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Why Study Epidemiology?

Epidemiology is the study of the causes, risks, incidences, and movement of diseases among populations. An epidemiologist analyzes patterns and other information relating to the development and spread of a disease or other health conditions. Governments and public health organizations use this analysis to plan their policies and to strategize against the spread of existing disease or the outbreak of future epidemics.

Sep 6, 2023
  • Education
Why Study Epidemiology?

Problem-solving is at the core of epidemiology. The process of analysis and response is powered by scientific method, collaboration, and co-operation. Epidemiology saves lives on a massive scale and has the power to reduce suffering significantly. But, as the diverse international response to coronavirus has shown, epidemiology cannot always provide clear answers. When it does, the communication to and interpretation of these answers by policy-makers is a matter of life and death for thousands or millions of people. It is essential for epidemiologists not only to draw accurate conclusions but to assess and present their findings as clearly and helpfully as possible.

If your science and research skills are first-rate, you have a strong sense of humanitarian responsibility, and you are looking for a career that is as challenging as it is rewarding, why not consider studying epidemiology.

What to study to become an epidemiologist

Budding epidemiologists commonly take one of two degree paths to pursue their ambition: epidemiology or public health. Most professionals have a master's in one of these subjects, while those that work in research often have a PhD. Some come to the discipline from a background in medicine.

Career advisors do not recommend any particular bachelor's to prepare for your master's. Still, a STEM major might be most helpful -- and some institutions are more specific about which subjects they will accept. Useful classes to take include behavioral science, biology, chemistry, social science, and statistics. To be accepted onto a good program, you will need evidence of your numeracy skills and preferably some experience in a health-related field.

Your master's should cover the essentials of epidemiology, including modules on statistics, clinical trial design, and ethics. Electives may include areas of statistics/analysis such as Bayesian statistics, demographic methods, or spatial analysis, and you may be able to weight your study towards an area such as cancer, genetic epidemiology, or tropical diseases. You will need to write a thesis.

To progress to an academic or senior-level research role, a PhD will be invaluable. You will probably have a good idea from your master's and your work experience just what you want to research and write about, but you will need to find a program that matches your interests and a department that can support your particular type of research.

DNA Genotyping and Sequencing. A technician loads DNA samples into a desktop genomic sequencing machine at the Cancer Genomics Research Laboratory, part of the National Cancer Institute's Division of Cancer Epidemiology and Genetics (DCEG). Creator:	Daniel Sone

Career paths

Broadly speaking, there are two types of epidemiologist. A research epidemiologist is mostly office-based as they work with statistics and model-building to identify the causes and patterns of diseases. A clinical epidemiologist is closer to the pathology of the disease, working directly with patients to understand how the illness develops. For this reason, clinical epidemiologists usually have medical qualifications.

Within these categories, you might work as an infection control epidemiologist, an applied epidemiologist, a disaster epidemiologist, a molecular epidemiologist, or any other role across a broad spectrum of specializations. Some roles are defined by the type of disease/outbreak with which they are concerned; others, by the nature and scope of the research that the epidemiologist pursues.

The day-to-day work of an epidemiologist revolves around “[r]eviewing and evaluating the rigor of scientific information,” says David H. Schwartz, PhD, Head of Scientific Support to Counsel for Innovative Science Solutions. “This includes the study design, conduct, and then the interpretation of the study findings. Ultimately, we need to align the evidence with the real-world problem and develop defensible arguments that are consistent with the scientific evidence.”

Epidemiology does not always take place in times of crisis, but the working week tends to be varied and can spill over into weekends and evenings. An ambitious epidemiologist also needs to keep up with their reading, of the latest academic material and the latest news, to follow developments in the field. Depending on your role, you may need to travel for conferences and research -- in the latter case, sometimes for extended periods in infectious settings.

But whatever your day-to-day work, you could be called to play a different role in a crisis. For example, during the outbreak of coronavirus along the east coast, the Florida Department of Health employed 100 university professors and students “to do what epidemiologists do: interview people with coronavirus about their history and symptoms, trace their contacts and enter that information into databases.

Epidemiologists work for national and international public health agencies and other governmental organizations. Some of the most famous are Médecins Sans Frontières (Doctors Without Borders), the World Health Organization (WHO), and the Centers for Disease Control and Prevention (CDC). Common destinations for epidemiology graduates include universities and pharmaceutical companies.

Salaries for epidemiologists start upwards of $30,000 and average out at around $70,000. Senior professionals may earn up to around $125,000 per year.

The skillset of an epidemiologist

An epidemiologist won’t get far simply analyzing data using long-established methods. New diseases and developing social conditions -- as well as new technologies -- command innovation and adaptation. Researchers must be able to carefully consider and define the terms of their analysis, and develop appropriate methods for compiling, processing, and analyzing data and other relevant types of information.

Flexibility like this requires an advanced understanding of statistics, logic, and critical thinking, on top of the ability to keep abreast of a broad range of research and contextual information. You will need to use specialist statistical software and mapping applications, and to back-up and explain your thinking in reports and presentations. You will need to communicate and collaborate with outside agencies and potentially with individual patients. Your planning and strategizing skills will be put to the test, as will your understanding of socio-political contexts and your sense of ethics.

In brief, the following skills are essential to a career in epidemiology:

  • Sharp general intelligence and emotional intelligence.
  • Logic and problem-solving skills.
  • Research skills, self-motivation, and the ability to juggle disparate pieces of information.
  • The ability to stay calm and focused under pressure.
  • Competency in math and statistics.
  • Being quick to learn new software and digital techniques.
  • Strong written and verbal communication skills.
  • Good at listening, and working alone and in a team.

The future of epidemiology

It would be great to live in a world without disease but, because this is impossible, we will always need epidemiology. However, the nature of the job is evolving all the time. The ability that epidemiologists have to suppress and eradicate existing diseases is growing stronger. For example, the development of big data empowers researchers to trace patterns of human behavior at a previously unimaginable scale. Communication technologies allow for faster, more meaningful initiatives on a broader international platform. And advances in genetic mapping open the door to methodologies that would have seemed like science-fiction a few decades ago! So, if you desire a healthier, safer future for mankind, a career in epidemiology will help you become part of the solution to one of humanity's most enduring problems.