthy birds by the bite of mosquitoes fed on infected birds. Ross’s was the basic work in the field. Surely, the same process must take place in human blood and the dappled-wing mosquito.

When Ross requested more time for research, his superiors instead ordered him to Assam, denying him once again a chance to work on human malaria. When later in 1898 Italian scientists made the breakthrough he had hoped for by demonstrating the life cycle of the Plasmodium in human blood and in the Anopheles mosquito, Ross angrily claimed that they had stolen everything from him and refused to acknowledge the independence of their work. His bitterness was lasting. His Memoirs with a Full Account of the Great Malaria Problem and Its Solution (1923) is full of attacks on the Italians as thieves and pirates.

Ross decided to resign from the IMS and return to England in 1899. Publication of his avian malaria report made him famous. He planned to devote his life to the prevention of malaria; the way was clear, since the Anopheles mosquito was the sole mode of infection and it bred chiefly in stagnant water. He believed that it would take only a few years to rid the world of malaria by drainage and larvicide programs. He accepted an appointment as lecturer at the new Liverpool School of Tropical Medicine, the first of its kind. He used his position to undertake sanitary expeditions between 1899 and 1914. His optimism proved unwarranted; the world would not be rid of malaria in a few years. His initiatives did not proceed as quickly as he thought they should, in part as a result of the lack of cooperation by political authorities, in part because of the complexity of the problem. Nevertheless, his efforts significantly reduced the incidence of the disease, and his expeditions to malarial regions gave the Liverpool school its fame and prosperity.

In 1902, Ross received the Nobel Prize. His main contribution to the literature of malaria control was the classic, The Prevention of Malaria (1910), which gave a full account of antimalaria work in many countries. Ross was especially pleased when American officials cleared Panama of the mosquitoes responsible for malaria and yellow fever (1904); he believed they had set an example for the rest of the world.

In 1911, Ross received knighthood. During World War I, his first son, Ronald Campbell, an officer in the Royal Scots Regiment, was killed in action. Ross served during the war as consulting physician on tropical diseases and went overseas to deal with outbreaks of disease among British troops. His memoirs graphically depicted the torpedoing of his ship on a 1917 expedition to Greece.

In 1922, a letter signed by prominent persons on the twenty-fifth anniversary of Mosquito Day declared the importance of Ross’s discoveries. The letter led to the founding in 1926 of the Ross Institute and Hospital for Tropical Diseases in Putney, near London, with Ross as director. It became an important center for malaria research, continuing its existence after 1933 as part of the London School of Hygiene and Tropical Medicine.

Although when Ross’s memoirs appeared in 1923 he was full of resentment over his experiences in India and the slow progress in malaria control, his attitude changed when his pupil, Malcom Watson, went to Malaya and won an impressive victory over malaria by 1926. Ross went there to see for himself, the first example of all-out war against malaria in the British Empire.

Several of his literary endeavors were published during the 1920’s, including a collected edition of his poetry, Poems, in 1928. The deaths of both his younger daughter and his wife preceded his death, which came after a long illness, at the Ross Institute on September 16, 1932.

Significance

Ross’s work was part of a series of investigations on malaria involving many scientists in different parts of the world and whose work linked together to unravel the nature of malarial fevers, the mode of transmission, the life cycle of the pathogen, and the measures to control the disease. His discoveries illuminated malariology profoundly, revealing the unsuspected mechanism of transmission by the mosquito and the sporogonic cycle of the parasite in it. Furthermore, Ross’s work provided key insights for other investigations of tropical disease, especially yellow fever.

Bibliography

Bynum, W. F. “Mosquitoes Bite More than Once.” Science 295 (January 4, 2002): 47. This article about malaria includes information about Ross’s role in discovering the biological cause of the disease.

De Kruif, Paul. “Ross versus Grassi: Malaria.” In Microbe Hunters. New York: Harcourt, Brace and World, 1926. De Kruif presents the dramatic story of both Ross and the Italians, trying to sort out who did what and what the controversy was about.

Gorgas, William C., and Fielding H. Garrison. “Ronald Ross and the Prevention of Malarial Fever.” Scientific Monthly 3 (August, 1916): 132-150. A perceptive article by Gorgas, the leader of the mosquito campaign in Panama, and Garrison, the historian of medicine, on Ross’s pioneering control efforts.

Kamm, Jacqueline. Malaria Ross. London: Methuen, 1963. A clear, straightforward, popular biography based on Ross’s memoirs but supplemented with a valuable account of his last ten years.

Mégroz, Rodolphe L. Ronald Ross: Discoverer and Creator. London: Allen and Unwin, 1931. In addition to Ross’s life and malaria work, this is a study of Ross as a writer, claiming he has been unduly neglected and praising him as a fine novelist and poet.

Nuttall, G. H. F. “Sir Ronald Ross.” Obituary Notices of Fellows of the Royal Society 1 (1933): 108-115. The best account of Ross’s career in the context of his time.

Ross, Ronald. Memoirs with a Full Account of the Great Malaria Problem and Its Solution. London: John Murray, 1923. Indispensable reading for anyone wishing to understand the man and his lasting anger and bitterness and for the presentation of the minutest details of his research.

Russell, Paul F. Man’s Mastery of Malaria. Oxford, England: Oxford University Press, 1955. A good, clear retrospective picture of malaria through history with chapters on the parasite, the mosquito, control methods, and much more. All the major figures are lucidly discussed.

Spielman, Andrew, and Michael D’Antonio. Mosquito: A Natural History of Our Most Persistent and Deadly Foe. New York: Hyperion, 2001. Includes information about Ross’s discoveries about malaria.

Yoelli, Meir. “Sir Ronald Ross and the Evolution of Malaria Research.” Bulletin of the New York Academy of Medicine 49 (August, 1973): 722-735. The most perceptive study on Ross and the major investigators from the point of view of medical science.