Nath received her MBBS from
All India Institute of Medical Sciences (
AIIMS), New Delhi. She joined
AIIMS as MD (pathology) after mandatory hospital training in the UK. During the 1970s, India has the world's largest number of
leprosy patients of 4.5 million. In 1970, Nath was in the UK with a Nuffield Fellowship. During this period, she came to specialise in immunology. She worked in the area of infectious diseases, particularly leprosy, with Professor John Turk at the
Royal College of Surgeons and Dr. RJW Rees at the
National Institute for Medical Research, London. She saw the importance of getting experience abroad but did not want to add to the brain drain out of India. She and her husband made a pact to return to India after 3 years abroad. She returned to India in the early 1970s. “Still, it was quite an exciting time to come back because you felt you could really play a role in building up research,” she said in an interview published on Nature Medicine in 2002. After coming back to India, she joined Professor
Gursaran Talwar's Department of Biochemistry at AIIMS, which had just initiated immunology research in India. Later in 1980 she moved to the Department of Pathology and she founded and established Department Biotechnology (1986) at
AIIMS. She retired in 1998 but continued to work at AIIMS as INSA-SN Bose Research Professor. She was one of 100 scientists gathered by Rajiv Gandhi when he became Prime Minister to make suggestions to improve Indian science. She received DSc from
Pierre and Marie Curie University, Paris in the 2002. She was invited for the post of Dean of
AIMST University in Malaysia and also as Director of Blue Peter Research Centre (Lepra Research Centre), Hyderabad. ==Research==