Measles outbreak in Pennsylvania Amish communities
A major measles outbreak in Pennsylvania, concentrated in Lancaster County's Amish communities, has resulted in over 1,350 cases and five deaths.
Pennsylvania has recorded over 1,350 measles cases this year, with more than a third occurring in Lancaster County. Three measles-associated deaths have been recorded in Lancaster County and two in other Pennsylvania counties. The outbreak has spread beyond Amish communities to affect the wider public, a situation fueled by falling vaccination rates among both religious groups and the general population.
Vaccination gaps in communities
Lancaster County's kindergarten MMR vaccination rate of 88% falls below the 95% threshold needed for herd immunity. The state's overall kindergarten MMR vaccination rate has also declined, dropping to 93.2% last year from 95.2% in the 2019-2020 school year. Kindergarten vaccination rates have declined in every central Pennsylvania county since 2020.
Vaccination rates vary significantly within the Plain communities at the outbreak's epicenter. The Amish and Old Order Mennonite populations in Lancaster County total approximately 45,000 and 6,000 people respectively. A 2022 survey found about 3 in 10 Amish families vaccinate their children, compared to the vast majority of Mennonite families.
Community response and interventions
Local health providers have launched targeted interventions. Union Community Care has administered about 450 measles shots through clinics targeting Plain populations. Due to the outbreak, the organization is offering earlier infant vaccinations than normally scheduled. The crisis has prompted increased vaccine openness among some Amish and Mennonite community members and led to small-scale vaccine clinics being held in Amish communities.
Anne-Marie Derrico, MD, showed the broader risk, stating, "There's no way to imagine that this is going to be an isolated community." Health officials note that Amish leadership has not presented vaccine exemption requests as a religious issue.
Public health context and outlook
Measles, officially eliminated from the U.S. in 2000, can cause serious complications including pneumonia and encephalitis. The current outbreak shows how declining community protection creates conditions for the highly contagious virus to spread. Diego Hijano, MD, MSc, emphasized the interconnected nature of public health, saying, "We are all interconnected."
External influences have played a role. Anti-vaccine activist Robert F. Kennedy Jr. spoke at a Lancaster County fair in 2021, alleging government forced vaccination of the Amish. Health officials now expect measles cases to rise as winter brings more indoor gatherings.
