JONATHAN M. METSCH, Dr.P.H. – Tracking Emerging Public Health Challenges – August 20, 2026 – MEASLES
State health officials also have warned of recent measles activity in neighboring states and regions, including New Jersey and Pennsylvania, potentially increasing the risk of additional exposures.
Recent measles cases have been reported by local health officials in several upstate counties, including Allegany County and Seneca County.” (2)
“If a person who is not immune — that is, they’ve never had measles and they’ve never been vaccinated — if they come in contact with someone who has measles in the same room, there is a 90% chance or higher that they will get measles,” said Dr. Paul Graman, an epidemiologist at Strong Memorial Hospital.
The Centers for Disease Control and Prevention declared measles eliminated in the United States in 2000, but dropping vaccination rates are now threatening that status.
According to Graman, public health has become the victim of its own success. He said because the measles virus had all but disappeared for decades, some people question the need to get vaccinated.
“Having the attitude that, ‘I’m protected or not protected’ or ‘I don’t care,’ or ‘I’ve never seen measles,’ how are you going to feel if you get measles, and then someone in your school who can’t be vaccinated, a child, gets a serious case of measles, and it could have been prevented?” he asked. (3)
“Pockets of low vaccination rates in some schools help explain why measles outbreaks have been climbing in the U.S., even when county-level vaccination numbers – the data policymakers consult – appear high enough to provide community protections.
A new study, published Aug. 18 in Nature Medicine, helps reveal why measles, which was declared eliminated in the U.S. in 2000, increased to more than 3,500 cases in 2025-26.
The rise began prior to the COVID-19 pandemic but was made worse by it, largely due to vaccine hesitancy, a surge in vaccine misinformation on social media and vaccine exemption policies that vary across states.
In the study, the researchers collected publicly available county, school district and school-level data of measles, mumps and rubella (MMR) vaccinations and ran it through a mathematical model that translated vaccination coverage into transmission risk.
They found that a new case of measles could spread at a school that had children who were unvaccinated or had missed one of the two recommended MMR doses. These risks, however, appeared largely invisible when looking at statewide and county-level MMR coverage, because in aggregate, vaccination rates can remain near the 95% herd immunity threshold known to protect a population from wider outbreaks.
The data revealed that the average percentage of unprotected students across the country roughly doubled from 5% to nearly 10% following the pandemic. The study highlights the need for more detailed data to understand the true risks posed by measles.”
“Now we’re in a situation where, given the very heterogenous and low vaccine coverage in places, there is a possibility that an outbreak will become a big, localized outbreak after an introduction, which is what we see,” Bento said.
Outbreaks in 2025 and 2026 in Texas, Arizona, New Mexico and South Carolina revealed the same epidemiological pattern, where MMR vaccination rates at the county level looked reassuring, while school-level clusters of unvaccinated children had silently pushed local transmission risks above that epidemic threshold. (4)
“Public health experts have been quick to condemn an executive order from President Donald Trump aimed at upending childhood vaccinations in the U.S., but the biggest obstacles may be the unprecedented financial and logistical challenges it would impose on parents, health providers and drugmakers.
Monday’s announcement by the Republican president calls for separating combination shots — including the measles, mumps and rubella, or MMR, vaccine — into separate injections. Appointments for that and other vaccinations should be spaced out whenever possible, the order states.
To accomplish that, drugmakers would need to revive a slate of individual vaccines that have not been widely used in the U.S. for decades. They would also have to build new manufacturing plants capable of producing millions more vaccine doses than the nation currently uses.
For parents, unbundling the MMR vaccine and spacing out the shots would mean returning to the doctor’s office many more times than is currently needed. Those appointments could also strain pediatricians who typically administer the shots, while driving up costs tied
Studies in the U.S. and other countries have shown that combination vaccines increase the likelihood that children will be fully protected from infectious diseases before starting school.
“We do things that are less convenient and more expensive if there’s a good reason to do it,” said Dr. Anna Durbin, of the Johns Hopkins Bloomberg School of Public Health. “There is no good justification for this. I think it’s very bad public health policy.”” (5)
“At a time when measles and other potentially deadly diseases are spreading, more American children are receiving exemptions allowing them to attend school without the routine childhood shots that can protect against those illnesses.
Roughly 4 percent of kindergartners in the United States were given a nonmedical exemption for at least one vaccine during the 2025-26 school year, an 18 percent jump from the previous year, according to new data released on Monday by the Centers for Disease Control and Prevention. That rise, the largest annual increase recorded in more than a decade, comes as a growing number of states look to loosen vaccine mandates or even do away with them entirely.
Exemption rates varied dramatically by state. While all states allow students to opt out of vaccine requirements for certain medical conditions, some also allow exemptions for religious or personal reasons.
In Utah, which has some of the most relaxed laws around school vaccine requirements, nearly 13 percent of kindergartners had a religious or personal exemption for at least one routine shot. The state is also in the midst of a monthslong measles outbreak that has infected more than 700 people. New York, which stopped allowing parents to opt out for religious reasons in 2019, reported no non-medical exemptions.
The new data has deepened concern among public health experts that American communities are losing the levels of immunity needed to protect against a number of highly contagious illnesses.” (6)
“Rising measles cases mean people getting infected are at risk of serious health consequences, Bowdish pointed out.
Measles — which spreads through the air when an infected person breathes, coughs or sneezes — can cause fever, cough, runny nose, conjunctivitis and rash, and may lead to serious complications, including pneumonia, encephalitis, blindness and death, according to the WHO.
Measles can also lead to lost pregnancies, hospitalizations for kids with long-term health issues and “horrible” neurological consequences, Bowdish noted.
She said factors and systematic failures contributing to the increase in measles cases in Canada include:
The lack of a national vaccine registry in Canada, which makes it difficult for people to track their vaccination status.
The family doctor “crisis” that limits families’ access to vaccinations not available at pharmacies.
School-based mandatory vaccination rules sabotaged by what she called “loosey-goosey” exemption rules that have allowed unvaccinated kids to spread the virus.
Stretched public health agencies without the resources to do community outreach to reach people skeptical of vaccines.” (7)
“At a press conference in Bakersfield on Thursday, Health and Human Services Secretary Robert Kennedy Jr. was asked what the executive order means for families.
“The practicality is that the states will be getting the best medical and scientific advice that is available. Medically and scientifically available,” Kennedy said.”
“Kennedy said people have lost trust in regulatory agencies and have looked to other countries for vaccine recommendations.
“The president asked us to look at what other countries are doing where they don’t have mandates and yet they have enormous coverage. People trust their agencies and we wanted to make sure the public was getting the most scientific evidence,” Kennedy said.” (10)
“Setting aside Kennedy’s long history of maligning vaccines as potentially dangerous, Paul Offit, director of the Vaccine Education Center and attending physician in the Division of Infectious Diseases at Children’s Hospital of Philadelphia, argues that Kennedy hasn’t done enough as HHS secretary to encourage vaccination.
“He’s the number one public health official in this country. . . . He should hold a press conference every day, looking at the camera and saying, ‘Please vaccinate your children,’” Offit told National Review. “This is a preventable disease. The fact that children are once again dying in the United States is unconscionable.”
Kennedy has held press conferences to discuss issues ranging from advances in nutrition and medical education to fighting health-care fraud and autism, but he has not held a conference exclusively, or even in large part, on the U.S. measles outbreak.
“We don’t wait two years to react to a measles epidemic and we should not for any kind of infectious disease — we shouldn’t have to do that for diabetes or autism,” Kennedy said.
When asked about the outbreak in March 2025 by Fox News host Sean Hannity, Kennedy said the MMR vaccine wears off over time, leaving many older Americans “essentially unvaccinated.” He said he grew up at a time when everybody came down with the measles and received “lifetime protection against measles infection” through active natural immunity, and the vaccine doesn’t do that. The vaccine, Kennedy said, “does not appear to provide maternal immunity;” he added, “it used to be that very young kids were protected by breast milk.”” (8)
“Health officials in California are defending the traditional childhood vaccination schedule against efforts by the Trump administration to weaken it.
The longstanding childhood vaccine schedule is safe, California’s top health official said, and continues to be recommended by the American Academy of Pediatrics — the nation’s leading group for pediatricians — as well as the other states in the West Coast Health Alliance: Hawaii, Oregon and Washington.
“They’re safe. They’re important for kids to be thriving and healthy in schools,” Dr. Erica Pan, director of the California Department of Public Health and the state public health officer, said of vaccines. And she credited California’s robust vaccine requirements as a condition of enrollment for schoolchildren as a reason why the state so far has kept a lid on the huge outbreaks of measles seen in other parts of the nation.” (8)
“The U.S. recently reached a grim milestone: As of July 23, more measles cases have been reported to the Centers for Disease Control and Prevention than in any year since 1991. It took less than seven months to blow past the three-decade high recorded last year.
This potentially deadly disease is easily prevented. Shots are widely available and, in many cases, free. Still, since the beginning of last year, more than 4,850 people here have been infected, and three have died. Among them were two unvaccinated girls in West Texas whose deaths made national headlines.
It may feel like the continuous stream of cases is just the way things are now. But it is dangerous to shrug off the resurgence of measles. In a story I reported earlier this year, I showed what’s happened in parts of the world that have let their guard down to vaccine-preventable diseases. My reporting found that long-forgotten scourges roared back, killing and disabling children. Even countries that made what seemed like subtle changes to immunization policies suffered disastrous consequences years later.
Babies were born blind, deaf and with intellectual disabilities because their mothers caught rubella in the early weeks of pregnancy. Parents saw why diphtheria used to be known as “the strangling angel of children.” Doctors told me they couldn’t undo the damage when these horrors returned. Modern medicine can do a lot of things, but it can’t reverse paralysis from polio.
The story also showed how Robert F. Kennedy Jr., the nation’s top health official, and President Donald Trump have been transforming a government that for decades promoted the lifesaving benefits of shots into one that sows doubts about their safety. Last week, the president issued another executive order that’s sure to fuel further hesitancy about the shot that has protected children from measles, mumps and rubella for decades.
It’s a sharp departure for a government that, since the 1960s and with bipartisan support, built vaccination programs that shielded kids from deadly and disabling diseases. Federal and state health leaders strengthened those policies based on lessons learned from measles outbreaks. That’s because measles, among the most contagious diseases in history, is almost always the first vaccine-preventable disease to strike when immunization rates fall.” (1)
1.Measles Used to Be in Our Rearview Mirror. Now Cases Are Reaching Record Highs., by Patricia Callahan, https://www.propublica.org/article/measles-cases-vaccines
2.Measles cases reported across NY as school year approaches. Here’s what to know, by New York Connect Team, https://www.democratandchronicle.com/story/news/2026/08/20/new-york-measles-cases-2026-what-to-know/91383037007/
3.Six confirmed measles cases, 14 presumed infected across upstate NY, By Beth Adams, https://www.wxxinews.org/local-news/2026-08-19/5-confirmed-measles-cases-14-presumed-infected-across-upstate-ny
4.County vaccination data masks measles risk, By Krishna Ramanujan, Cornell Chronicle, https://news.cornell.edu/stories/2026/08/county-vaccination-data-masks-measles-risk
5.U.S. President Donald Trump signs an executive order in the Oval Office at the White House in Washington, By Matthew Perrone, https://www.pbs.org/newshour/health/trumps-vaccine-order-would-require-millions-of-individual-shots-last-used-decades-ago
6.More U.S. Parents Opting Children Out of Vaccine Requirements, C.D.C. Reports, By Teddy Rosenbluth, Dani Blum and Francesca Paris, https://www.nytimes.com/2026/08/17/well/vaccine-exemptions-rates.html?smid=nytcore-ios-share
7.Surge in measles cases risks ‘horrific’ health consequences: immunologist, by Paul Forsyth, https://www.cbc.ca/news/canada/hamilton/measles-surge-in-infections-horrific-health-consequences-9.7309166
8.Examining RFK Jr.’s Role in the Measles Outbreak, By Kaitlyn Kiepert, https://www.nationalreview.com/news/examining-rfk-jr-s-role-in-the-measles-outbreak/
9.California defends childhood vaccination schedule against Trump efforts to weaken it, by Rong-Gong Lin II, https://www.latimes.com/california/story/2026-08-15/california-defends-childhood-vaccination-schedule-against-trump-efforts-to-weaken-it
10.Kennedy in Bakersfield: States will get best science as Kern reports measles cases, by Jake Shriner, https://bakersfieldnow.com/news/local/kennedy-in-bakersfield-states-will-get-best-science-as-kern-reports-measles-cases
curated by Jonathan M. Metsch, Dr.P.H.
Clinical Professor of Environmental Medicine, Icahn School of Medicine at Mount Sinai