How Can We Help?
What is herd immunity and why does it matter?
In an interview on June 26th on CNN, Dr. Anthony Fauci acknowledged we don’t yet know what the efficacy of a COVID-19 vaccine will be, but that he would “settle” for 70 to 75% effective. Why that number? If 70 to 75% of the population is immune to COVID, we would achieve “herd immunity” to quell the outbreak.
Herd immunity is when a sufficient proportion of the population is immune to an infectious disease, either by vaccination or prior infection, so that spread from person to person is unlikely. A population with 75% immunity to COVID-19, therefore, would mean that 3 of every 4 people exposed to the virus won’t get sick (and won’t spread the virus any further). Achieving that level of immunity allows a level of safety for others, who because of age, having a weakened immune system or other medical considerations, cannot be safely or effectively vaccinated.
The challenge, however, is not just to manufacture and distribute enough vaccine to 75% of a population, but for 75% of people to agree to be vaccinated. A CNN poll in May found that one-third of Americans said they would not try to get vaccinated against COVID, even if the vaccine is widely available and low cost. Asked if a vaccine with 70-75% efficacy taken by only two-thirds of the population would provide herd immunity, Dr. Fauci answered “No — unlikely.”
Fauci noted that “there is a general anti-science, anti-authority, anti-vaccine feeling among some people in this country — an alarmingly large percentage of people, relatively speaking.” Given the power or the anti-vaccine movement, “we have a lot of work to do” to educate people on the truth about vaccines.
Sky Pittson, MD, June 29, 2020