In the aftermath of the Covid-19 pandemic, the topic of vaccination has become a contentious issue in the United States, particularly with the emergence of health secretary Robert F. Kennedy Jr. The debate centers on the value of individual choice and “medical freedom” in deciding which vaccines to receive and when to receive them.
This focus on personal choice has significant implications for public health, impacting everyone.
Experts highlight that many vaccines offer indirect benefits, or knock-on effects, when widely administered, benefiting both individuals and the broader community. For example, the human papillomavirus (HPV) vaccine has reduced cancer rates in both women and men, even in regions where only girls are primarily vaccinated.
However, not everyone acknowledges or appreciates these broader benefits. Vaccine critics, many of whom grew up without experiencing diseases eradicated by vaccines, often focus on perceived safety risks—concerns that scientists argue are greatly overstated.
This emphasis on individual choice has overshadowed discussions about the communal advantages of vaccines.
According to Bruce Gellin, who led the National Vaccine Program Office within the Department of Health and Human Services during the George W. Bush and Barack Obama administrations, some vaccines are “unique because they both protect the person who receives the vaccine and protect the community in which people receive vaccines.”
Not every vaccine provides community protection. For instance, the rabies and tetanus vaccines protect only those vaccinated. However, several vaccines extend benefits beyond the individual to the community, safeguarding more than just the person receiving the immunization.
Below are some of the benefits of vaccines that we might be taking for granted and could lose if vaccination rates drop significantly.
Rubella: Vaccinating kids protects future kids
Rubella, once called German measles, was a common childhood illness before a vaccine became available in 1969. Most children recovered without long-term issues.
The real danger of rubella occurs during pregnancy, particularly in the first trimester. Such infections can result in miscarriage, stillbirth, or babies born with disabilities like deafness, blindness, or developmental delays. The last significant U.S. rubella outbreak in 1964-1965 resulted in approximately 20,000 children born with congenital rubella syndrome.
Since the vaccine’s introduction, these cases have become rare. From 2005 to 2018, only 15 children in the U.S. were born with congenital rubella.
“We’ve pretty much eliminated congenital rubella—a horrible, horrible disease with a lifetime of disability,” said Arthur Reingold, a professor of infectious disease epidemiology at the University of California at Berkeley.
Despite its absence in the U.S., rubella still circulates globally, posing a risk of imported cases.
Earlier this month, the Centers for Disease Control and Prevention (CDC) reported that a woman from Florida contracted rubella while visiting South Africa, a country that did not vaccinate against rubella when she was a child. Her baby was born with microcephaly, low birth weight, cataracts, and a congenital heart defect.
The MMR vaccine, which includes both measles and rubella protection, is essential as the rise in measles cases suggests a growing number of people are also susceptible to rubella. Measles, being more contagious, leads to quicker loss of herd immunity as vaccination rates drop. If this trend continues, rubella could reemerge.
“Measles was always going to be the first to come back,” said Andrew Pavia, a professor of pediatric infectious diseases at the University of Utah. “For others, we’re not that far out.”
Pneumococcal disease: Protecting babies drove down illness rates in seniors
In the early 2000s, a new vaccine called Prevnar was introduced in the U.S. to protect young children from pneumococcal disease. This vaccine targeted seven serotypes of pneumococcal bacteria, which cause mild infections like ear infections and sinusitis but can also lead to severe illnesses like pneumonia, bloodstream infections, and meningitis. The vaccine’s introduction resulted in a nearly 80% reduction in invasive pneumococcal disease cases in children.
Soon after, it was evident that the vaccine also benefited adults. Pneumococcal disease rates declined across all age groups, notably among older adults, who are at higher risk for these infections.
“Nobody vaccinated those grandparents,” said Jake Scott, a clinical associate professor of infectious diseases at Stanford University. “The children around them stopped carrying it.”
Pneumococci can spread from individuals with active infections and from healthy carriers who harbor the bacteria in their upper airways.
“If there are fewer bacteria in people’s throats, there are fewer bacteria circulating in the air when people breathe,” explained Gellin.
The introduction of a new version of Prevnar in 2010, which targeted 13 serotypes, led to a further decline in infections among older adults.
Eventually, the Food and Drug Administration extended the vaccine’s license, and the CDC recommended its use for older adults.
Chickenpox: Helping kids sidestep a nasty illness helps them avoid a worse one later
Those who grew up before the widespread use of the chickenpox vaccine likely experienced chickenpox and bear scars from the encounter. The varicella virus causes an itchy rash, and scratching can leave pockmark scars.
While chickenpox rarely leads to severe disease, the varicella zoster virus can remain dormant and reactivate later in life as shingles, a painful rash-like illness. Shingles typically affects older adults, particularly those with health conditions or on immune-suppressing medications.
Children who contract chickenpox are at risk for shingles later, prompting the development of shingles vaccines. Vaccinated children can also develop shingles, but cases are rare and usually milder than in those who had chickenpox.
By vaccinating their children against chickenpox, parents increase the odds that their kids will avoid the debilitating pain of shingles as adults.
… And sidestepping shingles may protect an adult’s future self from dementia
There is growing evidence that older adults vaccinated against shingles may have a reduced risk of developing dementia. “That is a real signal that doesn’t seem to be wanting to go away,” said Jeanne Marrazzo, CEO of the Infectious Diseases Society of America. “That to me at a population level is really quite profound.”
HPV: Vaccinating girls protects unvaccinated boys from some forms of cancer
The HPV vaccine is a medical breakthrough, preventing cancers in both women and men. Human papillomaviruses, transmitted through sexual contact, can cause various cancers, including cervical, anal, penile, and oropharyngeal cancers.
Initially licensed for girls, the HPV vaccine soon demonstrated benefits for boys as well.
“I think HPV is one of the most elegant herd immunity stories that we have, because the indirect protection showed up so clearly and so quickly, in a population that wasn’t even targeted by the original program,” Scott said.
Within five years of Australia’s rollout—targeting girls only—researchers observed significant declines in genital warts among heterosexual men. A U.S. study found that oral infections with HPV strains covered by the vaccine dropped 38% between 2009-2010 and 2015-2016 in unvaccinated men, while rates of HPV oral infections with non-vaccine strains remained stable.
Many countries now vaccinate both girls and boys against HPV.
Measles: Driving down spread shields highly vulnerable people
Camille Kotton is alarmed by the increasing number of measles outbreaks in the U.S. Kotton, a Massachusetts General Hospital physician who focuses on minimizing infectious disease risks for immunocompromised patients, recognizes the heightened risk for these individuals as measles cases rise.
Measles is a severe infection in children, leading to hospitalizations and potentially death. The CDC estimates that before the widespread use of the measles vaccine, the U.S. saw 3 to 4 million infections annually, with 400-500 deaths. Last year, two children and an adult—none vaccinated—died from measles in the U.S.
Measles poses an even greater threat to those with compromised immune systems, such as organ transplant recipients who take immunosuppressive medications.
“In older immunocompromised adults, it could be a very wild, volatile, high-risk situation,” Kotton said.
Historically, high measles vaccination rates have protected immunocompromised individuals. During the early 2000s, confirmed cases were typically in the dozens each year. This is no longer the case, with 1,362 confirmed cases reported in the first 10 weeks of this year alone—more than in the first 14 years of this century combined.
Kotton advises that her patients, if exposed to measles and not immune, should receive measles immunoglobulin, a costly serum that takes six to eight hours to administer. However, she notes that the country lacks the resources and infrastructure to provide this protection on a large scale if measles transmission continues to rise.
“We’re going to be able to maybe give post-exposure prophylaxis to some bunch of people, but it would not be on the scale that might be needed,” Kotton said.
Meningococcal B: Protecting against a deadly disease may also fend off an STI
About a decade ago, researchers observed an unexpected trend in gonorrhea control efforts. Studies showed that teens and young adults vaccinated against meningococcal B had lower rates of gonorrhea, a sexually transmitted infection, compared to their unvaccinated peers.
Meningococcal B bacteria can cause rare but deadly outbreaks, particularly among teens and young adults. Infection can swiftly progress from health to death, with survivors facing potential limb loss or brain damage.
The bacteria responsible for meningococcal B, Neisseria meningitidis, is related to Neisseria gonorrhoeae, which causes gonorrhea. Several studies over the past decade suggest that the vaccine for the former offers some protection against the latter, with protection rates around 30% to 40%.
The U.K.’s Joint Committee on Vaccination and Immunisation has recommended offering the meningococcal B vaccine to those at high risk for gonorrhea based on existing evidence.
However, enthusiasm for this approach was dampened when a recent randomized controlled trial in Australia failed to demonstrate a benefit in a study involving 587 men who have sex with men. Despite this, Marrazzo remains hopeful, suggesting that upcoming studies in more diverse populations might yield different outcomes.
“There are a couple of big randomized control trials coming out this year that hopefully will give us more definitive answers in additional populations,” she said.
Multiple vaccines: Averting illnesses in kids protects productivity
The principal aim of public health vaccination efforts is to prevent illness, both at the individual and community level. Additionally, vaccines offer the benefit of reducing parental work absences when children fall ill.
Vaccines for various diseases have significantly decreased the number of pediatric hospitalizations annually. Vaccines against Haemophilus influenzae type B (Hib), rotavirus, and chickenpox, among others, have alleviated pressure on pediatric hospitals and families nationwide, according to Pavia.
“Back when the chickenpox vaccine was made routine for kids, one of the major arguments was, it’s true that chickenpox rarely killed the child or resulted in hospitalization, but parents lost an immense amount of productive work time,” Reingold said. “That was a substantial component of the economic analysis for why we should routinely give the chickenpox vaccine, was preventing the lost work time of the parent.”
Advocates of vaccines appreciate the widespread benefits these tools have created, effects not always foreseen during their development. However, parents skeptical of vaccines may not be swayed by arguments focused on societal benefits. Their primary concern is their child’s well-being or their own.
Reingold redirects the argument to the individual child, specifically regarding measles.
“If we have enough cases, kids will die,” he said. “And I don’t want any kids to die if we have a safe and effective way to prevent it.”
