Pennsylvania has confirmed a fourth measles-related death in 2026, making this the state’s deadliest measles outbreak in 35 years and the most measles deaths recorded in the United States in a single year since 1992. The latest death, an unvaccinated 18-year-old from Mifflin County, was announced by the state Health Department on September 15, 2026. All four deaths have occurred within the past month as Pennsylvania’s outbreak continues to grow, and the crisis has also become the center of a heated political dispute between state officials and federal health leadership.
Here’s what’s confirmed, what’s disputed, and what public health officials want Pennsylvania residents to know — including how the outbreak is being tracked, why vaccination rates have fallen in some communities, and what steps state health officials recommend for anyone concerned about exposure.
The Four Confirmed Deaths
According to the Pennsylvania Department of Health, the four measles-associated deaths reported so far in 2026 are, in order of when they were reported to the public:
- Two infants in Lancaster County, who died last month. One infant had a serious genetic condition known as Amish lethal microcephaly; the Lancaster County coroner’s office confirmed measles caused or contributed to that death.
- A 40-year-old woman from Jefferson County, who had asthma and severe lung disease, and died in mid-September.
- An 18-year-old from Mifflin County, whose death was announced September 15. The county coroner determined the cause of death to be acute disseminated encephalomyelitis (ADEM), a rare and severe neurological complication that can follow a measles infection.
State health officials confirmed that none of the four people who died had been vaccinated against measles.
How Big Is the Outbreak?
As of mid-September 2026, Pennsylvania has confirmed nearly 700 measles cases across 38 counties this year, with 133 people hospitalized. Nationally, the CDC has confirmed 3,294 measles cases and 267 hospitalizations, with 95% of cases linked to identifiable outbreaks. The scale of Pennsylvania’s outbreak specifically has led state officials to describe it as the worst in the country.
For context on how unusual this is: the United States declared measles eliminated in 2000, meaning the disease was no longer considered to be in continuous, year-round circulation domestically. The current surge — driven largely by falling vaccination rates — has been significant enough that international health officials are scheduled to meet in November 2026 to determine whether the U.S. and Mexico have lost their official measles-free status, a designation both countries have held for roughly a quarter-century and one that carries real implications for how the disease is monitored and funded going forward.
A Political Dispute Over Counting Deaths
Beyond the outbreak itself, Pennsylvania’s measles deaths have become entangled in a public dispute over how the federal government tracks and reports them. As of mid-September, the CDC had not counted any of Pennsylvania’s four measles deaths in its official national tally. The agency’s website states it does not have death records from 2026 confirming measles as the underlying cause in these cases — a departure from how the CDC has traditionally accepted state health department death reports.
CDC Director Dr. Erica Schwartz said Pennsylvania, unlike other states reporting measles deaths, had not provided the documentation the agency typically requires. Pennsylvania Governor Josh Shapiro pushed back sharply, accusing Health and Human Services Secretary Robert F. Kennedy Jr. of personally intervening in what he described as an otherwise routine administrative process. Shapiro said the move appeared designed to avoid data that didn’t fit a preferred narrative on vaccine skepticism, and he has repeatedly called on Kennedy to stop what he characterizes as the spread of misinformation about vaccine safety from within the federal health apparatus.
Kennedy has responded publicly to Shapiro’s criticism, though the two sides remain at odds over both the specific death count and the broader messaging around vaccination during the outbreak. The dispute has added a layer of political tension to what is, at its core, a public health emergency playing out in real time across dozens of Pennsylvania counties — and it has drawn national attention from public health researchers concerned that disputes over data transparency could, in the long run, further erode public trust in vaccination guidance at exactly the moment officials say clear, consistent messaging matters most.
Why Measles Is Dangerous
Measles is one of the most contagious diseases known, capable of spreading through the air and lingering in a space for up to two hours after an infected person has left. For most people, it causes fever, cough, runny nose, and a characteristic rash — but complications can be severe, particularly in young children, infants, and people with weakened immune systems or underlying health conditions.
The complications reported in Pennsylvania’s four deaths illustrate the range of ways measles can turn fatal: severe illness in a medically vulnerable infant, complications in an adult with pre-existing respiratory disease, and acute disseminated encephalomyelitis, a rare but serious inflammation of the brain and spinal cord that can follow infection. According to public health data, roughly 1 in 1,000 children who contract measles will develop encephalitis, and the disease can be fatal in a small but real percentage of cases, particularly among the unvaccinated.
Why Vaccination Rates Have Fallen
Public health officials have pointed to several converging factors behind Pennsylvania’s outbreak and the broader national resurgence of measles: an increase in parental vaccine waivers for school-entry requirements, uneven access to routine pediatric healthcare in some communities, and what officials describe as a rise in vaccine misinformation and hesitancy. Some of the hardest-hit counties in this outbreak — including Lancaster and Mifflin — include communities with historically lower vaccination rates.
The measles, mumps, and rubella (MMR) vaccine, administered in two doses, is highly effective — public health officials cite approximately 97% lifetime protection following the full two-dose series. Public health experts widely regard high community vaccination coverage (generally around 95%) as necessary to maintain “herd immunity” and prevent outbreaks like the one currently unfolding in Pennsylvania.
What State Officials Are Telling Residents
Pennsylvania Secretary of Health Dr. Debra Bogen has expressed condolences to the families affected by the outbreak while continuing to urge residents to get vaccinated. The state Health Department has set up a dedicated resource for the public: anyone who believes they may have been exposed to measles, or who is experiencing symptoms, is urged to contact their healthcare provider or call the department’s toll-free hotline at 877-PA-HEALTH (877-724-3258).
State officials have emphasized that vaccination remains the most effective way to prevent both infection and the kind of severe complications behind the four deaths reported so far this year.
How Pennsylvania’s Outbreak Compares Nationally
Pennsylvania’s four deaths in 2026 already exceed the total measles deaths recorded nationwide in all of the previous year, when the U.S. reported three measles deaths — two in Texas and one in New Mexico. Other states have also seen active outbreaks in 2026, including Indiana, Kansas, Michigan, Oklahoma, Ohio, Texas, and New Mexico, part of a broader national resurgence that has pushed U.S. case counts to their highest levels in years.
The pattern nationally has followed a similar trajectory to what’s been observed in Pennsylvania: outbreaks concentrated in communities with lower vaccination coverage, disproportionately affecting unvaccinated children and, in the most severe cases, leading to hospitalization or death.
Timeline of Pennsylvania’s 2026 Measles Outbreak
- Early 2026: Measles cases begin rising across multiple Pennsylvania counties as part of a broader national resurgence.
- Late August 2026: The state announces its first two measles-associated deaths — two infants in Lancaster County. The CDC declines to count these deaths in its national tally, citing insufficient documentation.
- Mid-September 2026 (weekend): A third death is reported: a 40-year-old woman from Jefferson County with underlying respiratory conditions.
- September 15, 2026: The state confirms a fourth death — an 18-year-old from Mifflin County — and formally confirms the third death from Jefferson County in the same announcement. Governor Shapiro publicly criticizes HHS Secretary Kennedy over the CDC’s continued refusal to count Pennsylvania’s deaths.
- Ongoing: Nearly 700 confirmed cases across 38 counties, with state and federal officials continuing to dispute how the outbreak’s death toll should be tracked and reported.
What Are the Symptoms of Measles?
According to public health guidance, measles symptoms typically begin seven to fourteen days after exposure and follow a fairly predictable pattern:
- High fever, often exceeding 104°F
- Cough, runny nose, and red, watery eyes (conjunctivitis)
- Koplik spots — small white spots that can appear inside the mouth a few days after symptoms begin
- A red, blotchy rash that typically starts on the face and spreads downward to the rest of the body, usually appearing three to five days after the first symptoms
Measles is considered contagious from about four days before the rash appears until four days after, meaning a person can spread the virus before they — or anyone around them — realizes they’re sick. The virus spreads through respiratory droplets when an infected person coughs or sneezes, and it can also remain suspended in the air or on surfaces for up to two hours after an infected person has left a room.
Who Is Most at Risk of Severe Complications
While measles can cause serious illness in anyone who isn’t immune, certain groups face a substantially higher risk of severe outcomes:
- Infants under 12 months, who are typically too young to have received their first MMR dose and rely on community immunity for protection.
- Children under 5 more broadly, who account for a disproportionate share of severe complications nationally.
- People with underlying health conditions, including chronic respiratory or immune-related conditions, as illustrated by the Jefferson County case involving a woman with asthma and severe lung disease.
- People with genetic or congenital conditions that compromise their overall health, as in the case of the Lancaster County infant with Amish lethal microcephaly.
- Pregnant women, who face elevated risk of complications including premature birth.
Public health officials have repeatedly emphasized that the pattern seen in Pennsylvania’s four deaths — all involving unvaccinated individuals, several with additional vulnerabilities — is consistent with what’s typically observed in measles outbreaks nationally and historically. Before widespread vaccination, measles-related encephalitis and other severe complications were a leading cause of preventable childhood disability and death in the U.S., which is part of why the disease’s return to this scale has drawn such sustained attention from public health researchers and state officials alike.
The Broader National Vaccine Policy Context
Pennsylvania’s outbreak and the dispute over its death count haven’t unfolded in a vacuum. They come amid a broader national debate over vaccine policy under the current administration. Health Secretary Robert F. Kennedy Jr., a longtime vaccine skeptic before joining the administration, has faced sustained criticism from public health officials and Democratic state leaders for what they describe as efforts to sow doubt about established vaccine safety data, while also reportedly scaling back federal funding for local vaccination outreach efforts.
Kennedy previously drew criticism earlier in 2026 for downplaying the severity of a separate, earlier measles outbreak centered in Texas, which also resulted in the deaths of two unvaccinated elementary-school-aged children, as well as an unvaccinated adult in New Mexico. That outbreak, like Pennsylvania’s, was concentrated in communities with lower-than-average vaccination coverage.
The clash between Pennsylvania’s governor and the federal health secretary over how to count and communicate about measles deaths reflects this larger tension — one that has made an already difficult public health response more complicated to navigate for state officials trying to communicate clearly with residents about real, immediate risk.
How Outbreaks Like This Get Declared and Tracked
Public health agencies generally define an “outbreak” as three or more confirmed cases linked to a common source or transmission chain. Once an outbreak is declared, state and local health departments typically ramp up contact tracing, targeted vaccination clinics, and public communication campaigns aimed at containing further spread — particularly in schools, religious communities, and other settings where unvaccinated individuals may cluster.
Pennsylvania’s Department of Health has been providing regular public updates throughout 2026 as case counts climbed across the state’s 38 affected counties. The dispute with the CDC over officially counting the state’s deaths adds a layer of complexity to that reporting process, since federal case and mortality counts are often used by researchers, media, and other states to benchmark the overall severity of an outbreak nationally.
What Parents and Communities Should Know
For parents specifically, public health officials continue to recommend following the standard childhood MMR vaccination schedule: a first dose at 12 to 15 months of age, and a second dose between ages 4 and 6 — the schedule associated with the roughly 97% lifetime protection rate cited by health officials. Infants younger than 12 months, who are generally too young for their first dose, depend heavily on high vaccination rates in the broader community to reduce their exposure risk, which is part of why public health officials frame vaccination as a community responsibility rather than a purely individual choice.
For anyone uncertain about their own or their child’s vaccination status, healthcare providers can typically check immunization records or administer a titer test to confirm immunity. Pennsylvania’s Health Department has directed residents with questions or exposure concerns to its dedicated hotline rather than relying on informal guidance from social media or other unofficial sources — a point state officials have emphasized repeatedly given the amount of misinformation circulating around this and other recent outbreaks. Schools, daycare providers, and healthcare facilities in affected counties have also been coordinating with the Health Department on exposure notifications, underscoring how outbreak response extends well beyond any single household’s decisions.
A Brief History of Measles in the United States
Before a vaccine became available in 1963, measles was a near-universal childhood illness in the U.S., infecting an estimated 3 to 4 million Americans annually and causing hundreds of deaths and thousands of hospitalizations each year, primarily among children. Widespread vaccination campaigns following the vaccine’s introduction dramatically reduced case counts over subsequent decades, culminating in the disease being declared officially eliminated in the United States in 2000 — meaning continuous domestic transmission had been stopped, even though the virus could still occasionally be reintroduced by international travelers.
Since elimination, the U.S. has periodically experienced localized outbreaks, almost always traced back to unvaccinated communities and often triggered by an initial case introduced from abroad. The scale of the current 2026 outbreak — with Pennsylvania alone reporting more deaths than the entire country recorded in each of the past several years — represents one of the most serious tests of that elimination status since it was achieved a quarter-century ago.
The Earlier 2026 Texas Outbreak: A Preview of What Was to Come
Pennsylvania’s outbreak followed an earlier, high-profile measles outbreak centered in West Texas earlier in 2026, which ultimately spread to neighboring states including New Mexico, Oklahoma, and Kansas. That outbreak resulted in the deaths of two unvaccinated elementary-school-aged children near its epicenter in rural West Texas, along with an unvaccinated adult in New Mexico — deaths that, at the time, represented the first measles fatalities in the U.S. since 2015.
At the time, Secretary Kennedy faced criticism for publicly claiming during a televised Cabinet meeting that measles cases were “plateauing” nationally, even as case counts continued climbing well beyond what had been seen in the prior several years combined. Public health experts at the time warned that the virus was likely to continue spreading into other states with pockets of low vaccination coverage — a warning that, months later, appears to have been borne out by Pennsylvania’s own outbreak.
How This Compares State by State
As of mid-September 2026, states with active measles outbreaks — generally defined as three or more linked cases — include Pennsylvania, Texas, New Mexico, Oklahoma, Kansas, Indiana, Michigan, and Ohio. Pennsylvania’s outbreak stands out both for its overall case count (nearly 700 confirmed cases) and, more significantly, for its death toll, which state officials say makes it the worst measles outbreak of any state in the country this year.
The geographic spread of Pennsylvania’s outbreak is also notable: cases have been confirmed across 38 of the state’s 67 counties, suggesting transmission chains extending well beyond any single community or initial cluster, and complicating the state’s containment efforts compared to more geographically concentrated outbreaks elsewhere. Public health researchers note that this kind of dispersed spread, rather than a single tightly clustered event, is often harder to contain precisely because it requires coordinated response across many separate local health systems rather than one centralized effort.
How to Protect Yourself and Your Family
Public health officials consistently point to a small set of concrete steps that reduce individual and community risk during an active measles outbreak:
- Confirm vaccination status. Check your own and your children’s immunization records, or contact a healthcare provider to verify MMR vaccination history.
- Get vaccinated if you haven’t been. The two-dose MMR series remains the most effective protection available, and it’s not too late to catch up on missed doses.
- Watch for early symptoms. High fever, cough, red watery eyes, and the characteristic rash pattern described above are the key signs to watch for, particularly if you’ve had any potential exposure.
- Isolate if you suspect infection. Because measles is contagious before the rash even appears, anyone with symptoms consistent with measles should avoid contact with others — especially infants, pregnant women, and immunocompromised individuals — and call ahead before visiting a healthcare provider so the facility can take appropriate precautions.
- Use official resources. Pennsylvania’s Health Department hotline (877-PA-HEALTH) and official state and CDC websites remain the most reliable sources for updated case counts, exposure locations, and guidance, rather than relying on social media.
Key Terms Explained
- Herd immunity: The indirect protection from an infectious disease that occurs when a sufficiently high percentage of a population is immune, reducing the likelihood of sustained transmission even among those who aren’t vaccinated. For measles, this threshold is generally estimated at around 95% vaccination coverage.
- MMR vaccine: The combination vaccine that protects against measles, mumps, and rubella, typically given in two doses during childhood.
- Elimination status: A designation indicating a disease is no longer in continuous, year-round transmission within a country, though isolated outbreaks from imported cases can still occur.
- Acute disseminated encephalomyelitis (ADEM): A rare but serious inflammatory condition affecting the brain and spinal cord that can occur as a complication following a viral infection, including measles.
- Outbreak-associated case: A confirmed illness that has been epidemiologically linked to a specific chain of transmission, as opposed to an isolated, unconnected case.
Pennsylvania’s School Vaccination Requirements
Like most U.S. states, Pennsylvania requires children to be vaccinated against measles and other diseases to attend public school, but the state — like the majority of states — permits exemptions for medical, religious, and in some cases philosophical or personal-belief reasons. Public health researchers have pointed to a gradual rise in the use of these non-medical exemptions in certain Pennsylvania school districts and communities over the past several years as one contributing factor to the pockets of lower vaccination coverage now associated with several of the state’s hardest-hit outbreak counties.
State health officials have generally stopped short of calling for exemption policy changes in the midst of the active outbreak, instead focusing public messaging on encouraging voluntary vaccination and providing accessible testing and treatment resources through the Health Department’s hotline and local healthcare providers. Whether this outbreak prompts a broader legislative reexamination of Pennsylvania’s exemption rules — as has happened in other states following past outbreaks — remains an open question likely to play out over the coming months as case counts and the political dispute over data reporting both continue to develop.
Frequently Asked Questions
How many people have died from measles in Pennsylvania in 2026?
Four deaths have been confirmed by the Pennsylvania Department of Health as of September 15, 2026: two infants in Lancaster County, a 40-year-old woman in Jefferson County, and an 18-year-old in Mifflin County.
Were the people who died vaccinated against measles?
No. State health officials confirmed that none of the four individuals who died had been vaccinated against measles.
Why isn’t the CDC counting Pennsylvania’s measles deaths?
The CDC has said it lacks sufficient documentation to confirm measles as the underlying cause of death in these cases, a position Pennsylvania officials, including Governor Shapiro, have publicly disputed, alleging political interference in the reporting process.
How many measles cases are there in Pennsylvania right now?
As of mid-September 2026, Pennsylvania has confirmed nearly 700 measles cases across 38 counties, with 133 hospitalizations.
What should I do if I think I’ve been exposed to measles in Pennsylvania?
Contact your healthcare provider or call the Pennsylvania Department of Health’s toll-free hotline at 877-PA-HEALTH (877-724-3258) for guidance.
How effective is the measles vaccine?
Public health officials cite the two-dose MMR vaccine series as providing approximately 97% lifetime protection against measles.
When was the last time the U.S. had this many measles deaths in one year?
1992 was the last year the U.S. recorded four measles deaths. Last year, the country recorded three measles deaths nationwide.
Is measles still considered “eliminated” in the United States?
Measles was declared eliminated in the U.S. in 2000. The scale of the current outbreak has prompted international health officials to schedule a review in November 2026 of whether the U.S. and Mexico have maintained their measles-free status.
What were the earlier measles deaths in the U.S. this year?
Before Pennsylvania’s outbreak, an earlier 2026 outbreak centered in West Texas resulted in the deaths of two unvaccinated elementary-school-aged children, along with an unvaccinated adult in neighboring New Mexico.
Can adults get measles if they were vaccinated as children?
The two-dose MMR vaccine series provides approximately 97% lifetime protection, making breakthrough infections in fully vaccinated individuals uncommon, though not impossible. Anyone unsure of their vaccination history should consult a healthcare provider.
Why is there a dispute between Pennsylvania and the CDC over the death count?
Pennsylvania has reported four measles-associated deaths through its state Health Department, but the CDC says it lacks documentation to confirm measles as the underlying cause in its own national tally — a discrepancy Pennsylvania officials have publicly attributed to political interference from federal health leadership, a characterization the administration disputes.
The Bottom Line
Pennsylvania’s fourth measles death in a single month marks a somber milestone — the most measles deaths the U.S. has recorded in a year since 1992 — and underscores how quickly a largely preventable disease can turn severe in unvaccinated populations. Beyond the immediate public health emergency, the outbreak has also exposed a sharp political rift over how the federal government tracks and reports measles-related deaths, with Pennsylvania officials accusing federal health leadership of undercounting the toll. For residents, state officials’ guidance remains consistent: get vaccinated, and contact a healthcare provider or the state’s dedicated hotline if you believe you’ve been exposed.
With nearly 700 cases still active across 38 counties and the outbreak showing no clear signs of slowing, Pennsylvania’s experience is likely to remain a closely watched test case for how states respond to measles resurgence — both in terms of public health containment and in the broader political debate over vaccine policy playing out at the federal level. Public health officials across the country will likely be watching closely to see whether Pennsylvania’s case counts and death toll begin to plateau in the coming weeks, or whether the outbreak continues to grow as the state heads into the fall and winter months, when respiratory viruses typically spread more easily indoors.
This article is for informational purposes and is not a substitute for medical advice. If you believe you or a family member has been exposed to measles or are experiencing symptoms, contact a healthcare provider or the Pennsylvania Department of Health at 877-PA-HEALTH (877-724-3258).
Sources: CDC measles data, Pennsylvania Department of Health statements, and reporting from CNN, NBC News, ABC7, and the Associated Press.
