Pandemics have been a thorn in the side of humanity for thousands of years.
But despite COVID-19 being the latest iteration in these deadly infectious diseases to strike, we are experiencing it in a very different public health context than past pandemics throughout history.
A New Era of Medicine
Since the onset of the 1918 influenza pandemic, humans have seen a monumental and undeniable leap forward in the health sciences.
Advancements in everything from sanitation to pharmacology have spread globally, resulting in a health landscape that is almost unrecognizable from those during past disease outbreaks.
While it’s not possible to demonstrate every life-saving advancement in medical knowledge in just one chart, the rise of life expectancy at birth can be a useful proxy. In just 65 years, modern medicine has propelled countries around the world to see a rapid surge in this crucial measure:
The above animation, which comes to us from Reddit user u/karthikvcp, provides a helpful reminder of just how much has changed in public health over recent decades.
And although countries seem to move up following a linear line, here’s another look at this surge in global life expectancy on a much longer timeline — since the dawn of human civilization:
Yes, for most of human history, it’s been estimated that global life expectancy at birth has bounced between 20 and 30 years.
Beginning approximately in the year 1820, global life expectancy started its exponential ascent, seeing its most impressive gains after 1950 as modern sanitation and medical advancements began to trickle down to developing nations.
Life Expectancy: Interactive Version
While the 13-second animation is a fast summation of the revolution that has occurred in public health, here’s an interactive version from Our World in Data that plots the exact same data:
Still at the Mercy of Nature
Although our understandings of epidemiology and disease treatment are better than they’ve been during previous pandemics, other aspects of modern society have still compounded to make COVID-19 a complex challenge for public health officials.
Population density, frequency of travel, and a modern tendency to gather in large groups are all factors that have contributed to an initial spread of the virus that was faster and more widespread than anything humanity has ever seen.
And so, even with our increased level of medical sophistication, it seems we are still at the mercy of Mother Nature — just in a very different set of circumstances than in pandemics past.
Charted: Healthcare Spending and Life Expectancy, by Country
This graphic looks at average life expectancies in countries around the world, compared to each country’s healthcare spending per capita.
Charted: Healthcare Spending and Life Expectancy, by Country
Over the last century, life expectancy at birth has more than doubled across the globe, largely thanks to innovations and discoveries in various medical fields around sanitation, vaccines, and preventative healthcare.
Yet, while the average life expectancy for humans has increased significantly on a global scale, there’s still a noticeable gap in average life expectancies between different countries.
What’s the explanation for this divide? According to World Bank data compiled by Truman Du, it may be partially related to the amount of money a country spends on its healthcare.
More Spending Generally Means More Years
The latest available data from the World Bank includes both the healthcare spending per capita of 178 different countries and their average life expectancy.
Perhaps unsurprisingly, the analysis found that countries that spent more on healthcare tended to have higher average life expectancies up until reaching the 80-year mark.
|Country||Health expenditure per capita (USD, 2019)||Life expectancy at birth, total (years, 2020)|
|United Arab Emirates||$1,843||78|
|Bosnia and Herzegovina||$554||78|
|Antigua and Barbuda||$760||77|
|Iran, Islamic Rep.||$470||77|
|Trinidad and Tobago||$1,168||74|
|St. Vincent and the Grenadines||$355||73|
|Egypt, Arab Rep.||$150||72|
|Sao Tome and Principe||$108||71|
|Papua New Guinea||$65||65|
|Congo, Dem. Rep.||$21||61|
However, there were a few slight exceptions. For instance, while the United States has the largest spending of any country included in the dataset, its average life expectancy of 77 years is lower than many other countries that spend far less per capita.
What’s going on in the United States? While there are several intermingling factors at play, some researchers believe a big contributor is the country’s higher infant mortality rate, along with its higher relative rate of violence among young adults.
On the other end of the spectrum, Japan, Singapore, and South Korea have the highest life expectancies on the list despite their relatively low spending per capita.
It’s worth mentioning that this wasn’t always the case—in the 1960s, Japan’s life expectancy was actually the lowest among the G7 countries, and South Korea’s was below 60 years, making it one of the top 30 countries by improved life expectancy:
View the full-size infographic
In fact, the last 60 years have seen many countries substantially increase their average life expectancies from the 30-40 year range to 70+ years. But as the header chart shows, there are still many countries lagging behind in Africa, Asia, and Oceania.
How High Can Average Life Expectancy Go?
Since people are living longer than they’ve ever lived before, how much higher will average life expectancies be in another 100 years?
Recent research published in Nature Communications suggests that, under the right circumstances, human beings have the potential to live up to 150 years.
Projections from the UN predict that growth will be divided, with developed countries seeing higher life expectancies than developing regions.
However, as seen in the above chart from the World Economic Forum and using UN data, it’s likely the gap between developed and developing countries will narrow over time.
Visualizing the Composition of Blood
Despite its simple appearance, blood is made up of many microscopic elements. This infographic visualizes the composition of blood.
The Composition of Blood
Have you ever wondered what blood is made up of?
With the average adult possessing five to six liters of blood in the body, this fluid is vital to our lives, circulating oxygen through the body and serving many different functions.
Despite its simple, deep-red appearance, blood is comprised of many tiny chemical components. This infographic visualizes the composition of blood and the microscopic contents in it.
What is Blood Made Up Of?
There are two main components that comprise blood:
- Plasma – 55%
Plasma is the fluid or aqueous part of blood, making up more than half of blood content.
- Formed elements – 45%
Formed elements refer to the cells, platelets, and cell fragments that are suspended in the plasma.
Plasma is primarily made up of water (91%), salts, and enzymes, but it also carries important proteins and components that serve many bodily functions.
Plasma proteins make up 7% of plasma contents and are created in the liver. These include:
These proteins keep fluids from leaking out of blood vessels into other parts of the body. They also transport important molecules like calcium and help neutralize toxins.
These play an important role in clotting blood and fighting infections and are also transporters of hormones, minerals, and fats.
- Fibrinogen and Prothrombin
Both of these proteins help stop bleeding by facilitating the creation of blood clots during wound-healing.
Water and proteins make up 98% of plasma in blood. The other 2% is made up of small traces of chemical byproducts and cellular waste, including electrolytes, glucose, and other nutrients.
There are three categories of formed elements in blood: platelets, white blood cells, and red blood cells. Red blood cells make up 99% of formed elements, with the other 1% comprised of platelets and white blood cells.
- Platelets (Thrombocytes)
Platelets are cells from the immune system with the primary function of forming clots to reduce bleeding from wounds. This makes them critical not only for small wounds like cuts but also for surgeries and traumatic injuries.
- White blood cells (Leukocytes)
White blood cells protect our bodies from infection. There are five types of white blood cells with different roles in fighting infections: some attack foreign cells and viruses, some produce antibodies, some clean up dead cells, and some respond to allergens.
- Red blood cells (Erythrocytes)
Red blood cells deliver fresh oxygen and nutrients all over the body. They contain a special protein called hemoglobin, which carries oxygen and gives blood its bright red color.
The lifespan of a typical red blood cell is around 120 days, after which it dies and is replaced by a new cell. Our bodies are constantly producing red blood cells in the bone marrow, at a rate of millions of cells per second.
Abnormal Red Blood Cells
Normal red blood cells are round, flattened disks that are thinner in the middle. However, certain diseases and medical therapies can change the shape of red blood cells in different ways.
Here are the types of abnormal red blood cells and their associated diseases:
Sickle cell anemia is a well-known disease that affects the shape of red blood cells. Unlike normal, round red blood cells, cells associated with sickle cell disease are crescent- or sickle-shaped, which can slow and block blood flow.
Other common causes of abnormally shaped red blood cells are thalassemia, hereditary blood disorders, iron deficiency anemia, and liver disease. Identifying abnormal blood cells plays an important role in diagnosing the underlying causes and in finding treatments.
The Functions of Blood
We know that blood is vital, but what does it actually do in the body?
For starters, here are some of the functions of blood:
- Blood transports oxygen to different parts of the body, providing an energy source. It also delivers carbon dioxide to the lungs for exhalation.
- The platelets, white blood cells, and plasma proteins in blood play an important role in fighting infections and clotting.
- Blood transports the body’s waste products to the kidneys and liver, which filter it and recirculate clean blood.
- Blood helps regulate the body’s internal temperature by absorbing and distributing heat throughout the body.
While we all know that we can’t live without blood, it serves many different functions in the body that we often don’t notice. For humans and many other organisms alike, blood is an integral component that keeps us alive and going.
Personal Finance7 days ago
Ranked: The Best Countries to Retire In
Demographics4 weeks ago
Ranked: Gen Z’s Favorite Brands, Compared with Older Generations
Technology3 weeks ago
The Shrinking Trillion Dollar Market Cap Club
Markets2 weeks ago
Visualized: FTX’s Leaked Balance Sheet
Technology1 week ago
Visualizing the World’s Top Social Media and Messaging Apps
Politics4 weeks ago
Visualized: The Biggest Donors of the 2022 U.S. Midterm Elections
Misc3 weeks ago
Visualizing the Evolution of Vision and the Eye
Money3 weeks ago
The U.S. and China Account for Half the World’s Household Wealth