Leng Vong Reiff had just received her second dose of a Covid vaccine and thought guiltily of her two young, unvaccinated sons. So she began banging away at her keyboard.
Like countless parents across the nation, she was searching for vaccine clinical trials for children. She managed to find one, applied and got a call back.
“They said that a clinic in Nebraska had an opening right now, four hours away,” she recalled. Better yet, this was a placebo-free trial, so she knew her sons would be given the bona fide vaccine.
A resident of Clive, Iowa, Ms. Vong Reiff bundled Logan, 9, and Quentin, 5, into her car and raced west on Interstate 80 to the clinic, where her sons received their first shots of the Pfizer-BioNTech vaccine. They returned three weeks later for their second shots, protecting them for the school year ahead. And they will go back in December for antibody testing.
Families are confronting difficult situations, now that most schools have reopened after as many as 13 months of remote teaching. As the highly contagious Delta variant has taken hold, dozens of schools around the country have closed classrooms or paused sessions, especially in states with low vaccination rates.
Forty-eight million children in the United States are under 12 and not eligible yet for a vaccine endorsed by the Food and Drug Administration.
And about 252,000 children, including teenagers, tested positive in early September, the largest number of such cases since the start of the pandemic, according to an American Academy of Pediatrics analysis.
Of those 12 through 17 who are eligible to get a Covid shot, roughly 54 percent have received at least one dose. But public health experts say it will be months before the F.D.A. decides whether the results of various clinical trials for those who are 5 to 11 and 2 to 5 merit authorizing the shots for the youngest age groups.
With few options other than taking precautions like mask-wearing, some parents have even sought, through their pediatricians, off-label shots that are adult doses, a practice the F.D.A. discouraged on Friday. The agency warned that “children are not small adults,” and that the adult doses now in wide use have not been fully studied for potential safety risks in younger children.
There’s no question that this summer has been particularly trying for parents, especially after public health experts warned that the Delta variant was highly transmissible — even from vaccinated household members. Although children still are less likely than adults, especially older adults, to be hospitalized or die from Covid, nearly 30,000 children were admitted to hospitals with Covid in August, the highest levels to date during the pandemic.
The hospitalization rate in mid-August for children and adolescents with confirmed Covid was nearly five times the rate in late June, according to a study released earlier this month by the Centers for Disease Control and Prevention. That rate climbed nearly tenfold among children newborn to 4 years old, the report found.
Covid-related emergency room visits and hospital admissions also increased among children in mid-August, according to a second C.D.C. study.
Geography played a role, the researchers found. Those visits and admissions occurred 3.4 and 3.7 times more in the states with lower vaccination rates.
Parental anxiety has fueled the demand for slots in children’s vaccine trials and made appointments scarce. Pfizer, for instance, is fully booked in its clinical trial, a spokeswoman said.
So Ms. Vong Reiff most likely nabbed a cancellation slot in Nebraska.
Dr. Tina Sosa, a mother of two, did not have to travel far to get her son vaccinated in a trial. A pediatric hospitalist, Dr. Sosa was on a fellowship at Cincinnati Children’s Hospital Medical Center when Pfizer began a trial there.
Her older son, Brandon, 3, had no side effects from the two shots he received in April, she said. “I even squeezed his arm and asked did it hurt, and he said no.”
Dr. Sosa has since moved to Rochester, N.Y., where she works at the University of Rochester Medical Center. Her 7-month-old son, Leo, is to begin a Moderna trial next month, while Brandon will follow up on his trial in Cincinnati via an app and telephone, Dr. Sosa said.
In his push for vaccine mandates on Thursday, President Biden expressed the need to develop vaccines to protect children younger than 12.
“Now if you’re a parent of a young child and you’re wondering when will it be, when will it be — the vaccine — available for them, I strongly support independent scientific review for vaccine uses for children under 12,” he said. “We can’t take shortcuts of that scientific work.”
The three major U.S. drug companies making vaccines are at different stages when it comes to children’s trials.
Pfizer is now conducting a single trial for children under 12, Kit Longley, a spokeswoman, said.
The trial has included 4,500 children in its first phase: 3,000 who are 5 to 11; 750 who are 2 to 5; and 750 who are 6 months to 2 years. Its second and third phases include 4,500 children.
The company anticipates having its trial data for children ages 5 to 11 later this month, and after more review, potentially will request F.D.A. emergency use authorization for that age group, Ms. Longley said Friday.
Moderna announced on Thursday that the company had finished its enrollment of children ages 6 to 11, totaling 4,000 children, for its trial. The company said it expected to file for F.D.A. emergency-use authorization for that age group by the end of this year.
Another application should be filed in early 2022, the company said, based on the results of a trial for children 5 and younger. In all, Moderna expected to enroll about 12,000 children, Colleen Hussey, a company spokeswoman, said.
Johnson & Johnson has started its Phase 3 clinical trial in adolescents from 12 to 17, and will submit the findings to regulators when finished, according to a company spokesman, Jake Sargent.
The company is also planning several other studies, he said. One will include children from 6 to 11, followed by children 2 to 5. Another will look at those younger than 2.
Impatient parents who are seeking off-label adult shots for their children concern officials like Dr. Sean O’Leary, vice chairman of the committee on infectious diseases at the American Academy of Pediatrics.
“It’s a bit of the Wild West out there,” said Dr. O’Leary, a professor of pediatrics at the University of Colorado Anschutz Medical Campus and Children’s Hospital Colorado.
Understand Vaccine and Mask Mandates in the U.S.
- Vaccine rules. On Aug. 23, the Food and Drug Administration granted full approval to Pfizer-BioNTech’s coronavirus vaccine for people 16 and up, paving the way for an increase in mandates in both the public and private sectors. Private companies have been increasingly mandating vaccines for employees. Such mandates are legally allowed and have been upheld in court challenges.
- Mask rules. The Centers for Disease Control and Prevention in July recommended that all Americans, regardless of vaccination status, wear masks in indoor public places within areas experiencing outbreaks, a reversal of the guidance it offered in May. See where the C.D.C. guidance would apply, and where states have instituted their own mask policies. The battle over masks has become contentious in some states, with some local leaders defying state bans.
- College and universities. More than 400 colleges and universities are requiring students to be vaccinated against Covid-19. Almost all are in states that voted for President Biden.
- Schools. Both California and New York City have introduced vaccine mandates for education staff. A survey released in August found that many American parents of school-age children are opposed to mandated vaccines for students, but were more supportive of mask mandates for students, teachers and staff members who do not have their shots.
- Hospitals and medical centers. Many hospitals and major health systems are requiring employees to get a Covid-19 vaccine, citing rising caseloads fueled by the Delta variant and stubbornly low vaccination rates in their communities, even within their work force.
- New York City. Proof of vaccination is required of workers and customers for indoor dining, gyms, performances and other indoor situations, although enforcement does not begin until Sept. 13. Teachers and other education workers in the city’s vast school system will need to have at least one vaccine dose by Sept. 27, without the option of weekly testing. City hospital workers must also get a vaccine or be subjected to weekly testing. Similar rules are in place for New York State employees.
- At the federal level. The Pentagon announced that it would seek to make coronavirus vaccinations mandatory for the country’s 1.3 million active-duty troops “no later” than the middle of September. President Biden announced that all civilian federal employees would have to be vaccinated against the coronavirus or submit to regular testing, social distancing, mask requirements and restrictions on most travel.
Jennifer Macklom of Cedar Park, Texas, was determined to get her three daughters enrolled in a trial. Haunting her were the memories of 2016, when her daughter Miriam had grown sick with an adenovirus at age 2 ½. Simultaneously, her daughter Naomi, who was only 6 weeks old at the time, contracted a form of the coronavirus that pre-dated Covid.
Miriam was taken by ambulance to the Dell Children’s Medical Center in Austin. Naomi was admitted through its emergency room.
Both girls were hooked up on oxygen and feeding tubes at the same time, Ms. Macklom recalled.
“I said, ‘I can’t do that again. I can’t emotionally have anyone I love or even know be hooked up to one of these things,’” said Ms. Macklom, a high school mathematics teacher.
So, with the advent of the pandemic, she conferred with her pediatrician, and all three children landed on a waiting list for a vaccine trial. Miriam is now 8, Naomi, 5, and Ruth, 2.
Five months passed. Then the phone rang, and Ms. Macklom learned that her daughters were at the top of the list to receive the Pfizer vaccine at a branch of Austin Regional Clinic, in central Texas.
So many parents were interested in that trial for the under-12 age group that the staff had no need to recruit them, according to Heidi Shalev, a clinic spokeswoman.
Ruth was too young for vaccinations at that site. Now, to avoid the risk of contracting the virus at day care, she is spending weekdays with Ms. Macklom’s parents.
Miriam and Naomi got their two shots. They don’t know if they contained the vaccine, since this trial called for one-third of shots to be a placebo. The children had to wait for an hour after the injections, and the staff gave them a coloring book and rice crispy treats.
The girls will learn in early winter if they got the vaccine or the placebo. If it is the placebo, they will receive shots of the real stuff.
“Getting in the study was so life-changing,” Ms. Macklom said. “We actually went out camping.”
Ms. Vong Reiff, who owns her own marketing firm, also decided to enroll her sons in the trial to protect her husband, who underwent surgery and radiation for nonmalignant meningioma, she said.
In mid-August, the entire family headed to Maine, to Bar Harbor and Acadia National Park, and then to Boston for a duck boat tour.
“Had the boys not been vaccinated, we wouldn’t have gone,” Ms. Vong Reiff said. “For us, it was a kind of celebration to be vaccinated, slowly getting back to who we were.”