Measles Outbreak Turns Deadly as Pregnancy Infections Rise in Pennsylvania

WHO:

CIDRAP - Adam J. Ratner, MD, MPH, is a member of the American Academy of Pediatrics Committee on Infectious Diseases.

CNN - Dr. Matthew Ferrari is director of the Center for Infectious Disease Dynamics at Penn State University.

CNN - Dr. Remy Pasco is a research associate at the University of Colorado Boulder and has worked on an analysis estimating the scale of a Texas measles outbreak.

CNN - Dr. Debra Bogen is secretary of the Pennsylvania Department of Health; Dr. Erica Schwartz is CDC director.

CNN - Pennsylvania’s Amish and broader Plain community include a large population of unvaccinated adults.

CNN - Two infants infected with measles died in Pennsylvania; both were too young to receive the measles-mumps-rubella (MMR) vaccine.

NBC News - The Pennsylvania Department of Health issued an alert to doctors about measles infections in pregnant women and congenital measles.

WHAT:

Upper Michigan's Source - Three measles cases have been confirmed in Delta County, Michigan.

Upper Michigan's Source - The Delta & Menominee Counties health department said these are its first confirmed measles cases since 1989 and the first in Michigan’s Upper Peninsula in 2026.

Upper Michigan's Source - Up to 9 in 10 unprotected people exposed to measles may become infected; symptoms typically begin 7 to 14 days after exposure but can take up to 21 days.

Upper Michigan's Source - One measles vaccine dose provides about 93% protection; two doses provide roughly 97%.

CIDRAP - Pennsylvania said information about infant outcomes in measles-affected pregnancies cannot be released under state law.

CIDRAP - Pennsylvania’s health department said it would not label the Franklin County death measles-associated without evidence of measles infection and a positive laboratory test within the preceding 30 days.

CIDRAP - The state health department said congenital measles can range from asymptomatic infection to rash, multisystem disease, or death; treatment includes supportive care and, for symptomatic infants, vitamin A unless contraindicated.

CIDRAP - Asymptomatic infants born to mothers with active measles infection, defined as rash onset within 14 days of birth, could also receive immunoglobulin.

STAT - Katrine Wallace said acknowledging that most children recover could build credibility to explain why “most” is not enough when a safe, effective vaccine is available.

STAT - A CDC infographic warns that measles “isn’t just a little rash.”

STAT - More than 4,400 measles cases were reported in the United States this year, twice the 2025 total.

STAT - Measles vaccination rates declined from 2017 to 2024 in more than 1,600 US counties.

STAT - Before measles vaccination, the United States recorded roughly 48,000 measles-related hospitalizations and 500 deaths annually.

STAT - A 2025 KFF survey found that more than half of parents were “not too worried” or “not at all worried” about measles.

STAT - A 2019 study found that a sizable portion of children infected with measles experienced “immune amnesia,” losing a substantial portion of antibodies against other infectious diseases.

STAT - In a survey of more than 9,000 people across the United States, FrameWorks found that framing vaccines as benefiting the common good “marginally increases” belief in vaccine benefits.

CIDRAP - Pennsylvania reported that 66 pregnant women had contracted measles and at least six babies had been born with measles.

CIDRAP - A Canadian measles outbreak in 2025 involved 51 pregnant women; nine cases of congenital measles resulted, and one of those infants died.

CIDRAP - Pennsylvania’s measles dashboard listed 1,286 cases, including 109 reported in the past week.

CIDRAP - Pennsylvania said it was investigating a sixth reported death in Franklin County; it would not classify the death as measles-associated without evidence of measles infection and a positive laboratory test within the prior 30 days.

CNN - Pennsylvania’s outbreak was described as the largest and deadliest US measles outbreak in more than 30 years, with about 1,300 reported cases, five officially reported measles-associated deaths, and a sixth death under review.

CNN - Historical estimates indicate 1 to 3 deaths per 1,000 unvaccinated people who contract measles. Pennsylvania’s reported death rate is at least 1.5 times, and possibly up to 5 times, higher than average.

CNN - About two-thirds of Pennsylvania cases were among adults, and all but a few cases were in unvaccinated people. CDC data showed more than 60% of US cases over the preceding two years were among children or teens.

CNN - Hospitalization rates in the Pennsylvania outbreak were higher than expected; experts said severe cases can help estimate an outbreak’s true scale because not everyone seeks care or testing.

CNN - Pennsylvania’s health department warned of increased measles cases during pregnancy and rising concerns about congenital measles, identified for the first time in decades.

NBC News - The state health department warned doctors of a rise in congenital measles, a disease rarely, if ever, seen in the United States.

CNN - The CDC dashboard listed three measles-associated deaths, while Pennsylvania’s health department reported five. The CDC said the figure could change as information becomes available and that it was developing a standardized death case definition.

CNN - Bogen asked the CDC to acknowledge and list Pennsylvania’s five reported deaths, saying the omission “obscures the seriousness of this disease and the toll of measles across the U.S.”

WHERE:

CNN - The outbreak is in Pennsylvania; the affected community includes Amish and other Plain communities.

CNN - CDC data cited Texas as the location of a separate outbreak analyzed by Pasco.

NBC News - The Pennsylvania Department of Health issued its alert to doctors in Pennsylvania.

WHY:

ABC News - A computer model projected that delaying newborn hepatitis B vaccination until age 2 months could increase chronic infections by 19%, while shared clinical decision-making could increase them by 83% over 20 years compared with universal vaccination at birth.

ABC News - The model projected that 232,000 children could remain susceptible to hepatitis B at age 20 under universal birth-dose vaccination, compared with 474,000 if vaccination were delayed and 1.8 million under shared clinical decision-making.

CIDRAP - Adam J. Ratner said there is no denominator data for congenital measles; evidence largely comes from individual case studies and series, making it impossible to estimate how many pregnant women with measles will have an infant with congenital measles.

CIDRAP - Ratner said mild measles infections during pregnancy may go undetected, contributing to underreporting of prenatal measles.

STAT - Communication experts said acknowledging that most healthy children recover from measles could build credibility and trust; Peter Sandman said agencies should state this “forthrightly” and “repeatedly and emphatically.”

STAT - Patsy Stinchfield said communicators should emphasize that an average case of measles is “extremely miserable,” rather than focusing only on worst-case outcomes.

STAT - Elena Conis said measles was considered less serious in the first half of the 20th century when people faced diseases such as scarlet fever and typhoid fever.

CNN - Ferrari said unvaccinated adults may experience more severe measles complications than unvaccinated children.

CNN - Low protection among adults may leave infants more likely to be born without protective maternal antibodies. Ferrari said antibodies from vaccination or infection are not being passed from women of reproductive age to babies.

CNN - Experts said the outbreak may be larger than official counts suggest because cases are difficult to estimate and some may be unreported. US measles data is limited because measles is no longer endemic.

CNN - Ferrari said the outbreak reflects an epidemiological shift, not a change in the virus’s biology; he also cited community vulnerabilities and a uniquely susceptible population that is unvaccinated and has gone decades without exposure.

HOW:

Upper Michigan's Source - Delta & Menominee Counties’ health department is investigating the cases with the Michigan Department of Health and Human Services and notifying potentially exposed people.

Upper Michigan's Source - The health department advises people with measles symptoms to call their healthcare provider before seeking medical care to reduce the risk of spreading the disease.

CIDRAP - Pennsylvania’s health alert advises women to receive the MMR vaccine before pregnancy; it is not recommended during pregnancy because it contains live virus.

CIDRAP - An unvaccinated pregnant woman exposed to measles has a six-day window to receive immunoglobulin therapy.

CIDRAP - Congenital measles is defined as infection in the last two weeks of pregnancy or first 10 days after delivery. CIDRAP also cited a 2021 French case series describing asymptomatic infants who tested positive more than 20 weeks after maternal infection.

CNN - A CDC Epi-Aid scientist was sent to Pennsylvania to assess the outbreak’s scale and trajectory and evaluate local vaccination efforts.

CNN - The Pennsylvania health department requested the Epi-Aid and later accepted it, with Bogen describing state and CDC staff as collaborating on the response.

CNN - Ferrari said investigating the outbreak requires “classic boots on the ground epidemiology,” including asking community members about recent health history and vaccination coverage.

(UPDATED October 22, 2026 09:06 UTC)

Pennsylvania is confronting the nation’s largest and deadliest measles outbreak in more than 30 years, with about 1,300 cases and five officially reported deaths. A sixth death is under investigation, though the state says it needs laboratory evidence to classify it as measles-related. The outbreak has disproportionately affected unvaccinated adults, including Amish and other Plain communities, and the state reports that 66 pregnant women contracted measles and at least six babies were born infected. Two infants died; both were too young for vaccination. Health officials have warned doctors about measles during pregnancy and congenital infections, whose effects can range from no symptoms to severe illness or death. Meanwhile, three cases have been confirmed in Michigan’s Delta County, the area’s first since 1989. Two vaccine doses provide about 97 percent protection, and more than 4,400 US cases have been reported this year.

(UPDATED October 22, 2026 08:05 UTC)

Pennsylvania’s measles outbreak has reached 1,286 reported cases, with 109 added in the past week, and the state is investigating a sixth death. Five measles-associated deaths have been reported by Pennsylvania, although the CDC dashboard lists three; the agencies are working toward a standardized definition. The outbreak has also involved 66 pregnant women, and at least six babies have been born with measles. Two infants have died; both were too young for vaccination. The state has alerted doctors to congenital measles, which can range from no symptoms to severe disease or death. Officials advise women to get the MMR vaccine before pregnancy, since it is not recommended during pregnancy. About two-thirds of Pennsylvania cases are among adults, and nearly all cases are in unvaccinated people. Experts warn the true scale may be higher, as some infections go undetected.

(UPDATED October 22, 2026 02:13 UTC)

Pennsylvania is facing the largest and deadliest U.S. measles outbreak in more than 30 years, with about 1,300 cases and five officially reported measles-associated deaths. A sixth death is under investigation, while state and federal figures differ: the CDC lists three deaths and says its count may change. The state says 66 pregnant women have contracted measles, and at least six babies were born with the infection; two infants have died. Health officials have warned doctors about measles during pregnancy and congenital infection. Most cases are among unvaccinated people, with adults accounting for about two-thirds. Experts say the true scale may be higher because some cases go undetected, and unvaccinated adults may face severe complications. A CDC response team is working with Pennsylvania to assess the outbreak and vaccination efforts. The state advises vaccination before pregnancy; the MMR vaccine is not recommended during pregnancy.

(UPDATED October 21, 2026 16:15 UTC)

Pennsylvania’s measles outbreak has reached about 1,300 cases, with 66 pregnant women infected and at least six babies born with measles. The state has officially reported five measles-associated deaths and is investigating a sixth, while the CDC dashboard lists three; Pennsylvania’s health secretary says the gap understates the toll. Two infants who died were too young for vaccination. Health officials have also warned doctors about rising infections during pregnancy and congenital measles, a disease rarely seen in the United States. Most cases are among unvaccinated people, and about two-thirds are adults, including members of Amish and other Plain communities. Experts say adult infections can be severe, and limited immunity may leave babies without protective antibodies. Pennsylvania advises vaccination before pregnancy, but not during it; exposed, unvaccinated pregnant women may receive immunoglobulin within six days. A CDC team is working with state officials to assess the outbreak and vaccination efforts.

(UPDATED October 21, 2026 13:14 UTC)

Pennsylvania is facing the largest and deadliest U.S. measles outbreak in more than 30 years, with about 1,300 reported cases, five reported deaths and a sixth under review. Most cases were among unvaccinated people, and health officials have warned doctors about measles during pregnancy and rare cases of congenital measles; two infants who were too young for vaccination have died. The state and CDC are working together to assess the outbreak and vaccination efforts, while Pennsylvania’s health secretary has urged the CDC to include the state’s reported deaths in its tally.