An Amish community in Lancaster County, Pennsylvania may be the first population in the U.S to achieve herd immunity.
Allen Hoover, an administrator of the Parochial Medical Center, which caters to the religious community, estimates that up to 90% of the Amish and Mennonite families in the region have had at least one family member sick with COVID-19.
"So, you would think if COVID was as contagious as they say, it would go through like a tsunami; and it did," said Hoover.
"It was bad here in the spring; one patient right after another," corroborated Pam Cooper, a physician’s assistant at the Parochial Medical Center.
The Plain community, as the religious group calls themselves, originally followed stay-at-home orders and other COVID restrictions at the beginning of the pandemic, canceling school and bi-weekly church services. But by the end of April 2020, the Plain community resumed their normal activities, including the shared communion cup at their worship services and holy kisses (a church greeting among believers). This lead to a widespread outbreak in their community.
In late April and early May 2020, the medical center saw “on average nearly a dozen infections a day, or around 15% of the patients it serves daily.” However, Hoover estimated that fewer than 10% of those presenting COVID symptoms agreed to be tested. This means that the recorded 20% positivity rate (the percentage of positive tests) didn’t accurately reflect the (much higher) number of people infected in reality.
Infections decreased in the summer and surged slightly in the fall. Now, the medical center hasn’t seen a patient with COVID symptoms in the past six weeks, leading to the belief that the Plain community has achieved herd immunity.
Epidemiology experts are less certain.
Epidemiologists from the University of Pittsburgh, Washington State, Johns Hopkins, Emory, and the University of California all agreed that achieving herd immunity, such as in the Plain community, would be rare, but possible.
Eric Lofgren, from Washington State University, said herd immunity to COVID-19 is “extremely unusual” and that the Plain community “would be the first general population in the United States that’s done it.”
Others think vaccination is the only way to really achieve herd immunity. “The only true herd immunity that we can bring as a community is for people to be vaccinated,” said Alice Yoder, executive director of Community Health at Penn Medicine Lancaster General Health.
But the Pennsylvania Amish community believes they have achieved herd immunity, and they see no reason to get vaccinated or follow masking and social distancing mandates.