[4] In 1952 he joined the fledgling Virus Research Centre in Pune, and worked under the supervision of some of the finest vector control specialists such as Dr T Ramachandra Rao.
[5] In recognition of his outstanding work as a young research scientist, in 1957 he was awarded a Fellowship by the Rockefeller Foundation to pursue a Master's program in Public Health from the University of California.
[8] His pioneering work on the role of migratory birds in spreading disease vectors as part of the investigation into KFD, conducted under the supervision of the ornithologist the late Dr Salim Ali, led to his doctoral degree from Pune University.
[12] However its flagship achievement under the leadership of Dr Rajagopalan was to pioneer the technique of Biological Control, which combined minimal chemical intervention with environmental measures and the use of natural mosquito larval predators to bring down the incidence of diseases like filariasis.
[25] He had the privilege of learning Ecology under Charles Elton at Bureau of Animal Populations, Oxford, and Acarology under Dr Hoogstraal, US Naval Medical Research Unit in Cairo during his career.