In a year when it felt as though an avalanche of information overcame us every day, December 14, 2020, managed to stand apart. News alerts announced the first Pfizer-BioNTech vaccines were being administered locally and across the country. Within the same 24-hour period, phones everywhere pinged with the heartbreaking news that the United States had surpassed 300,000 coronavirus-related deaths, more than any other nation.

While many will remember that winter Monday for delivering a small dose of hope in a deeply unsettling year, the maiden COVID-19 vaccine wasn’t ever going to be a solution in and of itself. Politicized in the runup to the November election, developed on a breakneck timeline, and made  available through an emergency use authorization, the prophylactic still had to face public opinion. Surveys in November and December found that anywhere between 27 and 39 percent of American adults said they probably or definitely would not get inoculated. Early doses were redirected as even some health care workers opted out.

Immunizations, as we all know, are a complicated answer to what seems like a clear-cut question: How do we prevent the spread of infectious diseases? But since British physician Edward Jenner developed the world’s first modern vaccine in 1796—for smallpox—it has been made clear again and again that nothing about inoculations is straightforward.

This is not only because of the complexities involved in their creations, but also because of the fact that they require a certain threshold of people to get them in order to be effective. For COVID-19, experts say the required rate is around 70 to 80 percent of the U.S. population. That means the number of people who are considering not getting vaccinated is close to the cutoff for undermining herd immunity, which occurs when enough people are immune to a disease that continued spread is prevented. “Vaccines are a victim of their own success because they work, and so parents don’t see these diseases anymore that historically killed thousands or millions of children and, in some cases, adults as well,” says Dr. Sean O’Leary, a pediatric infectious disease specialist with Children’s Hospital Colorado and the University of Colorado School of Medicine. “We need to do everything we can to stop [this pandemic], and a vaccine is probably our best way for this to end.”

Not everyone agrees with that conclusion; in fact, Colorado is considered one of the country’s most vaccine-averse states. According to the Centers for Disease Control and Prevention, during the 2019-’20 school year Colorado had one of the lowest coverages in the country for MMR (measles, mumps, and rubella) vaccinations among kindergartners, at around 91 percent. In total, up to 10 percent of kids across the state have not received various school-required immunizations.

Some of their parents are part of a small but vocal bloc known as the medical freedom or health choice movement—made up of individuals who would never, or who are reluctant to, vaccinate their children and who advocate for their right to make that choice without government intervention. A little less than two percent of the U.S. population opts not to vaccinate at all, but between 25 and 40 percent of American parents say they have questions about vaccines or intentionally delay or skip specific immunizations. Public health officials refer to this group as “vaccine-hesitant.” “Those parents would not describe themselves as against vaccines; they just would say, ‘I don’t want them as they’re recommended, in combinations, at this age…,’ ” says Jennifer Reich, a sociology professor at the University of Colorado Denver who authored Calling the Shots: Why Parents Reject Vaccines. “It sounds different to the parents, but the result is the same, which is that children aren’t immunized and they’re not participating in community immunity, and they’re vulnerable to infectious diseases.”

It is this circumspect and undecided group that has been growing in recent years, according to national data, and questions about the efficacy and safety of the two U.S. authorized (at press time) COVID-19 vaccines have only added to its ranks. That expanding reluctance, paired with Colorado’s historical proclivity for renouncing inoculations, could complicate local health officials’ goals to put shots in millions of arms.

The shouting reverberated through the hearing room and wafted outside to the granite steps and lawn of the Colorado State Capitol. It was early June 2020, and hundreds of mostly maskless people were protesting Senate Bill 163, an effort originally introduced pre-pandemic that would streamline nonmedical vaccine exemptions and set a standard of 95 percent coverage for school-required vaccines. It was a significant enough fight that Robert Kennedy Jr., one of the country’s most prominent anti-vaccinators, made an appearance.

It’s not surprising that this skirmish would happen in Colorado. Many people point to the state’s pioneering spirit, libertarian streak, and (until recently) politically purple status as reasons why the medical freedom movement has found an eager audience here. “In general, Colorado has an approach that’s live and let live and don’t tell people how to live their lives—and that plays out in the vaccine debate,” says Toby Rogers, an economist and one of the country’s most outspoken—at least on Twitter—health choice advocates. Rogers, who lives in Southern California but was involved in the fight against SB 163, is among those who believe the MMR vaccine causes autism—a notion born from a now retracted 1998 study that helped launch the modern anti-vaccination sentiment but which has been disproven numerous times. Says Rogers: “Generally speaking, [Colorado’s] elected officials, at least historically, have been content to allow parents to make their own decisions.”

That remains the case. Although all 50 states allow for medical exemptions and the majority grant religious exemptions as well, the Centennial State remains one of the most permissive. It is one of just 15 states that allow for vaccine exemptions based on philosophical beliefs. Starting in 1978, Colorado parents who had personal, religious, or philosophical reasons for not vaccinating their children simply had to submit a signed form one time to their kids’ schools or licensed childcare facilities; in 2016 that became an annual requirement. Last year’s Senate Bill 163, which was signed into law in late June, combines all of the various nonmedical objections into a single exemption bucket; it also requires either a medical provider’s signature on the form or for parents to complete an evidence-based education module about vaccinating developed by the Colorado Department of Public Health & Environment (CDPHE).

Protesters rally against Senate Bill 163 at the Colorado State Capitol in June 2020. Photo courtesy of Helen H. Richardson/MediaNews Group/The Denver Post via Getty Images

Medical freedom advocates protested because they viewed the legislation as a step toward axing nonmedical exemptions altogether, which would have Colorado following in the footsteps of states like California, Maine, and Mississippi. “I think the concern right now is what’s next,” says Republican state Representative Dave Williams, who sponsored a separate Vaccine Consumer Protection Act bill that failed during the 2020 regular session. (Among other things, Williams’ legislation would have required patients under 18 to complete vaccination contraindication checklists and prohibited the recommendation or administration of a vaccine to a person younger than 18 without a parent or guardian’s consent.) “There are a lot of families out there that saw the passage of 163,” Williams says, “and they’re concerned that there’s going to be another rollback that chips away ever so slightly at the rights they enjoy now.”

Those involved in the bill’s crafting say the goal was to make the exemption process more rigorous, not to eradicate exemptions. “That’s not the intention,” says Stephanie Wasserman, executive director of Immunize Colorado, a nonprofit that works to protect Coloradans from vaccine-preventable diseases, and a supporter of the legislation. “The truth about Senate Bill 163 is it represented a unique Colorado solution, and we listened to stakeholders and the governor who said they didn’t want to get rid of the ability for parents to claim a nonmedical exemption. We came up with this compromise that’s driven by science and evidence.” Even if that’s the case, the clash of ideologies is providing a contentious backdrop for the current conversations surrounding COVID-19 vaccines, which Rogers calls the “[vaccine] debate on steroids.”

Gabriel Lockhart didn’t expect his first year as a “fully functioning adult doctor” to be spent in the chaos of a global pandemic. Following the completion of his fellowship in pulmonary critical care, he moved to Denver in July 2019 to take over as director of the intensive care unit at Saint Joseph Hospital. He traveled to New York City twice in spring 2020 to lend his expertise in the city’s overflowing ICUs.

Seeing what he’s seen and knowing what he knows, he’s frustrated by those who continue to downplay the seriousness of the pandemic or don’t wear masks or question the efficacy of vaccines. But he does empathize with that last group’s concerns: The pulmonologist and critical care intensivist, who is Black and Latino, knows firsthand the skepticism people of color, in particular, have for America’s health care system. “I have family members who are actively saying, ‘Oh, I’m not going to get the vaccine,’ ” Lockhart says. “My mother is one of them.”

Vaccine refusal or reluctance typically has been highest among white, college-educated, higher-income individuals—and those who adhere to a “natural” lifestyle—but experts are now seeing rising rates among lower-income and more conservative families. Hesitancy around the COVID-19 inoculations is also particularly acute among communities of color. Although they’ve been hardest hit by the pandemic—Black and Latino individuals are three times as likely as white people to become infected with the virus and two times more likely to die—they’re also among those most distrustful of the new vaccines. A fall 2020 survey by the CDPHE found that Black and Hispanic Coloradans were the least willing to be vaccinated, with only about 50 percent expressing interest. Much of that reluctance stems from a history of gross mistreatment and systemic racism by the U.S. health care establishment, from researchers in the mid-1900s purposely withholding effective care to Black men suffering from syphilis in what became known as the Tuskegee Experiment to the forced sterilization of one-third of females living in Puerto Rico between the 1930s and ’70s.

“There are legitimate concerns,” says Lockhart, who was vaccinated the first week Pfizer’s shot became available. “There are several examples of African Americans having worse outcomes within health care. That’s not to be ignored.” It’s why he joined the Colorado Vaccine Equity Taskforce. The 36-member group was established in the fall to provide communities of color—which make up roughly 29 percent of Colorado’s population—with facts about the vaccines in culturally competent ways and to counter predatory anti-vaccination misinformation campaigns they say the health choice movement is using to target those populations. The group has troubling new statistics to consider, too: As of January 24, state numbers showed that communities of color were receiving the vaccine at notably lower rates than white Coloradans. Says Lockhart: “All I can do is try to educate, try to inform, and have that come from a place of trying to help people who look like me and come from a similar background as me.”

The vaccine-resistant or -hesitant submit a variety of concerns. They take issue with specific immunizations, considering vaccines like the two-dose chickenpox inoculation unnecessary or wondering why their sons need to be protected against rubella, a mild infection that only has potentially serious repercussions for unborn babies. They believe too many shots are included on the current vaccine schedule, which includes roughly 15 (some requiring multiple doses) between birth and 18 years of age. They worry about potential side effects. They distrust Big Pharma or the U.S. health care system—or both.

In recent months, a significant number of Americans have said they simply want to wait and see how others respond to the first phases of the COVID-19 vaccine rollout. Side effects such as flulike symptoms, pain near the injection site, and the rare risk of anaphylaxis have also raised red flags, even among those who previously never objected to vaccinations. “Everybody has to make the decision for themselves. It’s not my place or anybody’s place to force somebody to take a vaccine,” says Dr. John Hammer, an infectious disease physician at Rose Medical Center. But, he adds, “if you look at the side effects of the vaccine and compare that to the potential effects of COVID-19, I think the vaccine is a hands-down winner.”

Hillary Rowenhorst sees things differently. The Boulder-area chiropractor has three unvaccinated kids under the age of six. “Fundamentally, it just doesn’t fit well with us, having researched all the vaccines,” she says of her family’s decision. “It doesn’t feel like they’re safe to me. The risk doesn’t outweigh the gain.”

Though uncommon, vaccine-caused injuries and deaths do occur. The National Vaccine Injury Compensation Program (NVICP) was established in the 1980s to address those outcomes. Between 2006 and 2018, health care professionals administered 3.7 billion doses of program-covered vaccines in the United States. Around 7,500 petitions—or 0.0002 percent—were adjudicated through that program during the same time period, and around 5,300 were compensated. The vast majority of reports to the NVICP describe minor reactions, like fevers; around 15 percent note more serious responses, including seizures.

Doctors and health officials acknowledge that vaccines, like any medical intervention, come with potential side effects, but they also say the likelihood of a severe reaction is so minute that any risks are far outweighed by the benefits vaccines create for society. Pam Long doesn’t agree with this so-called greater good argument. The president of the Colorado Health Choice Alliance, a nonprofit focused on informed consent and protecting vaccine exemptions and privacy around vaccine decisions, has a 17-year-old son who suffers from encephalopathy (in his case, chronic inflammation of the brain), resulting, she says, from the MMR vaccine he received at 15 months old.

Though Long says her son underwent lab tests to make that determination—and encephalitis is a qualifying injury under the NVICP—Children’s Hospital Colorado’s O’Leary notes the MMR vaccine has only been linked to a few cases of a specific form of encephalopathy called measles inclusion body encephalitis in severely immunocompromised patients. “When the question has been examined using large vaccine safety surveillance systems, they haven’t been able to detect an increased risk,” he says. However, for every 1,000 children who contract measles, one to three will develop encephalitis and 10 to 15 percent of those will die. “People in my situation—and I’m speaking for people who have had their child disabled from a vaccine—they do not value this social contract that people speak of, that I have some obligation to society when society has reneged on their obligation to me,” Long says. “There’s no drug that’s safe for every single person, but we’re pretending vaccines are, and that’s my root issue.”

The majority of Americans—more than 80 percent, in pre-pandemic surveys—support vaccinations, but there was a backslide during 2020 that concerns public health officials. During the first six months of the coronavirus crisis, 19 percent fewer childhood and adolescent vaccines were administered in Colorado; that trend occurred at the national level, too. The reasons for the decline are likely myriad—stay-at-home orders and worries about COVID-19 exposures in doctors’ offices could be partly to blame—but the consequences may be far-reaching, because having more unvaccinated kids impacts the immunity of entire communities. CU Denver’s Reich says many parents’ vaccine decisions are based on a risk-benefit analysis, and the COVID-19 shots are no different. “My impression is that people are making decisions about whether they think they’ll personally benefit from the vaccine and if they feel personally at risk of the infection,” she explains. “People’s calculations are not necessarily mathematically true, but they’re powerful in representing what they value and what they care about.”

They’re also prone to change over time. Confidence in the COVID-19 vaccines generally rose throughout 2020 as the inoculations went from hypothetical to real, as safety data became available, and as folks watched others receive the vaccine. Still, “choice” is the buzzword among medical freedom advocates who say they don’t want to stop others from getting vaccinated—including against COVID-19—but that they want the liberty to make private medical decisions. Nonvaccinating parents do “a lot of research on why we didn’t vaccinate, so we’re very aware of our choices and what could happen if they would get the disease,” Rowenhorst says. “Medical freedom needs to stay with parents…. I’m not willing to jeopardize my kids’ health.” No one in her family will get a COVID-19 shot. As with all vaccines, the irony, of course, is unvaccinated kids’ (and adults’) best hope for staying healthy is that enough other Coloradans line up to receive them. We’ll soon learn to what extent that happens.

This article was originally published in 5280 March 2021.
Daliah Singer
Daliah Singer
Daliah Singer is an award-winning writer and editor based in Denver. You can find more of her work at