- Each child vaccinated against COVID-19 helps reduce the spread of the coronavirus in the community, but will it push the country to herd immunity?
- Reaching herd immunity has often been presented as a pandemic off-ramp, a milestone that will allow us to return to our “normal” lives.
- Vaccinating 5- to 11-year-olds will certainly move the country closer to this tipping point.
More than 900,000 kids ages 5 to 11 have gotten their first dose of a COVID-19 vaccine, the White House said Nov. 10.
As the vaccine rollout for this age group picks up, many are wondering how close this will get the country to herd immunity.
Herd immunity is the point at which enough people are immune to the coronavirus — either through vaccination or prior infection — that any outbreaks that happen would fizzle out.
Reaching herd immunity has often been presented as a pandemic off-ramp, a milestone that would allow us to return to our “normal” lives.
Early on in the pandemic, scientists estimated that at least 70 percent of the population would need protection to reach the herd immunity threshold.
This was based on the original strain of the virus. The more contagious Delta variant has bumped estimates of the threshold to
Vaccinating 5- to 11-year-olds would certainly move the country closer to this tipping point.
“Any progress in building our immunity wall is a welcome one, especially going into the winter months when coronaviruses typically thrive,” said epidemiologist Katelyn Jetelina, PhD, founder of Your Local Epidemiologist.
However, so far, only about 3 in 10 parents of 5- to 11-year-olds are eager to have their child vaccinated, reports the Kaiser Family Foundation.
Children under 18 make up about 23 percent of the U.S. population. Vaccinating as many children as possible is necessary for the country to reach herd immunity.
Especially since children under 5 years old are not yet eligible for the COVID-19 vaccine.
More work is also needed to increase vaccination rates among adolescents and adults — only 69 percent of Americans 12 and older are fully vaccinated, reports the Centers for Disease Control and Prevention.
In addition, vaccination rates are uneven throughout the country, so some communities are closer to herd immunity than others. This could lead to ongoing outbreaks in low vaccination areas.
Even if the United States can increase its vaccination rates, some experts argue that the Delta variant and a waning of the vaccines’ effectiveness against infection have pushed herd immunity further out of reach.
“Thinking that we will be able to achieve some kind of threshold where there will be no more transmission of infections may not be possible,” he said last week to members of the CDC’s vaccine advisory committee.
One reason that reaching herd immunity will be difficult is that the current vaccines don’t entirely block the transmission of the coronavirus.
Although fully vaccinated people are
Likewise, people who’ve had COVID-19 can contract the virus again and pass it on to others.
Individuals with a prior infection were five times more likely to test positive for the coronavirus than fully vaccinated individuals, according to a recent CDC
Another factor affecting herd immunity is the waning protection against infection in the months following vaccination.
Several studies, though, show that vaccines continue to offer
Many experts expect the coronavirus to be with us indefinitely — what’s known as an endemic disease.
The widespread availability of the COVID-19 vaccines, though, will reduce the impact of the virus on the country going forward.
“Even if herd immunity is not achieved for COVID-19 (given the Delta variant), high levels of vaccination will help prevent hospitalizations and deaths as [the coronavirus that causes COVID-19] moves toward endemicity,” Dr. Carlos del Rio, a professor of medicine at Emory University School of Medicine, and his colleagues wrote in
Experts say that vaccinating children can still make a difference, even if the country doesn’t reach herd immunity right away.
“Although kids do not typically get as sick with COVID as adults do, kids can still be hospitalized or have long-lasting effects. So it’s really important for them to get vaccinated in order to protect themselves,” said Dr. Sara Bode, a primary care pediatrician at Nationwide Children’s Hospital and medical director of the hospital’s school-based health and mobile clinics.
Vaccinating children can also reduce the overall community spread of the coronavirus.
Dr. John Bradley, medical director of the Division of Infectious Diseases at Rady Children’s Hospital-San Diego, said data from the CDC and local monitoring of coronavirus cases show that the virus continues to spread among kids 5 to 11 years old.
“Children represent a large ongoing source of active coronavirus infections in communities,” he said. “Once the kids have it, they can spread it to susceptible adults.”
Those at risk include older adults, people with weakened immune systems, and individuals with underlying medical conditions that make them more likely to experience severe COVID-19.
And also the unvaccinated, who make up about one-third of Americans.
Recent data from the CDC shows that unvaccinated people are 11 times more likely to die from COVID-19 than fully vaccinated individuals.
Every person — child or adult — who gets vaccinated reduces the spread of the coronavirus. This, in turn, decreases the chance that a vulnerable individual will be exposed to the virus.
Bradley said that when the American Academy of Pediatrics started recommending the seasonal flu vaccine for children, the number of flu cases among adults dropped, especially among
The effect may be similar with the coronavirus.
“Vaccinating 5- to 11-year-olds is expected to accelerate the decline in cases and ultimately reduce [overall] incidence [of the coronavirus],” said Jetelina, “which is much welcome progress.”
Bradley said vaccinating school-age children may also have a significant impact because they are very active socially — going to parties, playing together in the backyard and on sports teams, hanging out at school.
“To have this group of school kids protected so that they’re not spreading [the coronavirus] in the community is going to be a substantial factor in decreasing community circulation and bringing the pandemic to an end,” said Bradley, a distinguished professor at UC San Diego School of Medicine.
Given that about 7 out of 10 parents of younger children are not ready to have their child vaccinated right away, increasing vaccination rates in this age group will take work.
Part of this is ensuring that all kids have access to the vaccines.
Bode said that might mean having a clinic near where kids live or go to school or ensuring that clinics are held at convenient times for kids and parents.
But it could also mean making sure families have access to good health information and healthcare professionals who can answer their questions.
“Parents have really fantastic questions, so we need to be patient and listen,” said Jetelina. “We need to point them to credible information so they can make evidence-based decisions rather than decisions based in fear.”
Nationwide Children’s Hospital is working with Columbus City Schools to offer information sessions at night where families can ask questions about the vaccines.
It is also offering vaccine clinics inside the schools, so vaccination is easily accessible. If parents can’t attend, children can still get vaccinated with their parents’ consent.
Bode said one of the most critical aspects of outreach is thinking about each community’s needs and trying to meet them where they are.
“When we partner with school personnel that are known and trusted in their community, we can get the word out easily, and we can offer clinics at a time when everyone can come,” she said.
“It sets up a nice opportunity for families to feel comfortable. They’re coming to a place they know.”