Vas retired as senior scientist from the National Institute of Malaria Research, New Delhi – an apex organization of the Indian Council of Medical Research. He was the officer-in-charge of the Field Station based in Assam, northeast India beginning 1988 till his superannuation in 2016. His primary research interests included ‘Epidemiology and Control of Malaria’ testing newer interventions that culminated in number of technologies and implementation in the control programme resulting in substantial transmission reduction.