Those Nerdy Girls trust vaccines and are taking a moment to celebrate them in August, since it is National Immunization Awareness Month.
[Based on an original post by Nerdy Girl Megan Madsen written in August 2023.]
At Those Nerdy Girls, we argue that no breakthrough has been more important in keeping us healthy than the development of vaccines! Instead of hoping there is a treatment once someone gets sick *hint, there are not many treatments for infections caused by viruses* vaccines are given to prevent disease. During viral infection, often called natural infection, a virus or bacteria can make millions of copies of itself, start damaging the body, and cause illness before the immune system has a chance to deploy its defenses. Vaccines prepare the immune system by giving it instructions so it is ready to launch an attack on the invader right away instead of trying to play catch up after the virus gets in. This reduces the chance of illness or reduces the symptoms if someone does get sick.
The idea of preparing the immune system to prevent illness has been around for thousands of years. Most of our early efforts were to prevent smallpox. Smallpox was a highly contagious viral illness that had been killing around 1 in 3 people who became infected for over 3000 years. Those who were lucky enough to survive were often disfigured. Because it spread so easily and was so deadly, people were desperate for a way to stop smallpox. There are reports of people as far back as 200 BCE in Asia and Africa attempting to expose healthy people to tiny amounts of smallpox to prevent more severe illness. This was known as variolation because smallpox disease was caused by a virus named variola major. Lady Mary Wortley Montague brought variolation to Europe in 1721 after she observed the practice while living in Turkey. However, infection with the actual virus was and is extremely dangerous because it has the possibility of causing the actual disease. About 75 years later in 1796, the physician Edward Jenner used scientific and epidemiologic methods to make the connection that milkmaids who got cowpox, caused by a similar virus to smallpox, didn’t get sick with smallpox. The milkmaids got a very mild pox (not smallpox) infection. He hypothesized that material from a cowpox sore might protect against smallpox. This would be a way to protect against smallpox without risk of getting very ill. He tested this hypothesis on a child. He first injected the child with material from a cowpox sore, and then exposed the child to smallpox. Thank goodness his hypothesis was correct and the child didn’t get sick! While we would never try such a risky test today, from Jenner’s experiment, vaccination was born.
🚨Nerd alert: Vaccine comes from “vacca” meaning cow in Latin. Many immunologists and vaccine researchers call the process of injecting a vaccine and inducing an immune response “immunization”.
Not everyone was on board with Jenner’s new vaccination approach to prevent smallpox. Fear of the new science triggered silly rumors, including that the process could turn you into a cow. Eventually enough data was collected on the safety and effectiveness of the smallpox inoculation, causing the practice to spread across England and to France and the United States. As technology improved in the 1950s, the vaccine was produced in bigger, more stable, and safer quantities, resulting in widespread vaccination. In 1959, the World Health Organization called for a massive global effort in research, vaccine production and public health campaigning with a goal to end smallpox entirely. It took years of collaboration from scientists, vaccine makers, epidemiologists and governments all over the world, but in 1980 the World Health Organization declared global eradication of smallpox! That meant that there was not a single human in the world infected with smallpox anymore. In fact, there remains no smallpox virus in the world except two secure research locations, one in the US at the CDC, and one in Russia at the VECTOR laboratory. Eradication was a huge win for the world and an amazing example of the way public health campaigns can change our lives for the better.
On the tail of the success from the early work of the smallpox vaccine, research and development of vaccines to prevent other serious illnesses ramped up in the mid 1900s. Through the hard work of countless scientists, we saw the development of dozens vaccines, including:
💉 Yellow fever vaccine, 1938
💉 Pertussis (whooping cough) vaccine, 1939
💉 Influenza vaccine, 1945
💉 Polio vaccine, 1952-1955
💉 Measles vaccine, 1963
💉 Mumps vaccine, 1967
💉 Rubella vaccine, 1969
💉 Hepatitis B vaccine, 1969
💉 Combined measles, mumps, rubella vaccine 1971
💉 Pneumococcal vaccine, 1978
💉 Haemophilus influenzae type b (Hib) vaccine, 1985
💉 Rotavirus vaccine, 2006
💉 HPV vaccine, 2006
💉 Shingles vaccine, 2006, new updated 2017
💉 COVID-19 vaccine, 2020
💉 RSV vaccine, 2025
Many of these vaccines are part of a standard childhood immunization schedule recommended for all U.S. children. Childhood vaccinations have been integral in reducing illness and death on a scale that’s hard to comprehend in 2025. In 1900, the average person lived around 30 years, and nearly 1 in 3 babies died before the age of 1, mostly from infectious disease. Today it’s estimated that 4 million deaths worldwide are prevented each year [archived link] by childhood immunizations, and the average life expectancy is now closer to 75 in the US.
Scientists are always researching new ways to make vaccines better. In 2020, the mRNA vaccine for COVID showed just how effective new technologies could be. These types of vaccines are our most cutting edge and effective vaccines that can be made quickly, the exact ones we need to prepare us for the next pandemic. Unfortunately, over 500 billion USD in research funds for mRNA vaccines was recently cancelled in the US.
It is important to remember that vaccines are not just for children. The Shingles and RSV vaccines are for older people, and it is recommended that everyone stay up-to-date on the tDAP vaccine, especially if they are pregnant, and should consider annual vaccines for Flu and COVID, if they are eligible.
In 2019 the World Health Organization declared vaccine hesitance one of the top 10 global threats to human health. Vaccine hesitancy is in the news all the time these days, and it will have consequences on people’s health by allowing preventable disease to make comebacks.
The bottom line is that Those Nerdy Girls trust in vaccines and celebrate the lives they have saved every day, not just during National Immunization Awareness month.
If you want to know more about vaccines, check out the other many posts from Those Nerdy Girls about specific vaccines and diseases they prevent.
Stay well,
Those Nerdy Girls
Estimates of lives saved each year with vaccines
CDC: Fast Facts on Global Immunization [archived link]
WHO: Vaccines and immunization
Estimates of lives saved with COVID vaccines
NIH: Global Estimates of Lives and Life-Years Saved by COVID-19 Vaccination During 2020-2024
