COVID-19, HIV, and Hepatitis C are among some of the deadliest communicable diseases that humans have ever faced. Historically, they have been responsible for millions of deaths and cases of chronic disease. Naturally, this begs the question of how health care professionals have managed to keep communicable diseases in check over the years, which is where the field of epidemiology illustrates its value.
Epidemiology and public health are directly related to one another. According to the Centers for Disease Control and Prevention, epidemiology is the study of how viruses and diseases are distributed and their main determinants. It is also the application of scientific methods that control communicable diseases and other health risks, which is what ensures the well-being of the public.
Although there are several types of epidemiologists, all of them focus on research and efforts to control the spread of diseases and other public health risks. Those who are considering public health career options are encouraged to pursue an applicable educational path, such as USC’s online Master of Public Health advanced degree program.
Types of Epidemiology at a Glance
Epidemiology is a branch of public health sciences dedicated to the study of disease and other health risks that affect different populations. What makes epidemiology distinct is that entire populations are collectively viewed as a patient. When a disease outbreak is detected, epidemiologists consider the town, county, or city as one collective group case.
Another attribute that makes epidemiology distinct is the broad range of public health problems that are tracked and investigated. Although epidemiology is most closely associated with research pertaining to infectious diseases, there are several types of epidemiology that focus on:
- Foodborne illnesses caused by parasites, toxins, bacteria, or viruses
- Environmental health risks caused by air pollutants, heavy metals, or lead
- Non-disease-related injuries, such as domestic violence and localized homicides
- Noninfectious diseases, such as birth defects and specific types of cancers
- Natural disasters, such as earthquakes and hurricanes
- Acts of terrorism that affect a specific demographic or region
By investigating the patterns and causes of public health risks and diseases, data is used to inform a plan that will mitigate the spread and deliver health care resources to populations who need them most. The data points most relevant to epidemiology include:
- Determinants: The factors that cause a disease or health risk to occur. Knowing the determinants informs the “how” and the “why” of public health risks. For instance, epidemiologists could determine that a train derailment resulting in harmful chemicals being spilled near a populated area is the source of subsequent public health issues.
- Health-related events or statuses: The factors related to health that can be linked back to behavior, genetic factors or external factors. For instance, obesity is not a communicable disease, but it is known to increase the risk of developing type 2 diabetes.
- Affected populations: The demographic, group or region that is affected by a disease or other public health risk. While a clinician considers one individual as a single patient, an epidemiologist may consider an entire neighborhood as one patient.
- Level of disease: This metric refers to the amount of a particular public health risk. “Endemic” means that there is a constant presence or normal amount of the disease within a geographic area. “Hyperendemic” means that there are persistent, increased levels of a disease within a population. “Epidemics” are defined as events where a public health risk has significantly spread and infected numerous populations. “Pandemics” are epidemics that have spread across several countries or continents, such as COVID-19.
What’s common among the many types of epidemiologists is that their findings can be used to understand public health risks and inform the policies intended to control and prevent them. The day-to-day responsibilities of an epidemiologist may vary depending on their specialty or area of focus.
Epidemiologists may specialize in public health areas such as chronic diseases, infectious diseases, environmental health, genetic epidemiology, natural disasters, mental health conditions, and more.
The following are some of the most common duties that epidemiologists perform:
- Gathering information about public health risks via observations, surveys, and interviews
- Developing studies to gain a better understanding of public health risks
- Analyzing results from studies and looking for meaningful insights and patterns
- Assisting in the development of public health policies that are informed by data
- Developing ways to improve current public health policies
- Communicating findings and recommendations to public health and government officials
- Assisting with public health initiatives and community outreach programs
- Supervising entry-level data analysts and researchers
Types of Epidemiologists
In a broad sense, the field of epidemiology focuses on tracking and collecting data pertaining to a range of public health threats. However, the field includes several different types of epidemiologists that either have a particular area of focus or a specialized set of skills and knowledge. Following are some of the different varieties of epidemiology careers.
Research Epidemiologist
Research epidemiologists study how diseases and viruses are transmitted and treated. Some of their typical job duties include developing and performing experiments, running tests and performing research on various drugs and countermeasures to public health risks. Research epidemiologists typically work in either a clinical setting or an academic setting — such as a university or college.
According to January 2023, data from Payscale, the average research epidemiologist makes approximately $99,400 per year.
Clinical Epidemiologist
Clinical epidemiologists study the frequency of diseases and how often they occur within specific populations. Ultimately, their research is used by medical professionals to mitigate disease outbreaks and promote the overall well-being of a population.
Some of their typical duties include collecting human samples to learn more about diseases, assisting with the development of preventive action plans, drawing correlations between infectious diseases and how they’re transmitted, gathering data about a population through surveys and interviews, and collaborating with a variety of health care professionals to develop more effective patient care solutions.
According to ZipRecruiter, clinical epidemiologists earn an annual average salary of $84,880.
Nurse Epidemiologist
Of all the different types of epidemiologists, a nurse epidemiologist is one of the few that specializes in delivering clinical care to patients. Using their advanced knowledge of communicable diseases, nurse epidemiologists work with patients who have been affected by viral, bacterial, fungal, or parasitic infections.
Some of their typical duties include assessing patients, evaluating infections, identifying the source of infections, working in collaboration with a medical team, developing quarantine protocols, implementing treatments, and educating health care staff on the correct procedures when dealing with outbreaks of diseases or viruses.
According to ZipRecruiter, the top 10% of nurse epidemiologists earn an average annual salary of $120,000 or more.
Public Health Epidemiology Doctor
A public health epidemiology doctor is a medical professional that specializes in epidemiology research. Professionals in this position need to have a Doctorate of Public Health (DrPH) to qualify. In this role, individuals typically focus on researching various transmissible, infectious and chronic diseases. However, some public health epidemiology doctors choose to focus on the clinical side. In those cases, they focus on treating patients and practicing medicine that relates to epidemiology.
Additionally, public health epidemiology doctors educate health care workers on how to identify and control various public health risks. They also advocate for public health services to be more accessible and raise awareness about common public health risks, such as the use of illegal substances, alcohol and tobacco.
According to the U.S. Bureau of Labor Statistics (BLS), epidemiologists who work in hospitals and medical facilities earn an average annual salary of $83,230 as of 2021.
Environmental Epidemiologist
Airborne toxins, spilled chemicals and pollution are just a few examples of environmental public health risks. Out of all the different types of epidemiologists, environmental epidemiologists are the only professionals who focus exclusively on environmental factors that can cause health care issues. They study the biological, chemical, and physical factors in the environment that can cause illness and disease.
Some of their duties include conducting public health surveillance, performing population analysis, developing and executing epidemiologic studies, and analyzing statistics that reveal patterns or useful insights.
According to the most recent information from Payscale, the average environmental epidemiologist makes approximately $57,300 per year.
Chronic Disease Epidemiologist
A chronic disease epidemiologist studies diseases that are ongoing such as Alzheimer's disease, diabetes, AIDS, and cancer. Their research aims to determine what causes these diseases, relevant trends, and how they affect public health. Chronic disease epidemiologists typically gather their data through surveillance, studies, and surveys, which can be used by medical professionals to develop treatments, cures, and other ways to mitigate chronic illnesses.
According to Glassdoor, the average annual salary for chronic disease epidemiologists is $88,113.
Applied Epidemiologist
Whereas epidemiology is focused on the study of diseases and public health risks, applied epidemiology puts the data and findings to good use. Applied epidemiologists communicate their data and insights to public health officials and the public, influence public health policies, evaluate health care services, develop effective treatments and interventions and use their data to make informed decisions. The practice of applied epidemiology is critical when determining resource allocation and which public health initiatives should be taken.
The BLS reports that the average epidemiologist made an annual median salary of $78,000 in 2021.
Epidemiology Investigator
There are usually several connecting threads between epidemiology and public health, and epidemiology investigators are part of the on-site team that aims to discover what those are. Epidemiology investigators specialize in performing assessments of populations that have a specific disease trend or chronic disease issue.
Some of their typical duties include collecting on-site samples, conducting environmental studies, interviewing members of the community, analyzing evidence and developing theories for the cause of public health risks and diseases.
According to Glassdoor, epidemiology investigators make an annual average of $102,748.
Disaster Epidemiologist
Disaster epidemiologists study the short-term and long-term health effects a disaster has on a population. The types of disasters include hurricanes, flooding, earthquakes, and other naturally occurring events that impact a large population. By studying disasters and how they affect public health, disaster epidemiologists can help guide emergency response protocols, develop effective recovery efforts, and even predict certain elements of future disasters, such as a hurricane’s expected category and sustained wind speed.
According to ZipRecruiter, the top 10% of disaster epidemiologists make an average annual salary of $115,000 or more.
Molecular Epidemiologist
The field of molecular epidemiology is relatively new. It combines the disciplines of epidemiology and molecular biology. Molecular epidemiologists study and gather data on diseases similar to epidemiologists; however, the difference is that they do this on a micro level, focusing on complex cells, gene relations, and proteins to understand diseases at a molecular level.
According to ZipRecruiter, the average annual salary for molecular epidemiologists is $92,302.
Field Epidemiologist
Out of all the different types of epidemiologists, field epidemiologists are most directly involved with the response to a public health risk that has the potential to impact a population. The primary function of a field epidemiologist is to guide the process of identifying the best solution and implement it to mitigate as many cases of illness and death as possible.
What differentiates field epidemiology from other types is that the public health scenarios are developing in real-time, which demands real-time decision-making. Field epidemiologists must make a judgment call when enough data or information about a public health risk is sufficient to take action.
According to ZipRecruiter, the top 10% of field epidemiologists earn an average annual salary of $166,500 or more.
Clinical Trial Research Epidemiologist
A clinical trial research epidemiologist uses the data and information that’s been collected to determine whether a medication or product will be effective against a specific disease. Although they can choose to focus on a range of diseases, their work typically pertains to studying heart disease and developing clinical trials that test the effectiveness of heart medications.
Clinical trial research epidemiologists usually work for pharmaceutical companies that develop medications that need to be tested. They may also work as members of medical groups dedicated to research.
According to the BLS, epidemiologists who specialize in scientific research and development earned approximately $126,500 annually in 2021.
Pharmaceutical Epidemiologist
Pharmaceutical epidemiologists study and measure the effects pharmaceutical drugs have on a specific demographic or population. They study prescription painkillers, Adderall, Xanax and other drugs that are prone to misuse. Further, they can monitor the use of specific prescription drugs by analyzing trends and social habits.
Once they have determined the main causes of substance misuse and how the demographic is responding to certain chemicals, they pass those findings to public health officials and the community.
There is currently no salary data available for the role of a pharmaceutical epidemiologist; however, the BLS reports that epidemiologists in scientific research and development services earned approximately $126,500 per year in 2021.
Supervisory Epidemiologist
Research labs and facilities typically have several epidemiologists in their employ. Supervisory epidemiologists are the individuals that oversee the day-to-day operations and manage a team of epidemiologists. In addition to guiding the direction of the research process, supervisory epidemiologists are critical to improving public health initiatives through their research.
They are usually the ones who assign epidemiologists certain tasks pertaining to data compilation and analytics about a specific disease. They are also responsible for ensuring that their team remains within compliance and follows regulations.
According to ZipRecruiter, managing epidemiologists earn an average annual salary of $107,632.
How to Become an Epidemiologist
The path to becoming an epidemiologist isn’t the same for everyone but typically involves earning an advanced degree, gaining sufficient experience, and — in some cases — earning certifications that are relevant to different types of epidemiology. Keeping that in mind, the following are some of the most critical steps to take when becoming an epidemiologist:
- Earning an undergraduate degree in either public health, nutrition, biostatistics, biology, or another relevant field. Additionally, undergraduate students should take coursework in behavioral science, social science, health science, calculus, chemistry, and biology.
- Earning a relevant advanced degree. Most epidemiologists earn either a Master of Science in Public Health (MSPH) or a Master of Public Health (MPH). While an MPH program is broad in focus, an MSPH degree program is intended for an epidemiologist who wants to focus on research.
- Earning a doctoral degree. This is an optional step for those who wish to work in academia as a professor or qualify for upper-level research positions.
- Completing an internship to gain on-the-job experience in epidemiology.
- Gaining additional experience in an entry-level position, as a study coordinator, research assistant or another similar role.
- Earning the Certified in Infection Control (CIC) certification. Although this is an optional step, the CIC certification demonstrates that an individual has specific skills and competencies pertaining to epidemiology that have been tested via examination, which may be beneficial for upward career movement. This certification is offered through the Certification Board of Infection Control and Epidemiology, Inc.
- After gaining enough experience and earning relevant credentials, individuals should update their resumes and apply for epidemiologist positions.
Epidemiology and Public Health: Improving Population Outcomes
The field of epidemiology is critical to ensuring positive population health outcomes in the face of communicable diseases and other public health threats. Considering that epidemiology and public health are so closely linked, epidemiologists guide the decision-making process and creation of health care policies with the data they uncover and the meaningful insights they find through analysis.
Many of the health care databases used in modern medicine are a direct result of work from epidemiologists. Having a large amount of reliable disease data over an expansive timeframe means that clinicians can make decisions that are firmly grounded in research. This means that the health care response to diseases such as Ebola, Hepatitis B, sexually transmitted infections, and shingles can be prompt as well as effective.
Additionally, the information and data collected by epidemiologists can be used to inform the public and contain outbreaks in localized areas. This is especially important with highly communicable diseases. When a disease or public health risk is effectively contained, it spares the rest of the population and prevents health care resources from being strained.
Finally, epidemiology can be used to eradicate diseases. Although smallpox and polio were once highly communicable diseases that affected large populations, research and the development of cures have nearly erased them from existence.
The Future of Epidemiology: Salary, Career Outlook and Innovation
Since diseases, viruses, infections and other forms of public health risks continue to materialize, the field of epidemiology must continue to evolve with them. Epidemiology has the potential to contribute to positive population health outcomes through innovation and specializations such as clinical trial research, biostatistics, and infectious disease preventative strategies.
Epidemiology is a field that continues to grow and has a demand for different types of epidemiologists. According to the BLS, the role of an epidemiologist is projected to grow by 26% by 2031. The BLS attributes the job growth to the need to replace epidemiologists that are retiring, exiting the labor force, or transferring to different occupations. Further, the BLS reports that epidemiologists made an annual median salary of $78,800 in 2021; however, those in the top 10% of earners made closer to $130,000 per year.
Additionally, different types of epidemiologists make different salaries. Different skill sets and areas of specialty may influence how much an epidemiologist gets paid. Education, experience, region, specialty, and other factors can also influence an epidemiologist’s salary. Those who aspire to reach senior-level roles in epidemiology are encouraged to pursue advanced education, such as a Master of Public Health degree.
Make a Positive Contribution to Public Health
Epidemiologists are critical in gathering data and information used to track diseases and public health threats, informing public health policy, and developing medications and mitigation strategies. The important contributions that epidemiologists make ensure that public health threats are appropriately addressed in a timely fashion and secure a positive shift in the population’s health and well-being.
Those who are interested in becoming part of the solution are encouraged to follow the appropriate educational path such as USC’s online Master of Public Health program. With five distinct concentrations, the program is designed to impart the most in-demand skills and knowledge that an epidemiologist will need to make a difference in the field. Learn more about the program so you can see how it will support your professional goals in epidemiology and public health.
Recommended Readings
How to Measure Air Pollution and Its Effects
What Is the Role of Public Health in a Humanitarian Crisis?
Example Sources
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American Public Health Association, Epidemiology
Centers for Disease Control and Prevention, Defining Field Epidemiology
Centers for Disease Control and Prevention, Disaster Epidemiology
Centers for Disease Control and Prevention, Lesson 1: Introduction to Epidemiology
Centers for Disease Control and Prevention, What is Epidemiology?
Certification Board of Infection Control and Epidemiology, Inc., CIC® Initial Certification FAQ
CSTE, “What Is Applied Epidemiology?”
Glassdoor, “How Much Does a Chronic Disease Epidemiologist Make?”
Glassdoor, “How Much Does an Epidemiology Investigator Make?”
Houston Chronicle, “Epidemiologist Certification”
Houston Chronicle, “What Are the Duties of an Epidemiologist?”
Indeed, “11 Epidemiologist Career Choices to Consider (With Tips)”
Indeed, “How to Become a Clinical Epidemiologist (With FAQs)”
Indeed, “How To Become a Nurse Epidemiologist (With Steps and Tips)”
Indeed, “How to Become an Epidemiologist in 6 Easy-to-Follow Steps”
Indeed, “What Does an Epidemiologist Do? (Duties, Salary and Skills)”
Indeed, “What Is a Public Health Epidemiology Doctor? (With Skills)”
National Institute of Allergy and Infectious Diseases, Career Pathways—Explore the Possibilities, Epidemiologist
Payscale, Average Environmental Epidemiologist Salary
Payscale, Average Epidemiologist Salary
Payscale, Average Research Epidemiologist Salary
Ready.gov, Pandemics
Science Museum, Epidemiology: The Public Health Science
The BMJ, “Chapter 1. What is Epidemiology?”
U.S. Bureau of Labor Statistics, Epidemiologists
ZipRecruiter, Clinical Epidemiologist Salary
ZipRecruiter, Disaster Epidemiologist Salary
ZipRecruiter, Field Epidemiology Salary
ZipRecruiter, Manager Epidemiology Salary
ZipRecruiter, Molecular Epidemiology Salary
ZipRecruiter, Nurse Epidemiologist Salary