When will life return to normal?
It’s a question that’s at the front of everyone’s minds. Now that we’re in the first phase of vaccination—an unprecedented feat—we can at least start to imagine an eventual return to the way things were in the Before Times. Exactly when that point will arrive hinges on the answer to a second question: How many people need to be vaccinated in order to stop COVID-19?
Pedro Mendes, a computational biologist at the University of Connecticut, believes he has that answer. Using a computer model, Mendes estimates that “roughly 70% of the [American] population needs to be vaccinated to stop the pandemic.”
But there are some variables that could affect that number, Mendes writes. Chief among them, whether the various vaccines available to us now prevent infection entirely or just prevent people from getting sick.
Why the vaccines are critical
The clinical trials have shown that both the Pfizer-BioNTech and Moderna vaccines, the two currently authorized by the FDA for emergency use in the United States, are remarkably effective at preventing people from getting sick with COVID-19. But a person who doesn’t get sick can still be infected with the coronavirus.
Why does that matter? Because researchers haven’t yet been able to determine whether a vaccinated person can or cannot spread the virus to others. Let’s hope for the best and assume that they can’t.
In that case, “when enough of the population is vaccinated, the virus has a hard time finding new people to infect, and the epidemic starts dying out,” Mendes says. “And not everyone needs to be vaccinated. Just enough people to stop the virus from spreading out of control.”
You may have heard of herd immunity. The scenario that Mendes describes is herd immunity: Once a certain amount of people in a population are vaccinated, the virus essentially can’t find anyone else to infect.
A big question remains unanswered
There’s another important consideration, Mendes writes. His computer model assumes that people interact randomly. In reality, he says, we move in “highly structured networks depending on work, travel, and social connections.”
That difference is important because it means that the percent of the population that needs to be vaccinated to create herd immunity is “considerably smaller” than the 70% forecast by Mendes’s computer model.
Ultimately, herd immunity will depend on whether the vaccinations can prevent the transmission of COVID-19. “If vaccinated people can still be infected and pass on the virus, then vaccination will not provide herd immunity,” Mendes says.
It will, however, prevent serious illness, and that will be enough, for the time being, to allow us to begin picking up the pieces and planning for brighter days.
How you can help us
For the last 55 years, NORWESCAP has been helping to support low-income families and individuals across Northwest New Jersey. Today, as our region and country face the threat from COVID-19, that commitment is stronger than ever.
If you’re looking for opportunities to volunteer, donate materials, or otherwise support NORWESCAP’s work during this crisis, call MaryBeth Ringo at 848-459-5882 or email her at firstname.lastname@example.org. Monetary donations may be made here.