Herd immunity in some instances, is also called community immunity and is established when there is a sufficient amount of the population who show immunity to the disease thereby preventing spread. There are two ways we can establish immunity. Vaccinations build immunity and provide protection or if you have been sick with the disease, you will build immunity from antibodies.
When many of us were young, including myself, we got a polio vaccine. I had Chicken Pox, Measles, and Mumps which provided me with antibodies to build immunity. My children were lucky enough to receive these vaccines. These are examples of infectious diseases once very common, but now are rare due to the widespread protective vaccination effort which has helped achieve herd immunity in the United States.
Herd immunity, or the point at which enough people in a population have developed antibodies to a disease, is estimated to kick in at about 65 to 70 percent with COVID-19. Other resources reference the herd immunity range at 50 to 90 percent of the population showing antibodies. COVID-19 is still a novel virus, and much is still being learned and unknown . The percentage required is affected by the variants that we are seeing evolve now too. The more infectious the virus mutates, the greater likelihood a higher percentage of the population showing immunity will be required before reaching herd immunity status.
On April 8th, Israeli public health commented that about 56 percent of Israel’s 9.2 million citizens are fully vaccinated against COVID-19 and another 15 percent have recovered from the disease, putting Israel squarely in herd immunity territory, this is first nation to make this claim.
There have been reports about an Amish and Mennonite community in PA reaching herd immunity through infection alone, but this has not been confirmed. Eric Lofgren, an infectious disease epidemiologist at Washington State University said, “It would be the first general population in the United States that’s done it.” Contrasting comments from Alice Yoder, Executive Director of Community Health at Penn Medicine Lancaster General Health, “The only true herd immunity that we can bring as a community is for people to be vaccinated.”
As of April 8, 2021, the US reported 19.4 percent of its’ total population were fully vaccinated with almost 25 percent of adults (18+) being fully vaccinated. Here is a link to the report which is updated regularly COVID-19 Vaccine Tracker: How Many People Have Been Vaccinated In The U.S.? : Shots – Health News : NPR
With access to multiple vaccines which show good efficacy and long-lasting immunity, focus turns to getting as many people vaccinated as quickly as possible. It is difficult to predict the future with so many factors present; new variants, skeptical persons demonstrating fear of vaccine, even isolation fatigue that is almost an epidemic itself. But one thing is certain: The more people who are vaccinated, the less opportunity the virus will have to spread in the population, and the closer we will be to herd immunity.
In the end, we will build up immunity to this virus; life will be able to return to “normal” eventually. The fastest way to get to that point is for each of us to do our part in the coming months to reduce the spread of the virus—continue to wear masks, maintain distance, avoid high-risk indoor gatherings, and get vaccinated as soon as a vaccine becomes available to us.
Resources:
Israel 21C: Israel may have achieved herd immunity against Covid-19. By: Abigail Klein Leichman, April 7, 2021, 2:13pm
Herd Immunity: What Is It and Can It End The Coronavirus Pandemic? (webmd.com)
What is Herd Immunity and How Can We Achieve It With COVID-19? – COVID-19 – Johns Hopkins Bloomberg School of Public Health (jhsph.edu) GYPSYAMBER D’SOUZA AND DAVID DOWDY | UPDATED APRIL 6, 2021
Amish group could reach COVID ‘herd immunity,’: health official (nypost.com)