The history of vaccines dates back farther than you might think. In 15th century China, doctors realized that patients who survived smallpox did not end up getting the disease again in the future. So, they began the practice of collecting smallpox scabs from people who had mild cases, drying them out, and grinding them into a powder to blow up the nostrils of healthy people in hopes of giving them immunity to the disease. While it’s difficult to say how effective this method was at promoting immunity, they were on the right track.
Advancements in the understanding of vaccines and immunity began to pick up in the late 19th century, with the discovery of vaccines for anthrax and rabies. Throughout the 20th century, scientists developed vaccines for whooping cough, diphtheria, tetanus, polio, measles, mumps, rubella, and chickenpox. Now, the number of people who die from preventable diseases has shrunk enormously, all thanks to vaccines.
However, in recent years, there has been a rise in anti-vaccine sentiment, which has contributed to outbreaks of preventable diseases in the United States and abroad, endangering public health. A Gallup poll from 2019 shows that only 84 percent of Americans think it’s “extremely” or “very” important to vaccinate their children, down from 94 percent in 2001. As a result, the World Health Organization (WHO) has listed vaccine hesitancy as a top global health challenge.
As the Covid-19 vaccine rolled out in early 2021, scientists had hoped to see 70 to 80 percent of the population vaccinated in order to achieve herd immunity. If 80 percent of a population is immune to a virus, four out of five people who come in contact with someone with that disease won’t get sick and contribute to the spread of the disease.
However, as of May 2022, the US had only achieved a 66.9 percent full vaccination rate. And that number has changed very little since the preceding months. With public opinion of the safety of the vaccine teetering and the number of people getting vaccinated seemingly stalled, scientists are concerned about achieving herd immunity.
Those who are undecided about whether or not they want to get vaccinated become crucial to achieving that percentage. Infectious disease expert and board-certified pathologist Dr. Guy Palmer says that there are three categories of people that qualify for the vaccine but are still unvaccinated: vaccine procrastinators, vaccine-hesitant, and the most staunch group, which has come to be known as anti-vaxxers. Those who are still on the fence about the decision may be concerned because of misinformation surrounding the safety of vaccines.
August is National Immunization Awareness Month, a time to educate the public on the importance of vaccinating people of all ages. “Misinformation and disinformation around the Covid vaccine have bled over into all the other lifespan vaccines from the ones children get when they’re born to ones that older folks get for pneumococcal and flu and shingles,” share Terri Burke, executive director of The Immunization Partnership.
While the Covid-19 vaccine is at the forefront, all vaccines remain crucial to individual and population health. In light of the pandemic, this message is more important than ever. So, we decided to talk to two experts to dispel the most common misconceptions about the safety of vaccines and learn how to get involved in vaccine advocacy.
Meet the Experts: Dr. Guy Palmer and Terri Burke
Guy Palmer DVM, PhD holds the Jan and Jack Creighton Endowed Chair at Washington State University where he is Regents Professor of Pathology and Infectious Diseases.
The founding director of WSU’s Paul G. Allen School for Global Animal Health, Dr. Palmer currently leads university-wide efforts as senior director of global health.
Terri Burke is the executive director for The Immunization Partnership based in League City, TX. This non-profit aims to eradicate vaccine-preventable diseases through community-based programs, advocacy, and supporting best practices.
Prior to her role at The Immunization Partnership, Burke was the executive director of the ACLU of Texas, a position she held for nearly 13 years. She studied journalism and political science at the University of Texas at Austin and received a bachelor of arts degree in political science from Lamar University. Notably, she had a long career as a journalist before moving into advocacy and activism.
Please note that Dr. Palmer was interviewed in 2021 and Burke in 2022.
Common Vaccine Criticism and Fears
“The folks who are vaccine-hesitant—some of them were hesitant before Covid-19—but misinformation campaigns really heightened those concerns and reservations about vaccines. So there’s a lot of education to be done,” shares Burke. Here are the top reasons why people may be hesitant to vaccinate.
Was the Covid-19 Vaccine Developed Too Quickly?
A major factor causing hesitancy toward the Covid-19 vaccine is the perception that the development process was rushed. It’s true that vaccines usually take at least a decade to develop, test, and manufacture. Both the chickenpox vaccine and FluMist took 28 years to develop. The human papillomavirus and the rotavirus vaccines each took 15 years. By comparison, the 11-month turnaround of the Covid-19 vaccine seems fast.
“We’ve heard repeatedly over the last year that this is an unprecedented development of a vaccine. Sure, one way to interpret it is to think they cut corners to get it out quickly, and that’s a pretty easy interpretation to make,” Dr. Palmer said.
“Well, you have to think about the fact that the first vaccine took us millions of years because we didn’t develop one until smallpox. And it was another hundred years until one was developed for rabies. Then it was about another a hundred years until we had the polio vaccines. But we’ve been getting better at this. So, the fact that we’ve got this out quickly is not really a surprise,” says Dr. Palmer.
Scientists also had a leg up in the case of Covid-19 because it belongs to the coronavirus family, which has been studied for 50 years. The so-called new mRNA technology used for the Covid-19 vaccine has actually been in development since the 1970s: “The reason they were able to bring the Covid-19 mRNA vaccine online so quickly is because of this long history of research that scientists were able to apply in a very quick way,” shares Burke.
So, despite the seemingly fast timeline, know that these vaccines went through all the appropriate clinical trials and the CDC continues to closely monitor them for safety and efficacy.
Can Vaccines Cause the Illness in Which They Aim to Prevent?
It is well-known that certain vaccines can lead to mild symptoms resembling the disease which they aim to protect against. One classic example is measles. The MMR vaccine contains a weakened (but live) measles virus that can cause a rash in about 5 percent of people. However, the vaccine does not cause the more serious symptoms associated with the disease, such as inflammation of the middle ear or the lung, or encephalitis (inflammation of the brain).
Indeed, vaccines don’t cause the full-blown disease because the virus or bacteria they contain have either been killed or weakened to the point that they don’t make you sick.
“Vaccines basically train your body to develop an immune response, similar to what would happen if you were to get the infection and recover from it,” Dr. Palmer said. “But they do so in a way that does not cause the infection because most vaccines use a very small piece of the virus. They don’t contain the rest of the components, so there’s no way it could cause disease.”
People may also confuse symptoms like nausea, fever, or drowsiness with the development of the disease against which they have been vaccinated. These are just normal reactions of the body to the vaccine, and they usually subside quickly. They are not connected to the disease against which you have been immunized.
Do Vaccines Contain Harmful Ingredients?
Another common source of fear surrounding vaccines is that they contain ingredients like mercury and aluminum. Let’s break down why these ingredients were used, if they still are, and whether or not they are dangerous.
“Previously, when you would take an inactive or killed part of the virus and use that as the vaccine, you needed to kind of stimulate the immune system to an additional degree,” Dr. Palmer said. “So there were certain ingredients put into those vaccines, different adjuncts, most of which aren’t present in modern vaccines.”
In 1999, the U.S. Public Health Service decided that as much mercury as possible should be removed from vaccines despite the fact that there is no evidence that the small amount used was dangerous. Today, no childhood vaccine in the U.S., except some formulations of flu vaccine in multi-dose vials, use the ingredient.
Aluminum-containing adjuvants (an ingredient used in some vaccines that helps to create a stronger immune response) have been used in vaccines since the 1930s and are still used today. Small amounts are added to help the body build stronger immunity against the germ in the vaccine. Scientific research has shown the amount of aluminum exposure in people who follow their recommended vaccine schedule is very low and is not readily absorbed by the body.
In sum, the ingredients used in modern vaccines are safe, but in rare cases, allergic reactions happen. In the case of the Covid-19 vaccine, experts say only about one in every 100,000 people has a severe allergic reaction.
The CDC’s website provides a full list of the ingredients contained in each of the Covid-19 vaccines if you’re curious to learn more.
Does the Covid Vaccine Alter Your DNA?
In the spring of 2020, when vaccines were still in trial stages, rumors on social media began to circulate that recipients’ DNA could be altered by vaccines. One video, in particular, made by osteopath Carrie Madej, gained traction for its claims that Covid-19 vaccines convert people into “genetically modified organisms.”
“This has been discussed quite a bit because both the Pfizer and the Moderna vaccines use something called an mRNA technique, but mRNA does not and can not change your genetic makeup,” Dr. Palmer explained. “That idea was kind of developed by people that don’t really understand what RNA is and how it works.”
The mRNA vaccines train the body’s cells to make a protein that creates an immune response, but the mRNA from a Covid-19 vaccine never enters the nucleus of the cell, where DNA is located. The mRNA is then broken down by the body. Therefore, it cannot affect or combine with our DNA to change our genetic code.
Do Vaccines Cause Autism?
One of the major drivers of vaccine skepticism, in general, is the belief that they can cause autism in children, which has been popularized by celebrities such as Jenny McCarthy.
“There’s this thinking that vaccines cause autism in children because after they get vaccinated, symptoms of autism begin to appear, therefore, they determine that one causes the other,” Dr. Palmer said.
Babies get their initial vaccines in their first few months of life to protect them from diseases or infections like polio, hepatitis B, and tetanus. Unrelatedly, the first symptoms of autism are observable in the first 12 months of life.
“It’s understandable why parents might come to this conclusion, but it’s just a wrong interpretation of cause and effect that builds from the frustration of the parents, which I’m very sympathetic to. However, there’s no connection.”
The idea comes from a 1998 paper by British physician and academic Dr. Andrew Wakefield and his colleagues who purported that the measles, mumps, and rubella (MMR) vaccine caused a loss of acquired skills in eight out of 12 children observed in the study.
“Actually, that paper was totally discredited and forced to be removed because it was fraudulent, but the myth still remains,” Dr. Palmer said. “But once you believe it, it’s pretty easy to just stick with it.”
Can the Vaccine Spread Covid?
Another popular conspiracy swirling on social media is the belief that the Covidf-19 virus can be spread through contact with someone that has been vaccinated—a concept known as “vaccine shedding.” This phenomenon was observed in rare cases with the oral polio vaccine of the 1950s when an individual came in contact with the feces of someone who had been vaccinated. However, vaccine shedding is not possible with the Covid-19 vaccine, Dr. Palmer explained.
“Polio vaccines are administered orally. The poliovirus replicates in the intestine and some of that can be shed through the feces and actually spread to other people. It does happen, but it’s very rare,” he said. “It doesn’t happen in the U.S. because we were no longer vaccinating routinely for polio. The way [the Covid-19 vaccine] is delivered is into your arm. There’s no way to shed it from there. It doesn’t go into your respiratory system.”
Get Involved With Vaccine Advocacy
National Immunization Month is an excellent time to get involved with vaccine advocacy: “It’s important to help people understand what happens if you don’t get vaccinated. Sure, smallpox has been eradicated and polio is exceedingly rare, so if you try to say, look, your kid could get polio, people are gonna shrug it off. But instead talk to them about things like pertussis, which still can happen. Explain how a child with pertussis is always gasping for breath, trying to suck in enough air to breathe. That is a powerful message,” says Burke.
She continues that there are many ways to get involved: “Look to your public health departments. Most of them will do something during that month, so make sure to take your kids to the festival or event where they’re going to be promoting vaccines,” she says. “Also, engage your neighbors on the sidewalk, or friends at church or synagogue and talk about vaccines. It is really important to stand up and say, I believe in vaccines and I believe and I believe that they work.”
Burke continues, “In the month of August, there will be lots of public service ads, posters, and flyers. So be sure to grab them and share.”
The Bottom Line: Vaccines are Effective and Safe
“Vaccines not only help to protect individuals, but they also protect society. We can live, we can work, we can worship, and we can play together when we are all protected,” says Burke.
While the common fears and criticisms about vaccines have been covered here, you are the one who can help make a difference. We hope that some of your questions have been answered and that you’ll share this article with friends and family members that may be concerned about the safety of vaccines.
Scientists had hoped to reach a threshold for herd immunity so that another outbreak of the Covid-19 virus could be avoided. However, now that is looking unlikely. Those who are still on the fence about the vaccine can still do their part and get vaccinated.
Visit Vaccines.gov to find a location near you for your initial series or booster. You can track the percentage of each state’s population with at least one dose of the vaccine, plus the percentage of people who are fully vaccinated, on the Mayo Clinic’s website.
Nina Chamlou
WriterNina Chamlou is an avid writer and multimedia content creator from Portland, OR. She writes about aviation, travel, business, technology, healthcare, and education. You can find her floating around the Pacific Northwest in diners and coffee shops, studying the locale from behind her MacBook.