But along with this question is often an undercurrent of confusion - and sometimes an openly voiced question - of what exactly public health is? I mean, I'm not training to be a doctor or a nurse. What do public health practitioners actually do?
The answer is...it's complicated.
Public health can mean nearly anything. If something has any tie to health, you can bet there are public health professionals working on it. Many public health professionals are also doctors and nurses. But many others, like me, are not.
In general, I explain public health this way. Traditional medical professionals are generally concerned with treating an individual once you get sick or engaging in proximal prevention at the individual level (when you walk through their doors, they can tell you to eat better foods or take a pill to keep your blood pressure down to prevent further issues). Public health, on the other hand, is typically concerned with preventing disease in the population at large (or in a group of folks) by affecting health further "upstream," ideally long before any symptoms related to disease emerge.
For example, whereas a doctor may refer you for a mammogram to catch breast cancer early, public health would investigate what is it that puts some groups of people at greater risk for breast cancer in the first place? And what is it that affects breast cancer outcomes beyond the biology of the disease?
For example, if a large group of individuals do not have insurance and therefore cannot access doctors, how does that change the outcomes for that group and others in similar situations? Further upstream still, if they do not have insurance, why? What circumstances are contributing to lower rates of insurance in certain communities compared to others? Also, are there any experiences in the population at large that can be changed to lower rates of breast cancer itself? For example, if eating certain foods might decrease risk, why is it that some groups eat those foods and others do not? What are the cultural norms around food? What is the availability and quality of produce in a neighborhood? What is the availability of disposable income and time for that group to invest in healthy eating? Or what types of chemicals are found in one location that are not found in another which might increase risk of cancer? How are these exposures unequally distributed across neighborhood, socioeconomic, racial, and other lines? Or what is it that leads to greater stress and thus greater risk for disease in one community compared to another?
And then public health might ask, now that we have answered these questions and know there are differences in experience for different groups, which lead to differences in disease outcomes (what we call "disparities"), what can we do to improve the average experiences and exposures of the populations who are not achieving optimal health?
The answers to that question can range from vaccination campaigns that broadly affect rates of infectious disease, to economic development initiatives that aim to improve overall conditions in a neighborhood, to policy changes that limit toxin-producing industries from concentrating in low income neighborhoods, to organizing communities to campaign for changes that matter to them. Public health interventions can be Medicaid expansion or quality improvement of the patient experience or violence prevention efforts or reducing stigma and increasing health care access for a particular group of people. Public health can mean creating school gardens to increase vegetable consumption or teaching sexual education to students to lower rates of STIs and unwanted pregnancies. Public health can involve educating the public about the benefits of breastfeeding or campaigning for a new farmer's market to increase access to fresh produce or removing lead from buildings frequented by children. It can mean encouraging exercise programs in schools or limiting advertisements of unhealthful products or requiring restaurant employees to wash their hands after using the restroom or campaigning for equitable housing rules. Public health can mean increasing employment opportunities or teaching stress management classes or passing stricter laws about elder care abuse or requiring safety precautions in factories or creating emergency preparedness plans.
And, well....you get the idea.
Public health can be almost anything that aims to prevent injury or disease and to decrease health disparities between groups. Public health also often involves research in how to do all of these things well and how effective our efforts really are at preventing disease anyway.