They are the backroom boys of disease control. Working behind the scenes, epidemiologists — or “disease detectives” as they are sometimes called — fight vicious epidemic attacks, be it dengue, chikungunya, bird flu or SARS. Unfortunately, their contribution in combating disease and controlling epidemics often goes unrecognised. “The tangible satisfaction associated with treating patients is missing in epidemiology and perhaps that accounts for the invisibility of the field,” says Dipika Sur, deputy director, division of epidemiology, National Institute of Cholera and Enteric Diseases (NICED), Calcutta.

An important component of public health, epidemiology has traditionally been neglected in developing countries where the focus is on treatment. Dr Debasish Halder, who is studying for a masters degree in applied epidemiology (MAE) at the National Institute of Epidemiology (NIE) in Chennai, agrees. “The political will has always been in favour of the curative part of medicine and not the preventive side,” he explains. However, with the outbreak of bird flu, dengue and the new disease on the block — chikungunya — the importance of the field is slowly being recognised. The government has woken up to the fact that since it does not have the infrastructure to treat the huge number of patients in case of an epidemic, it is smarter to employ epidemiologists who can trace the cause of the disease and control it at an early stage. “Epidemiology has received a big boost with the government creating separate posts for preventive medicine,” says Sur.

In fact, all important discoveries in the field of public health have been due to detailed epidemiological analyses of events and diseases, claims Dr Sampath K. Krishnan, cluster head of communicable diseases and disease surveillance, office of the World Health Organisation representative to India, New Delhi. The significant contributions of this field include the eradication of smallpox from the world, and the near eradication or elimination of diseases like polio. The identification of the link between smoking and lung cancer has also been due to the efforts of epidemiologists.

So what does epidemiology involve? Says Dr Vikrant Sahasrabuddhe, assistant professor, Institute for Global Health, Vanderbilt University School of Medicine, Nashville, US, “A basic science in the field of public health, epidemiology deals with the study of the patterns and the causes of diseases in the population.” The data the epidemiologists collect — and interpret — are essential for the management, evaluation and planning of services for the prevention, control and treatment of disease.

Says Krishnan, “Epidemiology has emerged as the most important field in public health since it cross-cuts into almost all areas.”

Epidemiology is a very challenging field and it can be a very rewarding career too. Says Dr Subhashis Saha, district surveillance officer in North 24-Parganas, “I was appalled by the primary health conditions and the attitude shown towards development. That’s when I decided to pursue the MAE offered by the National Institute of Epidemiology.” The interesting component of these courses is the associated field work. Only three months of the two-year course is devoted to classroom teaching. The rest is devoted to live projects. The latest and the most successful example of the intervention by epidemiologists has been at Baduria to control chikungunya.

“In India, epidemiologists have traditionally been MBBS graduates who specialised in preventive medicine,” says Sahasrabuddhe who is currently in India to launch a clinical epidemiology research project. However, the field of public health is now coming into its own. Postgraduate courses in public health are now being offered by both government and private institutions. Some of the important institutes are the National Institute for Communicable Disease in Delhi, the National Institute of Epidemiology in Chennai, and the All India Institute for Hygiene and Public Health in Calcutta.

Most of these courses are open to MBBS graduates. Doctors can also do their postgraduate degrees in preventive and social medicine or community medicine or do a diploma in public health to specialise as epidemiologists. The sub-disciplines of epidemiology offer scope for further specialisations. These include infectious disease epidemiology, chronic disease epidemiology, environmental epidemiology, behavioural epidemiology, occupational epidemiology, and molecular epidemiology.

Epidemiologists are employed by the government as health officers at municipal corporations and also by NGOs, international agencies like the UNICEF and WHO. They also work at research institutions and universities. The remuneration depends on the type of organisation one works for but, on an average, you can expect to make Rs 30,000 to Rs 35,000 a month if employed by the government and anything between Rs 50,000 and Rs 1 lakh if in organisations like the WHO and UNICEF.

However, epidemiology is a tough discipline to pursue. An inquisitive and analytical mind as well as close attention to minute details are the pre-requisites for success. Says Dr D.K. Raut, head of the department, epidemiology, All India Institute of Hygiene and Public Health, Calcutta, “You need to have the skills of a detective to smell out the disease.”

On the flip side, epidemiologists have little time for anything except work and must travel a lot. It can also prove to be a risky occupation while investigating unknown diseases. But if you are committed, go for it. Detecting disease never looked more exciting in India.