After receiving M.Sc degree from University of Calcutta he joined as a junior research fellow at the National Institute of Cholera and Enteric Diseases. His research work on Vibrio cholerae O139 bacteriophages resulted in the development of a phage typing scheme for the identification and discrimination of highly virulent Vibrio cholerae O139 which is in routine use for nationwide screening of phage types ofVibriocholerae O139. After completion of his PhD work, he moved to USA as a post-doctoral researcher where he gained expertise on virology. He worked on generation of recombinant influenza viruses to use influenza virus as a vector for gene transfer at UCLA Los Angeles. At UTMB, Galveston he performed research on replication of HIV-1. Afterwards he joined National Institute of virology, Pune asa regular faculty and worked on influenza viruses. Consequently he became in charge of Microarray Division at the National Institute of Virology. His research at NIV, Pune on molecular diagnostics of influenza contributed largely in management of bird flu outbreak in India during 2007-2008. He developed reverse genetics modified vaccine strain for the highly pathogenic H5N1 influenza A viruses in collaboration with CDC, Atlanta, USA. His work on host influenza virus interactions revealed that delicate differences in the ability to induce specific host responses like apoptotic mechanism and immune responses make the highly pathogenic viruses (H5N1) more virulent.His work also attributed the high transmissibility of pH1N1 virus in the year 2009-2010 to its better subversion of host immune responses compared to the seasonal influenza viruses. Besides research and training Dr Chakrabarti also worked as a faculty for teaching MSc Virology at National Institute of Virology, Pune University for 10 years and also worked as invited faculty for the Department of Biotechnology at Pune University. Other than working for many institutional committees at NIV, he was also the in-charge of NIV library as an additional charge.
He joined NICED as Scientist in July, 2016 and working on respiratory viruses.
His field of research interest includes work on respiratory viruses, as well as host-pathogen interactions.A major focus of his research is on influenza viruseswhich are one of the globally important human pathogens and a leading public health risk problem. Emergence of highly pathogenic avian influenza (HPAI) strains and pandemic H1N1 indicated a persistent need to work on influenza viruses to understand the pathogenesis of influenza A and development of vaccines and therapies. He is working oninvestigating the molecular pathogenesis and biology of influenza viruses.