The Pennsylvania measles outbreak has reached 977 confirmed cases across 39 of the state’s 67 counties as of 2 October 2026, according to the Pennsylvania Department of Health, making Pennsylvania the hardest-hit state in the current US measles surge. The state also reports five measles-associated deaths and 195 hospitalisations since the outbreak began in late April, as reported by Fox 56. Officials say vaccination is rising, with more than 53,000 MMR doses given in September.
Key Takeaways
- The Pennsylvania measles outbreak stands at 977 confirmed cases in 39 counties as of 2 October 2026.
- 195 people have been hospitalised, nearly 20% of identified cases, and five measles-associated deaths have been reported.
- Only 4 of the 977 cases were in vaccinated people, and two doses of the MMR vaccine give about 97% protection.
- More than 53,000 MMR doses were given statewide in September, more than double the usual 25,000 a month.
- The outbreak is part of the largest US measles surge in more than 30 years, according to a public health expert quoted by CIDRAP.
What Is Measles?
Measles is a highly contagious viral infection that spreads through the air when an infected person coughs or sneezes. It typically causes fever, cough, runny nose, red eyes and a rash, and can lead to serious complications such as pneumonia and brain swelling, particularly in young children and in people with weakened immune systems. Symptoms can begin seven to 21 days after exposure, according to the state health department. Vaccination with two doses of the MMR (measles, mumps and rubella) vaccine is the main protection.
Pennsylvania Measles Outbreak at a Glance
| Measure | Figure |
|---|---|
| Confirmed cases | 977 across 39 counties (as of 2 October 2026) |
| Hospitalisations | 195 since late April, nearly 20% of cases |
| Deaths | 5 measles-associated deaths |
| Vaccinated cases | 4 of 977 |
| MMR doses, September | More than 53,000 (typical month about 25,000) |
| Pop-up clinics | 189 clinics, more than 5,600 doses |
| US total (28 September) | More than 3,600 cases in 45 states and DC |
Where the Pennsylvania Measles Outbreak Is Concentrated
Cases are spread across 39 counties, but a few account for most of them. In figures reported by ABC News for 28 September, when the state total was 903, Lancaster County in the southeast had the most cases at 363, followed by Mifflin County in central Pennsylvania at 105. Eleven counties were reported to have community transmission. CIDRAP lists Chester and Snyder counties among other affected areas. Both county figures have grown since then, so they should be read as a snapshot.
ABC News reported that the majority of cases were among people aged 25 to 49, with people aged 18 to 24 the second-largest group. Nearly one in five identified cases has needed hospital care, a rate higher than the roughly 9% hospitalisation rate CIDRAP reports for the United States as a whole.
Deaths and Severity
Pennsylvania has reported five measles-associated deaths. Earlier reporting by ABC News described four deaths: two unvaccinated adults, aged 18 and 40, and two infants too young to receive the vaccine. Details of the fifth were not available in the sources we reviewed. CIDRAP noted that the CDC had not yet confirmed any 2026 US deaths at the time of its report, because national confirmation can lag state reports. We covered the earlier report on measles-associated deaths in Pennsylvania in an earlier article.
Vaccination Response
The state health department says more than 53,000 MMR doses were administered in September, more than double a typical month of about 25,000, after more than 49,000 in August. State staff gave more than 5,600 doses at 189 pop-up clinics, and department nurses have provided more than 8,700 doses in 2026. The department says: “The best protection against measles remains getting fully vaccinated.”
The wider picture is less encouraging. ABC News cites CDC data showing kindergarten MMR coverage of 92.4% in 2025-26, down from 95.2% in 2019-20. Public health experts generally say coverage of about 95% is needed to prevent sustained spread, which is why falling coverage leaves pockets of vulnerable children.
National Context
ABC News reported more than 3,600 measles cases across 45 states and Washington DC as of 28 September. CIDRAP described 39 outbreaks nationally and quoted public health expert Jennifer Nuzzo, who said: “We are currently in the worst bout of measles that the United States has seen in more than 30 years.” South Carolina, which declared an earlier outbreak of 997 cases over in April, has also driven this year’s totals. We could not open the Reuters report that describes Pennsylvania as the centre of the surge, so we attribute that characterisation to the CIDRAP and ABC coverage cited here.
What People Should Do
The state health department advises anyone who may have been exposed to contact a health professional. Dr Alok Patel told ABC News: “If you’ve been exposed, it is important to talk to a healthcare professional, but don’t go into an urgent care or an ER because you may be inevitably spreading it to other vulnerable people.” Anyone with symptoms should call ahead before visiting a clinic. The department runs a hotline at 877-PA-HEALTH (877-724-3258). More guidance is available from the US Centers for Disease Control and Prevention (CDC).
Why It Matters Beyond Pennsylvania
Measles is a marker of vaccination gaps: it spreads wherever coverage slips, and it can return quickly. The Pennsylvania case shows how outbreaks last for months once established, which is relevant to other countries running vaccination programmes, such as the HPV vaccination drive in India. Infectious disease control is also on the international agenda, as with the Ebola outbreak in DR Congo and the BRICS call for joint disease surveillance.
What Is Not Yet Known
- Final size: the outbreak is still growing, and 977 is a count as of 2 October.
- Fifth death: age, county and vaccination status were not available in the sources we reviewed.
- Source of spread: public reports do not say how the outbreak started or which communities are driving transmission.
- National confirmation: the CDC had not confirmed the Pennsylvania deaths in the reports we reviewed.
Our Assessment
In our assessment, the Pennsylvania measles outbreak shows that high national averages can mask local gaps. The surge in vaccination is a positive response, but it comes after months of spread, and cases may keep rising while recently vaccinated people build immunity. Counts change daily, so readers should check the state dashboard for the latest figures.
Frequently Asked Questions
How many measles cases are there in Pennsylvania?
The state reports 977 confirmed cases across 39 counties as of 2 October 2026.
How many people have died?
Pennsylvania reports five measles-associated deaths.
Were the cases vaccinated?
Only 4 of the 977 cases were among vaccinated people, according to the state.
How effective is the MMR vaccine?
Two doses provide about 97% protection, according to the CDC and the state health department.
What are the symptoms of measles?
Typical signs are fever, cough, runny nose, red eyes and a rash, and symptoms can start seven to 21 days after exposure.
How we reported this: figures come from the Pennsylvania Department of Health as reported by Fox 56, with additional data from ABC News and CIDRAP. Counts change quickly and sources report on different dates. Last updated 3 October 2026. This article is for information only and is not medical advice; contact a health professional about symptoms or exposure.