Latest news with #vaccinehesitancy
Fast Company
09-06-2025
- Health
- Fast Company
How game theory explains vaccination rates and parents' choices
When outbreaks of vaccine-preventable diseases such as measles occur despite highly effective vaccines being available, it's easy to conclude that parents who don't vaccinate their children are misguided, selfish, or have fallen prey to misinformation. As professors with expertise in vaccine policy and health economics, we argue that the decision not to vaccinate isn't simply about misinformation or hesitancy. In our view, it involves game theory, a mathematical framework that helps explain how reasonable people can make choices that collectively lead to outcomes that endanger them. Game theory reveals that vaccine hesitancy is not a moral failure, but simply the predictable outcome of a system in which individual and collective incentives aren't properly aligned. Game theory meets vaccines Game theory examines how people make decisions when their outcomes depend on what others choose. In his research on the topic, Nobel Prize-winning mathematician John Nash, portrayed in the movie A Beautiful Mind, showed that in many situations, individually rational choices don't automatically create the best outcome for everyone. Vaccination decisions perfectly illustrate this principle. When a parent decides whether to vaccinate their child against measles, for instance, they weigh the small risk of vaccine side effects against the risks posed by the disease. But here's the crucial insight: The risk of disease depends on what other parents decide. If nearly everyone vaccinates, herd immunity —essentially, vaccinating enough people—will stop the disease's spread. But once herd immunity is achieved, individual parents may decide that not vaccinating is the less risky option for their kid. In other words, because of a fundamental tension between individual choice and collective welfare, relying solely on individual choice may not achieve public health goals. This makes vaccine decisions fundamentally different from most other health decisions. When you decide whether to take medication for high blood pressure, your outcome depends only on your choice. But with vaccines, everyone is connected. This interconnectedness has played out dramatically in Texas, where the largest U.S. measles outbreak in a decade originated. As vaccination rates dropped in certain communities, the disease—once declared eliminated in the U.S.—returned. One county's vaccination rate fell from 96% to 81% over just five years. Considering that about 95% of people in a community must be vaccinated to achieve herd immunity, the decline created perfect conditions for the current outbreak. This isn't coincidence; it's game theory playing out in real time. When vaccination rates are high, not vaccinating seems rational for each individual family, but when enough families make this choice, collective protection collapses. The free-rider problem This dynamic creates what economists call a free-rider problem. When vaccination rates are high, an individual might benefit from herd immunity without accepting even the minimal vaccine risks. Game theory predicts something surprising: Even with a hypothetically perfect vaccine—faultless efficacy, zero side effects—voluntary vaccination programs will never achieve 100% coverage. Once coverage is high enough, some rational individuals will always choose to be free riders, benefiting from the herd immunity provided by others. And when rates drop, as they have, dramatically, over the past five years, disease models predict exactly what we're seeing: the return of outbreaks. Game theory reveals another pattern: For highly contagious diseases, vaccination rates tend to decline rapidly following safety concerns, while recovery occurs much more slowly. This, too, is a mathematical property of the system because decline and recovery have different incentive structures. When safety concerns arise, many parents get worried at the same time and stop vaccinating, causing vaccination rates to drop quickly. But recovery is slower because it requires both rebuilding trust and overcoming the free-rider problem—each parent waits for others to vaccinate first. Small changes in perception can cause large shifts in behavior. Media coverage, social networks, and health messaging all influence these perceptions, potentially moving communities toward or away from these critical thresholds. Mathematics also predicts how people's decisions about vaccination can cluster. As parents observe others' choices, local norms develop, so the more parents skip the vaccine in a community, the more others are likely to follow suit. Game theorists refer to the resulting pockets of low vaccine uptake as susceptibility clusters. These clusters allow diseases to persist even when overall vaccination rates appear adequate. A 95% statewide or national average could mean uniform vaccine coverage, which would prevent outbreaks. Alternatively, it could mean some areas with near-100% coverage and others with dangerously low rates that enable local outbreaks. Not a moral failure All this means that the dramatic fall in vaccination rates was predicted by game theory, and therefore more a reflection of system vulnerability than of a moral failure of individuals. What's more, blaming parents for making selfish choices can also backfire by making them more defensive and less likely to reconsider their views. Much more helpful would be approaches that acknowledge the tensions between individual and collective interests and that work with, rather than against, the mental calculations informing how people make decisions in interconnected systems. Research shows that communities experiencing outbreaks respond differently to messaging that frames vaccination as a community problem versus messaging that implies moral failure. In a 2021 study of a community with falling vaccination rates, approaches that acknowledged parents' genuine concerns while emphasizing the need for community protection made parents 24% more likely to consider vaccinating, while approaches that emphasized personal responsibility or implied selfishness actually decreased their willingness to consider it. This confirms what game theory predicts: When people feel their decision-making is under moral attack, they often become more entrenched in their positions rather than more open to change. Better communication strategies Understanding how people weigh vaccine risks and benefits points to better approaches to communication. For example, clearly conveying risks can help: The 1-in-500 death rate from measles far outweighs the extraordinarily rare serious vaccine side effects. That may sound obvious, but it's often missing from public discussion. Also, different communities need different approaches: High-vaccination areas need help staying on track, while low-vaccination areas need trust rebuilt. Consistency matters tremendously. Research shows that when health experts give conflicting information or change their message, people become more suspicious and decide to hold off on vaccines. And dramatic scare tactics about disease can backfire by pushing people toward extreme positions. Making vaccination decisions visible within communities—through community discussions and school-level reporting, where possible—can help establish positive social norms. When parents understand that vaccination protects vulnerable community members, like infants too young for vaccines or people with medical conditions, it helps bridge the gap between individual and collective interests.
The Independent
05-06-2025
- Entertainment
- The Independent
‘She's sold out': Meghan McCain accused of going ‘full grift' after promoting COVID vaccine ‘detox'
Meghan McCain, who once chastised rap superstar Nikki Minaj for spreading 'vaccine hesitancy' during the COVID-19 pandemic, is now partnering with a fringe 'wellness' company to promote a 'detox' supplement for those who 'regret taking the shot.' The former host of The View hawking $90 bottles of the 'Ultimate Spike Detox' prompted critics to call out the daughter of John McCain for going 'full grift' and accuse her of selling out 'to the crazies' after championing herself as a 'voice of reason on the right' for years. McCain, who now hosts a twice-weekly podcast, took to X on Wednesday to announce that she was 'thrilled to partner' with The Wellness Company, a business run by Canadian entrepreneur Foster Coulson that is 'rooted in conspiracy theories' and employs 'several doctors who have been accused of spreading medical misinformation.' Coulson, who has paid accused rapist and mysogynistic influencer Andrew Tate to sell his products, says he is creating a 'parallel economy' for 'consumers who believe their freedom is under threat by censorious elites and corrupt scientists.' Other ventures he has backed include a dating site for unvaccinated singles and an 'anti-woke' coffee brand. One of the doctors Coulson has employed is Dr. Peter McCullough, who is listed as The Wellness Company's 'chief scientific officer' and developed the 'Ultimate Spike Detox' supplement line. McCullough, who was an early proponent of the debunked hydroxychloroquine COVID-19 treatment, co-authored a retracted paper that claimed 74 percent of autopsies of people who 'suddenly died' showed they were vaccinated, suggesting that was the cause. According to the company's site, the 'extra-strength formula' designed by the 'world's leading pandemic expert' includes 'a key enzyme that may help break down spike protein and disrupt its function.' It also claims it will provide the user's 'body with unparalleled support for cellular defense and detoxification.' Despite McCullough having his board certifications for cardiovascular disease and internal medicine revoked by the American Board of Internal Medicine earlier this year for promoting misinformation about COVID-19 vaccinations, McCain urged her followers to buy the supplements – and even gave her name as a promotional discount code. 'Concerning data continues to emerge regarding mRNA vaccines and their unforeseen health impacts,' she tweeted on Wednesday. 'They did not deliver what was promised by government + health officials. I have friends who suffered – heart and menstruation issues & more. It's time to pull them off the market NOW.' McCain added: 'Thrilled to partner with The Wellness Company! If you regret taking the shot, there's hope. Dr. Peter McCullough's all-natural Ultimate Spike Detox is helping people worldwide. Use code MCCAIN for 10% off + FREE shipping on all orders.' It was just a few short years ago, however, that McCain was criticizing others as being 'deeply irresponsible' for pushing skepticism over the vaccines. Additionally, when the Biden administration was first rolling out vaccinations to the public, she expressed 'vaccine envy' because she wasn't sure when she was personally going to get the shot. Along those lines, she complained during a July 2021 broadcast of The View that the Biden White House turned down her offer to help the president reach out to 'vaccine-hesitant' Republicans and convince them to get the jab. McCain promoting a disgraced doctor's supplements while partnering with a company that is pandering to anti-vax conspiracists prompted several media figures and observers to call her out as a right-wing grifter. 'Meghan Goes Full Grift: Is Meghan McCain that desperate for some extra cash?' Status News founder Oliver Darcy pointed out in his newsletter, adding: 'For someone who spent years portraying herself as the voice of reason on the right, this is quite the grift.' Gizmodo reporter Matt Novak shared a screenshot of McCain's tweet and noted that 'the entire conservative movement must be funded by health grifts at this point,' while author Stephen Elliott claimed that 'they all sell snake oil eventually' because the 'incentives are too great not to.' Cybersecurity expert Rob Graham, meanwhile, said that while McCain 'would speak out against the crazies' and defend actual science five years ago, she has since 'been captured by her audience' now that she is a conservative podcaster. 'Her audience is drifting further to the fringe, so is she,' he stated. 'So she's now become the thing she [fought] against 5 years ago. From being the champion on the Right-wing against the crazies, she's sold out to the crazies.' Ironically, it was just a few months ago that McCain herself appeared to take issue with those she saw as hustling and camming their audience. 'Grifters can only keep up a grift for so long,' she tweeted in December. Representatives for McCain did not respond to a request for comment. This isn't the first time McCain has been accused of hypocrisy. Earlier this year, she announced that she was 'excited' to be joining a media startup run by political journalist Mark Halperin, whom McCain had publicly trashed years prior over allegations that he sexually assaulted and harassed multiple women. 'With age comes wisdom and different perspectives on people. I am now a 40 year old mother of two. I have grown and evolved like everyone else, particularly in the past five years — Mark has also grown and evolved,' she said when asked at the time by The Independent what had changed regarding her views on Halperin. 'Like Mark, at this point in my life I believe in giving people the presumption of grace and forgiveness as I would like it in return.' Just three months after joining Halperin's 2way network, low viewership continued to plague the show, prompting her to merge her existing Citizen McCain podcast with the YouTube program in hopes of sparking interest.
Daily Mail
02-06-2025
- General
- Daily Mail
Frightening map reveals US counties where world's most infectious disease is set to surge
Experts are warning of a national decline in the measles-mumps-rubella (MMR) vaccination rate among US children as cases continue to spike in the country. A new study found uptake of the vaccine among children declined in eight in 10 US counties last year. Overall, vaccine rates fell three percent across the country. It means that merely 91 percent of children are vaccinated against measles, which is well below the 95 percent need to prevent the disease from spreading and causing death. The Johns Hopkins University researchers warned that if vaccination rates continue to fall, measles is likely to completely return and become a common infection among Americans. As of last week, more than 1,000 confirmed cases and at least three deaths in the US have been reported - the first measles-caused deaths in a decade. A majority of those infected as well as the all of the deceased had not received their MMR vaccine - primarily due to vaccine hesitancy and misinformation, experts say. Without the MMR vaccine, which is 97 percent effective at stopping infections, measles is thought to be the most infectious disease in the world. It causes tiny white spots inside the mouth, flat red spots on the neck, torso, arms, legs, and feet, ear infections and an intense fever. In terms of when to get vaccinated, experts say children need two doses of MMR vaccine: the first dose at age 12-15 months, and the second dose at age 4-6 years. Babies ages 6-11 months should get an early dose if traveling internationally. Adults should also check to see if they are immune to measles. In the study, the researchers collected two-dose MMR vaccination data on kindergarteners (children aged five years old) for each school year starting 2017-2018 to 2023-2024 in 2,066 counties across 38 states. The scientists analyzed the collected data through multiple statistical models to find out how many children were vaccinated. Out of the studied counties, 78 percent or 1,614 counties reported drops in MMR vaccination rates. The average county-level vaccination rate was also seen to fall from 93.92 percent pre-Covid pandemic to 91.26 percent post-pandemic. Only four of the 33 states studied, only California, Connecticut, Maine and New York reported an increase in the vaccine uptake. Lauren Gardner, senior author and director of Johns Hopkins University's Center for Systems Science and Engineering said of the results: 'This open, high resolution dataset provides a critical resource to explore and better understand the country's vaccination landscape and its implications for the risk of measles spread.' They also noted that with the exception of 2019, this year is the highest number of cases reported in the US in a single year in over three decades - with the vast majority of cases occurring in unvaccinated children. The study was published today in the JAMA Network Journal. If one person has measles, up to 90 percent of the people close to that person who are not immune will also become infected. The average measles patient would infect up to 18 others if they were also not vaccinated. People who had the original Covid strain, by comparison, infected on average just two people, though this number rose considerably with new variants. If unvaccinated, about one in five people who are infected are hospitalized while one in 20 children develop pneumonia. The last time measles was this rife in the US was in 2019, when there were 1,274 cases reported for the entire year. Prior to that, the biggest outbreak was in 1990, with numbers spiking to more than 27,000. Currently, the affected states are: Arizona, California, District of Columbia, Florida, Georgia, Idaho, Illinois, Indiana, Louisiana, Maryland, Massachusetts, Michigan, Minnesota, Missouri, New Hampshire, New Jersey, New Mexico, New York City, New York State, North Carolina, Ohio, Oklahoma, Oregon, Pennsylvania, South Carolina, South Dakota, Tennessee, Texas, Vermont, Virginia, Washington, Wisconsin, and West Virginia. IS THIS DEFO UP TO DATE? Of these cases, three-quarters are in children under the age of 19. Measles was officially eradicated in the US in 2000 amid a successful vaccination campaign. At the time, the CDC described achieving measles elimination status in the US as a 'historic public health achievement'.
ABC News
16-05-2025
- Health
- ABC News
Why childhood vaccination is dropping and what we can do about it
An alarming decline in childhood vaccination rates is a "wake-up call" for all levels of Australian government and the health sector, according to the peak body for doctors. President of the Australian Medical Association (AMA), Dr Danielle McMullen, said new figures released this week show we urgently "need to do more" to address the issue. "Perhaps as a country we've become complacent in trusting our really excellent vaccination rates," Dr McMullen said. Tasmanian GP Tim Jones said he was talking to hesitant patients about vaccination every day. "I'm having four to five conversations a day with families about vaccinations particularly as it applies to their children." He said some were skeptical about both the safety of vaccinations and whether the diseases they protect against are, in fact, dangerous, while others felt apathetic and burnt out in the wake of the pandemic. "They're fearful, they're worried about harm, they don't want to hurt the people they love." Dr Jones has been a GP for almost ten years and said vaccine hesitancy was much higher now than it was when he first started working as a doctor. Dr Jones is also the chair of child and young person's health at the Royal Australian College of General Practitioners. He said it's really important to listen to people's fear and hesitancy about vaccines, so they feel safe. "As a GP working in 2025, I did not think I would be seeing kids in the developed world die of measles and yet this is the situation we're now facing" Dr Jones said fear and hesitancy were the main issues he's seeing in Hobart, but there are also significant economic and cultural barriers with some people struggling to access affordable, convenient care. New data from the National Centre for Immunisation Research and Surveillance (NCIRS) shows a widespread decline in childhood vaccinations for a range of diseases over the past five years. The proportion of children who are up-to-date with their immunisations by the age of 12 months fell from 94.8 per cent in 2020 to 91.6 per cent last year. The percentage of those fully vaccinated by age two was down from 92.1 per cent to 89.4 per cent in the same time frame. For highly contagious diseases like measles, approximately 95 per cent vaccination coverage is needed to maintain herd immunity. Source: Department of Health Dr McMullen from the AMA said a review of Australia's public health vaccination campaigns was needed to "refocus" the messaging and target misinformation. "Most people are getting the message that vaccinations are a really critical part of our health system. "Just blasting them with more and more information may not change the dial. "What we've really got to do is be targeted and work out for people who aren't being vaccinated, what are the barriers they're facing and how do we address those?" There are practical and ideological reasons why some parents aren't vaccinating their children, either fully or partially. In practical terms, cost and access to care can be barriers. Although childhood immunisations are free, sometimes GPs will charge for the appointment, especially in regional or remote areas. And even if the appointment is free, there may be the cost of taking time off work or transport to the doctor. Even getting an appointment can be a battle too. "Childhood vaccinations are due every few weeks so sometimes a GP is really busy and you can't get an appointment every six weeks when it's due," said Jessica Kaufman, a lead researcher on the Vaccine Uptake Group at the Murdoch Children's Research Institute. "Then before you know it you've fallen behind." The other reasons for reluctance are linked to emotions and social influence. Dr Kaufman is part of the National Vaccination Insights Project which surveyed 2,000 parents about childhood vaccination last year. About 50 per cent of parents with unvaccinated children said they didn't believe vaccines were safe and around 40 per cent didn't think vaccines were effective at preventing disease. But the most common barrier for all surveyed parents (including those who did vaccinate their children) was "feeling distressed when thinking about vaccinating their child". "A lot of parents worry about seeing their kids in pain, or worry they are making the right decision or may just have a needle phobia themselves," Dr Kaufman said. This data was collected last April so Dr Kaufman said it does not reflect the rise in vaccine misinformation that we've seen since the Trump administration was re-elected in the US. US Secretary of Health Robert F. Kennedy is a well-known vaccine skeptic who has revived the debunked claim that vaccines cause autism and promoted treatments for measles that have no grounding in scientific evidence, such as vitamin A. "What's happening in the US means things that used to be fringe beliefs are becoming mainstream and anecdotally I'm hearing from nurses that people are coming into clinic with questions about things like vitamin A supplementation," Dr Kaufman said. Dr Kaufman said employing more practice nurses who can give vaccines at GP clinics, establishing walk-in vaccine clinics and allowing pharmacists to give childhood immunisations could all help reverse the trend. Creating a positive and supportive environment at the clinics where the vaccinations are administered is also crucial to ease distress. "Distraction techniques can help or allowing the mother to breastfeed while the baby gets vaccinated," Dr Kaufman said. "Another idea would be to have a Medicare item that incentivises vaccination conversations so there's time to have good conversations that can be bulk billed." Julie Leask is a social scientist who is involved in the National Vaccination Insights Project, specifically looking at influenza vaccination uptake. She said the simple act of sending reminders needed to be revitalised. "Reminders work but they are quite ad hoc right now and it's up to the GP practice. I'm not aware of any jurisdictions using reminders systematically." Getting through to parents who don't believe vaccines are safe or effective is a lot more challenging but fear campaigns are not effective, Dr Kaufman said. "Research has shown this can overwhelm people as they might already be scared of the vaccine and potential side effects and then they are shown scary images of people with the disease … this can put them into a kind of analysis paralysis so they do nothing." She said the most effective way to get through to people with doubts is through community outreach, which was used a lot at the height of the COVID-19 pandemic. This involves people who are already trusted by a community getting trained in how to have conversations about vaccination within their cultural, religious, political or social network. "This is a lot more useful than something like the 'arm yourself' campaign we saw during COVID." Health Minister Mark Butler said the decline in childhood vaccination was "alarming" and the government was currently finalising its National Immunisation Strategy for 2025 to 2030 which will outline how to improve uptake.
Yahoo
11-05-2025
- Health
- Yahoo
RFK Jr. Spews Wild Anti-Vax Theories As Measles Cases Surge
As measles cases surge past quadruple digits for the first time in three decades, Health and Human Services Secretary Robert F. Kennedy Jr. has been defending religious vaccine refusal and spreading pseudoscience on Fox News. 'The MMR vaccine that we currently use has millions of particles that were created from aborted fetal tissue, millions of DNA fragments,' RFK Jr. told Fox News host Bret Baier in a report aired on Thursday. It's a wildly misleading statement. The rubella component of the MMR vaccine is grown in a lab-cultured cell line originally derived from fetal tissue in the 1960s, but no actual tissue cells are present in the vaccine. Trace DNA fragments are non-functional and regulated to be safe. As of May 8, the CDC confirmed a total of 1,001 measles cases have already been detected in 2025, a sharp increase from the 285 reported in all of 2024. So far, three people have died from the disease. Framing the debate as one of personal freedom and religious persecution, Kennedy said that people refusing the vaccine on moral grounds were being 'treated like lepers' and deserved more 'compassion' in hospital settings. 'Even in 1963, before the introduction of the vaccine, there were 400 deaths a year and there were up to 2 million measles cases,' Kennedy said. 'Only very, very sick kids should die from measles.' Baier clarified that the MMR vaccine doesn't contain fetal cells, to which Kennedy asserted that the presence of DNA fragments justifies the religious objection. 'I might not share those objections, [but] I respect them,' he said. Kennedy admitted that the measles outbreak in Texas, which has now spread to 30 other states, has largely been among the Mennonite community, and that the virus will spread through an unvaccinated population. Measles is one of the most contagious viruses on Earth, with a 90 percent infection rate among unvaccinated people. Herd immunity for the disease requires roughly 95 percent vaccination coverage, something America slipped below in 2021. This makes outbreaks more likely and potentially uncontrollable if they begin to circulate in wider, unvaccinated populations. RFK Jr. has previously come under fire for suggesting it would be better if 'everybody got measles,' arguing that infection provides lifetime coverage in a way the vaccine does not. However, an MMR vaccine, which is 97 percent effective for life, does not come with possible side effects of pneumonia, encephalitis, or death, unlike a measles infection.
