Herd immunity unlikely without vaccinating kids
Johns Hopkins expert says 75-85% of population need to be immune
The United States is unlikely to reach much-needed herd immunity against the coronavirus unless children can be vaccinated too, according to a Johns Hopkins University public health expert.
Herd immunity, a form of indirect protection from viruses when a large portion of the population is immune, is directly connected with vaccination rates, said Colleen Barry, chairwoman of the department of health policy and management at Johns Hopkins.
Barry said about 75 to 85% of the population would need to be immune to the coronavirus to reach the desired threshold for herd immunity.
But children make up about 22% of the United States population according to census data, and vaccines have not yet been approved for kids under 16 years old.
“It’s unlikely that we’ll have a level of immunity in the population that halts transmission in our communities without an authorized vaccine for those under 16 years of age,” Barry said in a Thursday virtual briefing.
Pharmaceutical companies are working quickly to solve this problem. Just this month, Pfizer dosed the first healthy children in a global study to further evaluate the safety of its coronavirus vaccine in kids 6 months to 11 years old.
Moderna is working on a similar study, and announced last week the first participants had been dosed in a study of its mRNA vaccine in children aged 6 months to less than 12 years.
Dr. Anthony Fauci, the nation’s top infectious disease doctor, told lawmakers last week that high school kids will likely be able to be vaccinated in the fall of 2022.
Several other factors could stand in the way of achieving herd immunity, though. Barry said vaccine hesitancy, misinformation and coronavirus variants all threaten pandemic progress that could get us back to normal.
However, case rates in the United States have plateaued in recent weeks at around 50,000 new cases per day, Keri Althoff, epidemiology professor at Johns Hopkins noted. Taking a question from the Herald, Althoff said regaining some normalcy can happen when that numbers start to tip down.
“That will signal to us that the community level immunity protection has ballooned up to a safer place,” Althoff said.
Barry added that the plateau suggests a need to dial up public health measures so hospitalizations can decline.
More than 133 million vaccine doses have been administered in the United States so far, according to Centers for Disease Control and Prevention data, and with more supply on the way, better days are on the horizon.