In 1848, an outbreak of typhus  was ravaging Upper Silesia,   a poor, rural community in what’s now considered  modern-day Poland.

Today, we know that typhus is   a bacterial disease spread through contact with  infected body lice. But back then, we mostly just   knew that it was killing a lot of people.

To learn more about the disease’s spread,   government officials sent a bright, young German  pathologist named Rudolf Virchow to investigate.   In a 290-page report detailing his findings,  Virchow came to a groundbreaking conclusion. He proposed that there was a strong  connection between the spread of disease   in the region and the poor social  conditions in which people lived. Today, we’re going to break down every  single page of Virchow’s report and– Oh, what’s that?

We’re just doing  two sentences? Thank goodness. Virchow wrote that, “If medicine is to  fulfill her greatest task, then she must  enter the political and social life.

Do  we not always find the diseases of the   populace traceable to defects in society?” Okay, translation: When it comes to when   and how we maintain our health,  society is kind of a big deal. And today, we’re going to take a look at  exactly what defects in our society Virchow   was talking about. Turns out, these defects are  connected to the social determinants of health,   and they are deeply connected to one another.

Hi, I’m Vanessa Hill, and this  is Crash Course Public Health! INTRO I want to note up top, for the purposes  of this episode, we’ll stick with the   basics of this incredibly complex topic. So let’s start here: we exist in a society.

Over at Crash Course Sociology, we define  society as “a group of people who share a   culture and a territory.” Everything  we do, we do in our society. We shop,   date, and bathe in society. And in general, society has also done a lot to improve our health, by making  things like sanitation, healthy foods,   and affordable housing more available.

Improvements like these are a big part of why   global life expectancy has increased so much over  the last few centuries. Like up until around 1800,   the vast majority of people on Earth lived in  poverty, and infant mortality was extremely high.   Overall, not a single country had an  average life expectancy over 40 years. But as we got better at building societies,  we got better at helping people live longer.   As of 2019, the United Nations estimates that the  average global life expectancy is over 72 years.

Though we should note that was pre-Covid. And life expectancy hasn’t increased  the same way in every society. While society-level improvements can improve  the health of the general population,   they don’t always do this equally.  The impact of these improvements   often varies according to things like race,  ethnicity, class, gender, and disability.

To understand why, we need to start by looking  at the living and working conditions in which   we spend our time – and which impact our health.  We call these the social determinants of health. Now, some of the social determinants  of health might feel pretty obvious.   Like, we don’t need to be a discerning,  19th-century German physician to know that   a society without access to food probably  isn’t going to be a society for very long. But just because a society has food doesn’t mean  that equal access to healthy foods is a given.   A food desert is a neighborhood without easy  access to fresh foods like fruits and vegetables.   Rather than fully-stocked grocery stores,  residents in these neighborhoods might have   to rely on convenience stores, gas  stations, and fast food restaurants.

The lack of consistent  access to enough affordable,   healthy food in places like food deserts is called food insecurity. It could be difficult to access food because  it’s physically far away. For example,   developers may be less incentivized  to build fully-stocked supermarkets in low-income communities where people  have less money to spend in stores,  making the nearest grocery store  a long bus or car ride away.

But healthy food may be hard to access  because it’s just too expensive.  A survey of 11 Southern African cities by  the African Food Security Urban Network   found that even in poor neighborhoods  where food is physically nearby,   on average, 57% of families in these neighborhoods  still reported limited access to healthy food. This suggests that the problem isn’t  always a matter of distance or convenience. Sometimes, food is just so expensive that the  cost prohibits families from accessing it!

And while we’re discussing food,   we might as well talk about another  element of Survival 101: shelter. Stable housing is a foundation for good health.  Evidence suggests that people who experience housing instability - like being  behind on their rent or mortgage,   moving for cost reasons, eviction, or  experiencing homelessness - are more   likely to self-rate their health as poor and are  more likely to experience depression and anxiety.   These experiences are stressful, and  data suggests that this stress is   partly responsible for the relationship  between housing instability and health. Like food and shelter, being able to  regularly and reliably access health services,   like a doctor or pharmacy, is key to preventing  disease, treating health conditions, and reducing   the likelihood that we die early.

So, public  health experts consider access to health care   to be another key social determinant of health. Much like life expectancy, in the grand scheme   of human history, health care has sort of  never been better than it is right now. Innovations in science and medicine mean that we should be better  at managing and curing disease than ever before.

But, like with the other  improvements we’ve discussed, we haven’t managed to make these  advancements accessible to everyone. For one thing, to receive health care,  we need to transport our bodies to a   place where our health can be, well, cared  for. Yet every year in the United States,   around 3.6 million people don’t receive medical  care just because of transportation issues.

Like with food deserts, these issues  might arise because of distance.   Some of us live in rural areas far from  the nearest hospital. But even in cities,   things like traffic or an unreliable public  transportation system with multiple transfers   can require time that a lot of us just  don’t have to get to appointments. And it’s not enough to just get to a healthcare  provider.

We also need to be able to afford care.   Access to affordable and quality  insurance reduces barriers to health   care by reducing the cost of check-ups,  treatment, and medicine. It also makes us   more likely to visit a doctor for preventive care  and less likely to delay care when we’re unwell,   practices which are linked to better health. For example, studies in Indonesia and Ghana   have shown that access to health insurance was  strongly associated with pregnant women getting   check-ups throughout their pregnancy, which  allowed prevention and diagnosis of potential   problems early on in the pregnancy.

And without  insurance, we’re less likely to get to a doctor   and to experience those benefits. And so long as we’re talking about   costs, nothing tells the story quite like money. Take income, or how much money a household makes.   In the United States, the gap in life expectancy  between the richest and poorest people   is 10 years for women and 14 years for men.

Another financial factor that contributes   to our health is our wealth. While income  is the new money we earn from things like   our work and investments, wealth is the  total value of all the stuff that we own,   from the money in our bank account to our real  estate. Whether it’s our income or our wealth,   money is one of the keys to unlocking all those  social determinants we’ve been talking about.

And when it comes to making money,  it certainly helps to have access to   quality education. Almost universally,  improvements in countries’ education   systems have been linked to increases in their  average household income. Plus, level of education   can also affect the way we feel in healthcare  environments.

Education can give us the tools,   skills, and even the confidence we need to  navigate complicated things like healthcare. So while, say, a college grad with a science  background might feel more comfortable   talking about treatment options with a doctor,  someone without that academic background  might feel awkward or anxious. That may seem like a small difference,   but it can impact how frequently we  receive check-ups and preventive care   which, over time, can make a  big difference in our health.  Education also plays a major  role in our occupation,  or the kind of work we do, and we generally  assign a social status to that work.

Like, we might say that a suited-up hedge fund  manager at a bank has a high occupational status.   But then there’s the bank’s summer intern whose  biggest responsibility is to deliver the hedge   fund manager her afternoon coffee exactly how  she likes it. And then there’s the barista   down the street who made that coffee. Their  occupational status would probably be lower.

And people with lower occupational status tend  to be more stressed, have worse health care,   and less freedom over how they spend their  time–all of which affects their health. But in life, and in public health, we don’t  measure people by their occupation alone. And   by now, we can see how all of the determinants  of health we’ve described so far are related.

Combining the measurements of  income, occupation, education,   and more helps to determine our socioeconomic  status. This basically tells us where we fall   in the grand hierarchy of our society.  It’s also one of the ways public health   experts group people together to better  understand health across different groups. But the world isn’t just  made up of Harvard-educated   bankers and coffee-brewing baristas.

Most of us fall somewhere in between–and   the details can be subjective. Let’s go to the Thought Bubble. Our story starts with two people  working at the Marsupial Research Lab   at the fictional Stancester University.

Our first person is Dr. Pouches, a young,  celebrated professor who is the world’s   leading expert on, I don’t know, wombats.  They’re the keynote speaker at the Global   Marsupial Convention, the face of Wombat  Weekly, and they’re generally considered to   be something of a wombat prodigy. Our second person is Burt,   a wombat sanitation worker who specializes  in cleaning up after the wombats in the lab.   Burt has a high school diploma, has received  special training for his role, and is working   on obtaining his laboratory animal technologist  certification, but he never went to college.

Based on education and occupation alone,   we, as outside observers, might think Dr.  Pouches has the higher socioeconomic status.  But, Dr. Pouches and Burt might  not rank themselves that way. Turns out that Dr.

Pouches is struggling to  get tenure at their university, while Burt has   a pretty steady gig. He makes a consistent yearly  salary, gets great benefits, and after a few years   on the job is even promoted to Assistant  Director of Marsupial Sanitation Affairs!  So, in a community where job security is highly valued, Burt may consider himself   in a pretty good socioeconomic  position, while Dr. Pouches may not.

But in an alternate scenario where Dr.  Pouches had tenure in the bag (or the pouch), plus the fame, clout, and upper hand in  hashtag-Marsupial Twitter arguments,   they may consider themself better off.  Thanks, Thought Bubble. So it’s, of course, never quite that simple.  There are many other factors, like race, religion,   and gender, that contribute to socioeconomic  status. But it’s clear that different societies,   communities, and individuals will weigh different  parts of our socioeconomic status differently.   And that can affect our access  to important health resources.

Understanding how and why societies and the people  living in them view those parts differently,   especially when it comes to our identities,  is all part of better understanding the   social determinants of health. Because at  Crash Course, we don’t just want to know   that something happens. We want to know  why, so maybe, we can make it better.

Join us next episode as we dig deeper into the  social determinants of health to figure out   exactly how they affect us–wombats or no wombats. Thanks for watching this episode  of Crash Course Public Health,   which was produced by Complexly in partnership  with the American Public Health Association.   If you want to learn even more about Public  Health, head over to APHA’s YouTube channel   to watch “That’s Public Health” a series  created by APHA and Complexly. Crash Course was filmed in the Castle  Geraghty studio in Indianapolis, IN,   and made with the help of all these curious  people.

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