According to the World Health Organization, nearly half of the world’s population was at risk of malaria in 2021. A life-threatening disease that is mostly found in tropical countries, the African region carries the bulk of the global malaria burden. The fact that it is now preventable and curable is thanks to Ronald Ross, whose discovery led to the realisation that the spread of the disease in humans was by some types of mosquitoes.
Ronald Ross was the son of Campbell Claye Grant Ross, a General in the Indian Army, and his wife Matilda. Born in 1857 in Almora, India, Ross was sent to England for his education at the age of eight. He spent most of his childhood with an aunt and uncle at the Isle of Wight, developing his interests in poetry, music, literature, and mathematics – interests that remained close to his heart for the rest of his life.
To fulfil father’s wish
Even though he had no inkling to take to medicine, he began his medical studies at the age of 17 in order to fulfil his father’s wish of seeing him enter the Indian Medical Service. He entered the Indian Medical Service in 1881 and had brief stints in Madras, Burma, and the Andaman Islands.
Between 1888-89, when he took a year’s leave, he got married, saw his scientific interest develop, and even took a course in bacteriology under renowned bacteriologist Emanuel Edward Klein. In 1894, Ross met Patrick Manson, considered by many as the father of tropical medicine, for the first time. Manson spoke about the problems surrounding malaria research and his influence completely changed Ross’ perspective.
From doubter to believer
From originally doubting the parasites’ existence, he was totally convinced by Manson that the malaria parasites were in the bloodstream. His interest and excitement in the subject was so piqued, that he set out to prove what was then a hypothesis that mosquitoes were connected with the propagation of malaria. Upon his return to India, considered a place well-suited for this study, he set out on this task immediately in 1895.
Ronald Ross.
It was on August 20, 1897 that Ross made his now landmark discovery in Secunderabad. On that day, Ross found the malaria parasite while dissecting the stomach tissue of an Anopheles mosquito. He was able to confirm the growth of the parasite in the mosquito the following day and take his discovery to the world quickly.
Ross’ contribution didn’t end with this discovery as he continued his research into malaria in India. He picked a more convenient experimental model to further his studies by using birds that were sick with malaria.
Mosquitoes’ salivary glands
By studying these birds, Ross was able to establish the entire life cycle of the malarial parasite, which included the fact that the malarial parasites developed in the mosquitoes could migrate to the insects’ salivary glands. This was an important finding as it helped Ross demonstrate that malaria could be transmitted from an infected bird to a healthy one by the bite of a mosquito. The disease’s mode of transmission to humans soon became obvious.
On his return to England in 1899, Ross joined the newly established Liverpool School of Tropical Medicine. He won the Nobel Prize in Physiology or Medicine 1902 for his work on malaria and he was knighted in 1911.
In 1926, the Ross Institute and Hospital of Tropical Diseases and Hygiene was established in London by admirers of his work. Ross assumed the post of Director in Chief at the institute, a position he held until his death in 1932.
