Oommen has an MBBS and MD in Internal Medicine from Christian Medical College, Ludhiana and an Executive MBA from the Indian Institute of Management, Calcutta. He has extensive field experience in direct clinical delivery, strengthening public health surveillance systems and implementing health information systems in resource limited-settings.

Oommen served as the deputy research coordinator at Leprosy Mission in India leading research that informed the strategy around Leprosy elimination.

He served with the WHO at the India Country office and South East Asia Regional Office in the area of vaccine research, immunisation systems strengthening, implementing the Measles Aerosol Vaccine Development Project and establishment of a case based measles surveillance in India.

He is a Fellow of the International Academy of Health Sciences Informatics, a member of the WHO Digital Health Guidelines Development Group. He is the secretary of the Asia Pacific Association for Medical Informatics and serves on the International Advisory Board of the Commonwealth Centre for Digital Health as well as the Scientific Advisory Committee at the Foundation for Innovative Diagnostics, Geneva.

Oommen is currently a Senior Research fellow at The George Institute for global health India and leads research on role of health innovations in improving clinical outcomes in non-communicable diseases. He is a Professor at the Prasanna School of Public Health, Manipal Academy of Higher Education, India.