Millions of kids are behind on routine vaccinations, while those under 12 still can’t get COVID shots: What happens with school, come fall?

The COVID-19 pandemic has caused millions of children around the world to miss routine vaccinations, according to a new scientific report. With children under 12 still ineligible to receive the COVID-19 vaccine, a sizable percentage of younger children will resume school in the fall with vulnerabilities to several illnesses.

The first report, which was published in The Lancet, estimated that 8.5 million more children than expected missed doses of the diphtheria-tetanus-pertussis vaccine, which protects against diphtheria, whooping cough and tetanus, and an additional 8.9 million children missed their first dose of the measles vaccine.

"Although the latest coverage trajectories point towards recovery in some regions, a combination of lagging catch-up immunization services, continued SARS-CoV-2 transmission, and persistent gaps in vaccine coverage before the pandemic still left millions of children under-vaccinated or unvaccinated against preventable diseases at the end of 2020, and these gaps are likely to extend throughout 2021," the researchers wrote. (SARS-CoV-2 is the virus that causes COVID-19.)

The new report coincides with an official bulletin from the Food and Drug Administration saying Thursday that emergency use authorization for COVID-19 vaccines in children under the age of 12 is not likely to happen until early to midwinter.

A study published in the journal Pediatrics earlier this week also found that vaccinations in children "declined markedly" after the pandemic took hold in the United States in 2020. "Among children aged 2 to 18 years, measles-containing vaccine uptake recovered, but total vaccine uptake remained lower," the study states.

It's important to note that most public school districts across the country require that routine childhood vaccinations be completed before a child can attend in-person classes. Some, however, have medical and religious exemptions.

As a whole, the news raises questions about sending younger children back to school in the fall and the risks they may face. However, many parents and doctors agree that children should return to in-person learning in the fall.

"Send them back," one mother of three, Mindy McMillan Saponaro, who works as a school paraprofessional in Maryland, tells Yahoo Life. "My son started back in September for four days a week; my girls shortly after. I have been working in schools since last October, when I got hired full-time, and [am] currently working summer school."

Another mom of three Jen Reynolds Matta, who lives in Delaware, agrees. "At this point during the pandemic, I think we, as a country, need to focus more of our attention to the mental health of students," she tells Yahoo Life. "School is not just about books and learning, it’s about establishing relationships and building friendships, it’s about learning how to work in groups and compromise or share, and it’s about giving students a safe and open environment to communicate their needs and wants. Kids need to be in school."

But doctors say that school may not be back to normal just yet. "The fall for school is going to look like the previous spring — what schools were doing before will likely continue," Dr. Daniel Ganjian, a pediatrician at Providence Saint John’s Health Center in Santa Monica, Calif., tells Yahoo Life.

A father of school-aged children himself, he says that's likely to happen even if the COVID-19 vaccine is authorized sooner than expected, noting that "it would take time" for enough children to get vaccinated to make a noticeable impact.

One infectious disease expert, Amesh A. Adalja, a senior scholar at the Johns Hopkins Center for Health Security, tells Yahoo Life that it's possible for kids to go back to school safely. "We’ve had data from the pre-vaccine era about how in-person schooling can be done safely," he says. "Now it can be done even more safely with some proportion of the population vaccinated."

Adalja says that schools "will have to be mindful of their local conditions, in terms of what the rate of vaccination is, as well as the rate of spread in the community and adjust accordingly." But, he adds, "the default needs to be in-person learning."

Dr. Richard Watkins, an infectious disease physician and professor of internal medicine at the Northeast Ohio Medical University, agrees, telling Yahoo Life that "kids who aren't vaccinated should be wearing masks and trying to socially distance as much as possible."

Dr. Rosemary Olivero, a pediatric infectious disease physician at Helen DeVos Children’s Hospital in Grand Rapids, Mich., who also has school-aged children, tells Yahoo Life that there's still time for parents to get their kids caught up on vaccinations. "For routine childhood immunizations, we need to ensure those required for school entry — measles, mumps, chickenpox, etc. — are fully up to date before the school year starts," she says. "These have fallen to the back of mind for many, with so much emphasis on the novel coronavirus." But, Olivero says, "Routine childhood immunizations are incredibly important for preventing outbreaks of other infectious diseases in classrooms.

"If your child is late in his well-child visits, we strongly recommend scheduling these during the summer months," she says. "Having as much of the eligible population vaccinated against COVID will make classrooms much safer for children and staff, and provide illness spread and room or school closures."

Dr. Jill Weatherhead, assistant professor of infectious disease at the Baylor College of Medicine in Houston, tells Yahoo Life that it's important for parents to do what they can to make sure their kids are as protected as possible. "Parents should verify that their children are up-to-date on routine vaccinations," she says. "If they are not up-to-date, make an appointment with the pediatrician to receive all age-appropriate vaccines prior to school starting. Routine vaccinations are important to not only protect your children from vaccine-preventable illness, but also to keep the community protected through herd immunity.

"If routine vaccination rates in children diminish, we could see the reemergence of previously controlled infections, such as measles," she adds. "This is a particularly dangerous situation for young [children] who are not old enough to get vaccinated, and those children who are not able to get vaccinated or have reduced response to vaccines, like children who have cancer or are on immunosuppressive medications, as these groups of childhood can have very poor outcomes."

While children under 12 can't yet get vaccinated against COVID-19, Weatherhead offers this advice: "Ensure all eligible people in your home and people your children come into contact with have received their COVID vaccination." This, she explains, is called "immunization cocooning" and is done "in order to protect unvaccinated children."

Adalja stresses the importance of in-person learning. "Children have suffered throughout this pandemic, not because of what the virus has done to them, but what adults and teachers unions have done to them," he says. Still, he adds, "It is going to be also critical to keep an eye on other vaccine-preventable diseases, like measles and chickenpox, as vaccination rates have fallen off."

Children may see a more normal school year at some point, Ganjian says — it's just not likely to be in September. "Once we see the numbers going down and more kids vaccinated, then we can get start being more relaxed," he says.

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