Even a small uptick in vaccination could prevent millions of US measles cases. Here’s how
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(NEW YORK) — Measles cases are continuing to spread throughout the U.S. with outbreaks in at least six states.
Public health experts have previously said lagging vaccination rates are to blame for the rise in cases, at least partly due to vaccine hesitancy and vaccine fatigue left over from the COVID-19 pandemic.
However, even a small uptick in MMR (measles, mumps and rubella) vaccination could prevent millions of infections, according to new research.
The study, published in JAMA last week, used a model to simulate the spread of vaccine-preventable infectious diseases across the U.S., evaluating different scenarios with different vaccination rates over a 25-year period.
The Centers for Disease Control and Prevention (CDC) currently recommends that people receive two vaccine doses — the first at 12 to 15 months and the second between 4 and 6 years old. One dose is 93% effective and two doses are 97% effective against measles, the CDC says. Most vaccinated adults don’t need an additional dose.
At current vaccination rates, the model predicts measles could once again become endemic — constantly present — in the U.S. with an estimated 851,300 cases over 25 years. If vaccination rates decline by just 10%, the model estimates 11.1 million cases of measles over 25 years.
CDC data show vaccination rates have been lagging in recent years. During the 2023 to 2024 school year, 92.7% of kindergartners received the MMR vaccine, according to data. This is lower than the 93.1% seen the previous school year and the 95.2% seen in the 2019 to 2020 school year, prior to the COVID-19 pandemic.
“That result — that we’re already at this tipping point for measles in the U.S. — was a really striking finding that somewhat surprised us as well,” Dr. Nathan Lo, study co-author and an infectious diseases physician at Stanford Medicine, told ABC News.
“We continue to see measles outbreaks, but, by doing the study … you start to crystallize that result that even under the current levels of vaccine decline, there is a very feasible scenario where, over time, our country has measles return where it’s a common household disease again.”
Dr. William Schaffner, a professor of preventive medicine at Vanderbilt University Medical Center in Nashville, who was not involved in the study, said the findings are a “well-thought-out worst-case scenario.”
“I’m not entirely sure that would actually happen because … the general level of vaccination remains pretty high, but there are pockets of unvaccinated children, and what you’re seeing now is the fact that this virus has been reintroduced several times from other parts of the world,” he told ABC News. “I think it’s a bit of a worst-case scenario but, as a worst-case scenario, it’s scary and, in that sense, reasonable.”
However, the model estimated that just a 5% increase in vaccination would lead to only 5,800 cases over the same 25-year period.
This is because when more than 95% of people in a community are vaccinated, most are protected from measles through community immunity, also known as herd immunity, according to the CDC.
“My hope is that this study can provide that data to parents to say, ‘This is the benefit of continuing to vaccinate your child. This is the kind of alternate reality that we’re preventing. And yes, the risks aren’t here right now, but perhaps not too far off,'” Lo said.
Schaffner said there are pockets of the U.S. where MMR vaccination rates are 80% or less and vaccination rates would need to increase substantially in those areas to reduce the number of cases long-term.
However, “if we increase the level of vaccination by a small amount that would reduce the risk of other small outbreaks here and there,” Schaffner said.
The study also found that a 50% drop in vaccinations would lead to an estimated 51.2 million cases over 25 years, but Lo thinks that would only occur if there were a large-scale policy change by the Department of Health and Human Services or the CDC to reduce or remove the childhood vaccine recommendation.
As of Friday, the CDC has confirmed nearly 900 measles cases in at least 29 states. That number is likely an undercount due to delays in states reporting cases to the federal health agency.
In western Texas, an outbreak has been spreading with 663 reported cases of measles, according to new data published Tuesday by the state Department of State Health Services. At least 87 people have been hospitalized over the course of the outbreak.
Measles was declared eliminated from the U.S. in 2000 due to the highly effective vaccination program, according to the CDC. However, an outbreak lasting 12 months or more would threaten to end measles elimination status in the U.S. The Texas outbreak began in January of this year.
To drive vaccination rates up, Lo and Schaffner recommend that parents who haven’t vaccinated their children yet speak to their pediatrician to address their concerns.
“We have to provide recommendations and let people know the facts that these vaccines are very effective and that they are safe,” Schaffner said. “But we have to do more to try to reach out and provide reassurance, and this has to be done very much on a local basis.”
For example, when it comes to the community affected in Texas, Schaffner said they need local influencers they trust to turn to.
“Speak with your local physician, health care provider, the person who cares for your children,” Schaffner said. “Have a conversation with them, and that’s our best hope for regaining some of this trust which public health had and which has slipped away.”
(WASHINGTON) — Measles is continuing to spread across the United States, as outbreaks grow in western Texas and New Mexico.
Between the two states, 256 cases have been confirmed as of Thursday, mostly in those who are unvaccinated or with unknown vaccination status, according to state health officials. At least one unvaccinated school-aged child in Texas has died and another suspected death is being investigated in New Mexico in an unvaccinated adult. At least 10 other states have also confirmed cases, according to the Centers for Disease Control and Prevention.
As health care professionals work to care for patients, they are also attempting to combat the proliferation of misinformation about how to prevent and treat the disease, some tell ABC News.
Health and Human Services Secretary Robert F. Kennedy Jr. has been one of the prominent voices on measles, making comments that public health experts say are not accurate.
In multiple interviews, Kennedy has claimed that vitamin A and cod liver oil are effective treatments for measles. He also said that poor diet contributes to severe cases of measles and that — while vaccines prevent illness — they also cause severe illnesses and even death.
Some public health experts told ABC News these statements are not rooted in scientific evidence and could be quite dangerous for the public.
“I think it’s really important to try to stay away from these ideas of fringe theories or ideas that have not been scientifically proven,” Kirsten Hokeness, director of the school of health and behavioral sciences at Bryant University, in Rhode Island, told ABC News.
Vitamin A as a form of treatment
During an interview on Fox News with Sean Hannity on Tuesday, Kennedy said that HHS was currently providing vitamin A to measles patients for treatment. He claimed vitamin A can “dramatically” reduce measles deaths.
The World Health Organization recommends two doses of vitamin A in children and adults with measles to restore low vitamin A levels, which can help prevent eye damage and blindness.
However, experts who spoke with ABC News said it is not an antiviral treatment against measles (meaning it does not prevent infections), nor is there one available.
“Because it has been described that patients with vitamin A deficiency can have a more severe course, the WHO recommends low doses of vitamin A for children diagnosed with measles,” Dr. Carla Garcia Carreno, a pediatric infectious disease specialist at Children’s Medical Center Plano in Texas, told ABC News. “This is a supplementation in case of deficiency, and it is not intended to treat the virus. High doses of vitamin A can have serious consequences.”
“Neither vitamin A nor cod liver oil will treat measles,” she concluded.
Poor diet linked to severe measles disease
Kennedy has claimed that poor nutrition plays a role in causing severe measles disease and that a healthy diet can lessen severity.
While malnutrition can be a factor in severe disease, malnutrition and nutritional deficits in measles patients have historically been seen in underdeveloped countries, according to experts.
Additionally, studies have found that mass nutritional supplementation “followed by an increase in vaccination coverage” can reduce measles infection and mortality.
“Certainly, good nutrition can promote a healthy immune system, and it’s a good idea for everyone to try to maintain good nutrition, but it’s certainly not a substitute for vaccination,” Dr. Scott Weaver, director of the Institute for Human Infections and Immunity at the University of Texas Medical Branch, told ABC News. “There’s no evidence that it can prevent infection, no evidence that it can prevent an infected person from spreading the virus and contributing to one of these outbreaks.”
“So, I want to be very clear, good nutrition is absolutely no substitute for vaccination to prevent someone’s own risk for developing severe, maybe fatal, measles,” he added.
Claims about the safety of the measles vaccine
The CDC currently recommends that people receive two doses of the measles, mumps, rubella vaccine, the first at ages 12 to 15 months and the second between 4 and 6 years old.
One dose is 93% effective, and two doses are 97% effective, the CDC says. Most vaccinated adults don’t need a booster.
Kennedy has said vaccines do “stop the spread of the disease” but also said they cause “adverse events.”
“It does cause deaths every year. It causes all the illnesses that measles itself [causes], encephalitis and blindness, et cetera,” he told Hannity, without providing evidence.
Weaver said there is no vaccine that is without risks but that the MMR vaccine is incredibly safe and effective.
“There’s no evidence that it has severe outcomes … similar to what the measles virus infection causes,” he told ABC News. “It certainly can cause very minor reactions at the site of injection, like just about every vaccine, but it’s one of the safest vaccines that’s ever been developed.”
Weaver added that the risks of complications from a measles infection far outweigh any risks from the MMR vaccine.
As for Kennedy’s unfounded claim that the MMR vaccine causes death, a 2015 CDC review published in the journal Vaccine found such claims are deaths reported to the U.S. Vaccine Adverse Event Reporting System – a voluntary reporting system “that accepts any submitted report of an adverse event without judging its clinical significance or whether it was caused by a vaccination.”
The review found that many of the deaths reported to VAERS claiming to be linked to the MMR included children who has serious underlying medical conditions or had deaths that were unrelated to the vaccine, including accidental deaths.
“These complete VAERS reports and any accompanying medical records, autopsy reports and death certificates have been reviewed in depth by FDA and CDC physicians and no concerning patterns have emerged that would suggest a causal relationship with the MMR vaccine and death,” the review stated.
Questioning ‘benefits’ of measles and fatality rate
Kennedy claimed in an interview with Fox News senior medical analyst Dr. Marc Seigel over the weekend that is “almost impossible” for measles to kill a healthy individual.
Some people who contract measles may suffer severe complications as a result of infection. While those most at risk include children younger than age 5, pregnant people and those with weakened immune systems, anybody can experience complications.
About in 1 in 5 unvaccinated people who contract measles are hospitalized and about 1 in 20 children with measles develop pneumonia, which is the most common cause of death in young children who get infected.
About one in 10 children infected with measles develop ear infections as well, which can lead to hearing loss, data shows.
Additionally, about 1 out of every 1,000 children with measles will develop encephalitis — which is the swelling of the brain and can lead to brain damage — and up to 3 out of every 1,000 children with measles will die from respiratory and neurologic complications, the CDC says.
Recently, Texas health officials reported the death of an unvaccinated school-aged child, the first death from measles recorded in the U.S. in a decade. The child was healthy and had no preexisting conditions, officials said.
“The CDC estimates that 1 in 5 people [who] get infected with measles ends up in the hospital,” Hokeness said. “So, this approach to relying on sort of this natural immunity doesn’t make sense when we have a vaccine which prevents it in the first place.”
“But, in short, there’s really no benefit to this idea of natural immunity and naturally acquiring the virus. That’s why we’ve developed the vaccines that work so well,” she added.
Kennedy also claimed in his interview that natural immunity from measles may protect against cancer and heart disease. There is no evidence to suggest either of those are true, experts said.
“If you want to take your chances with getting natural infection, hoping that there might be some very small benefit to that, it’s a very big risk to take, because you may very well get severe measles infection,” Weaver said.
Overall, experts advised relying on scientifically proven medical information.
“We should leverage the knowledge that we’ve gained over the years and not spend our time focusing on alternative possibilities,” she said.
(WASHINGTON) — The first 100 days of President Donald Trump’s second term have been filled with mass firings, cancellations of research grants, university funding cuts and questions over what should be studied.
Thousands of people have been let go at federal agencies and critical research has been put on hold. Additionally, Health and Human Services Secretary Robert F. Kennedy Jr. has questioned the safety and efficacy of vaccines and antidepressant medications despite dozens of studies proving they are safe and effective.
Doctors and public health specialists critical of the administration tell ABC News they view these actions as an “attack” on science, damaging the reputation of respected agencies and by questioning what is believed to be established science.
“It’s completely unprecedented,” Steve Cohen, senior vice dean of Columbia University’s School of Professional Studies and a professor of public affairs at Columbia’s School of International and Public Affairs, told ABC News. “It’s frankly a little unhinged. I’ve never seen anything like it.”
The White House did not respond to ABC News’ request for comment.
An HHS official told ABC News that framing the actions of the admiration as an “attack” is “fundamentally dishonest.”
“Further reviewing pharmaceutical products with gold standard science and common sense is not an'”attack on science’ — it’s what the American people have asked for and deserve,” the official said. ” Let’s be clear: Secretary Kennedy is not anti-vaccine — he is pro-safety, pro-transparency, and pro-accountability.”
Thousands of layoffs
Earlier this month, HHS began to lay off 10,000 workers as part of a massive restructuring plan.
Sources previously told ABC News that affected offices included most of the Centers for Disease Control and Prevention’s Office on Smoking and Health, key offices in the Center for Tobacco Products, most of the National Institute for Occupational Safety and Health, and the entire assisted reproductive technology team at the CDC.
There have also been local impacts in communities due to federal layoffs. ABC News previously reported in March, the CDC was poised to send its lead ‘disease detectives’ to Milwaukee amid an ongoing lead crisis in schools, but the entire division was cut under sweeping HHS layoffs, leaving local health officials without help they were relying on.
Erik Svendsen, the director of the division that oversaw the CDC’s Childhood Lead Poisoning Prevention branch, previously told ABC News that what’s happening in Milwaukee is a real world example of the impact of their absence.
“Without us, there is no other unit at the federal level that is here to support them in doing what they need to do,” he said.
On Monday, officials in Milwaukee announced two additional schools are closing due to this crisis
Despite Kennedy saying some programs and employees would soon be reinstated because they were mistakenly cut, it still leaves thousands of federal employees without jobs.
Scientists have also been laid off at NASA, the Environmental Protection Agency, the Department of Agriculture and the National Oceanic and Atmospheric Administration.
Cohen said these firings have put studies on hold and have greatly reduced the capacity of the federal government to review research.
“Scientists inside agencies, whether they’re environmental scientists or medical scientists or people focusing on vaccines or drugs, are being fired, and so some of the research capacity in Washington, in the federal government is being eliminated, and also their ability to judge proposals from universities,” he said.
“The only place I haven’t seen [firings] happen yet are the laboratories,” Cohen added.
Cuts that are currently proposed or have already been implemented include the elimination of the Office of Infectious Disease and HIV Policy, created by Brett Giroir, the former U.S. assistant secretary for health.
Giroir, who helped convince Trump in his first term to set a goal to end the HIV epidemic in the U.S., wrote in a post on social media last week that the president could ruin his legacy and mission with such cuts.
Canceling research grants, funding cuts to universities
Millions of dollars’ worth of grants have been terminated at the National Institutes of Health related to studies involving LGBTQ+ issues, gender identity and diversity, equity and inclusion (DEI) because they do not “effectuate” the “priorities” of President Donald Trump’s administration, according to copies of termination letters sent to grant recipients and viewed by ABC News.
Dr. Harold Varmus, a cancer researcher at Weill Cornell Medicine in New York City and former director of the NIH, said these terminations are “detrimental” because they may be affecting people in the middle of clinical trials, or affecting the early stages of experimental work.
Research projects focusing on minority populations have major benefits, Varmus noted.
“The purpose of health research in this country is to address problems faced by everybody and to explore every facet of a population that may affect their health,” he said. “To single out certain categories of individuals who would not be appropriate to study seems ludicrous to me … one of the great strengths of America is that we are diverse.”
Universities have also been threatened with funding cuts — or have seen funds frozen — if they don’t fulfill their obligations under Title VI of the Civil Rights Act to protect Jewish students on campus and to end race-based programs.
Cohen believes universities are at odds with the administration because some on the political right view universities as “left wing.” By “weakening the finances of universities, they can force them to change the ideologies that they believe are being promoted in the classrooms,” he argued.
The problem with this idea, according to Cohen, is that the administration’s actions are hurting the least ideological parts of universities, such as engineering schools or medical centers. At Columbia, for example, several institutes and centers are conducting Alzheimer’s research, he said.
“Those are the places that are being attacked,” Cohen said. “It’s pretty ironic, but the greatest danger, actually, is that one of America’s fundamental economic strengths is the creativity and the innovation of our scientists, and that is now under attack by the Trump administration.”
Questioning safety, efficacy of vaccines
Kennedy has shared vaccine skepticism in the past and has continued to do so as HHS secretary.
In the wake of several ongoing measles outbreaks and over 800 cases so far this year, Kennedy has shared contradicting views about vaccines.
In a post on X on April 6, he said that “most effective way to prevent the spread of measles” is to receive the measles, mumps, rubella (MMR) vaccine. However, in a post later that evening, he said more than 300 children have been treated with an antibiotic and a steroid, neither of which are cures for measles.
Dr. Peter Hotez, a professor of pediatrics and molecular virology at Baylor College of Medicine in Houston, said the statements Kennedy has made in support of the MMR vaccine are “half-hearted.”
“The reason I say ‘half-hearted’ or insufficient is because each time he talks about using the MMR vaccine, he qualifies it,” Hotez told ABC News. “He then draws this false equivalency between either getting the MMR vaccine or this cocktail of interventions that would do absolutely nothing.”
Last month, HHS confirmed that the CDC will study “all the potential culprits” including whether vaccines cause autism despite numerous existing studies already showing there is no link.
Hotez said epidemiologic studies show that children who received either the MMR vaccine, or vaccines containing thimerosal — a compound used as a preservative in vaccines — are not more likely to be diagnosed autism than kids who didn’t receive those vaccines.
Additionally, Hotez said about 100 genes have been identified that are involved in the development of autism, many by the Broad Institute at Harvard and the Massachusetts Institute of Technology.
He believes rising rates of autism diagnoses are likely due to wider testing and expanding diagnostic criteria. Hotez added that there could be an environmental exposure influencing autism genes, but that it’s not vaccines.
In 2017, he discussed with Kennedy an investigation looking at “about half a dozen chemical exposures” in early pregnancies but Kennedy “had no interest,” according to Hotez, who later documented these conversations in a book he published in 2018.
“He apparently seems to not understand the science or doesn’t care about the science. He’s got his fixed beliefs and doesn’t want to let any of the facts or scientific findings get in the way of his fixed belief,” Hotez said. “And it’s completely irresponsible having someone like that as Health and Human Services secretary.”
Claims around antidepressant use
Earlier this year, Trump issued an executive order to study the use of several medications including antidepressants and antipsychotics.
The order called for the formation of the “Make America Healthy Again” commission — to be chaired by Kennedy — with an aim to understand chronic diseases.
Among the goals of the commission is to “assess the prevalence of and threat posed by the prescription of selective serotonin reuptake inhibitors, antipsychotics, mood stabilizers, stimulants, and weight-loss drugs.”
Dr. Joseph Saseen, associate dean for clinical affairs and a professor in the departments of clinical pharmacy and family medicine at the Skaggs School of Pharmacy and Pharmaceutical Sciences at the University of Colorado, said there are plenty of studies and analyses in the medical literature looking at the prevalence of SSRIs.
“We have an overwhelming amount of information,” he told ABC News. “These medicines, particularly SSRIs, are the most frequently prescribed antidepressants for patients with major depressive disorder. There is a plethora of information evaluating efficacy in a broad range of patient populations for which these medicines are indicated.”
Saseen says these medications do have side effects, just like any drug, but the benefits significantly outweigh the risks for most people in the general population who have major depressive disorder and anxiety disorders.
Kennedy has also falsely linked the use of antidepressants to school shootings and claimed during his Senate confirmation hearings that members of his family had a harder time stopping SSRI use than heroin use.
Experts have said there is no evidence that equates ending the use of antidepressants to ending the use of heroin or to suggest that people on SSRIs are more likely to be violent.
Saseen said it’s reasonable to question scientific research, either to reaffirm or dispute findings, but it must be done following the scientific method.
“Question it the real way, not the cowardly way,” he said. “The cowardly way is labeling things as threats or as bad without taking a scientific approach. The key is you need to use appropriate methodologies, not vocal inflections and very triggering and polarizing words to create an uprising.”
ABC News’ Dr. Jade Cobern, Cheyenne Haslett, Will McDuffie and Sony Salzman contributed to this report.
(WASHINGTON) — The U.S. Centers for Disease Control and Prevention is closely monitoring an unknown disease that has killed dozens in the Democratic Republic of Congo, the agency said in a statement on Monday.
“CDC is monitoring the situation closely and engaging with DRC officials on what support the agency can offer,” the agency’s spokesperson said.
At least 1,096 people have been sickened and 60 people have died from the disease, the World Health Organization said Thursday in its most recent update.
This is the third time in the past few months officials have identified increases in illness and deaths in a different area of Congo, triggering “follow-up investigations to confirm the cause and provide needed support,” the WHO said in a statement on Thursday.
For example, there was a separate report of an unknown disease in December of last year in the central African country that was later attributed to illnesses from malaria and respiratory illnesses.
The symptoms for this latest cluster of disease include fever, headache, chills, sweating, stiff neck, muscle aches, multiple joint pain and body aches, a runny or bleeding from the nose, cough, vomiting and diarrhea, the WHO said.
Initial lab tests have been negative for Ebola and Marburg virus disease, the WHO said.
Around half of samples tested have been positive for malaria, which is common in the area, according to the WHO. Tests continue to be carried out for meningitis, and officials said they are also looking into food and water contamination.
The WHO said it has delivered emergency medical supplies, including testing kits and “developed detailed protocols to enhance disease investigation.”
“The WHO is supporting the local health authorities reinforce investigation and response measures, with more than 80 community health workers trained to detect and report cases and death,” the organization said.
