A company announcement Thursday that a small clinical trial showed that a booster shot of Pfizer’s BioNTech coronavirus vaccine boosted the immune responses of 140 children ages 5 to 11 comes as new U.S. virus cases surge again.
The rebound was particularly noticeable in the Northeast, where the Omicron subvariant known as BA.2, now the dominant version of the virus in the United States, first took hold.
dr Anthony S. Fauci, President Biden’s senior medical adviser, has warned in recent days that the United States could see a significant spike in infections over the next few weeks. However, he said hospitalization rates are unlikely to increase at the same time because so many Americans have some level of immunity, either from vaccines or previous infections.
Several hundred children aged 5 to 11 have died from Covid since the pandemic began, according to the Centers for Disease Control and Prevention, but pediatric immunizations have been a hard sell for many parents. Only about 28 percent of children in this age group have received two doses and would be eligible for a booster shot. About 7 percent received only one dose, according to the agency.
There was an initial rush for vaccinations after they were first offered to this age group in November, but the rise in vaccination rates then slowed to a crawl. Last month, for example, it rose by a single percentage point.
dr Kathryn M. Edwards, a pediatric vaccines expert at Vanderbilt University School of Medicine, said some parents feel the chances of their children getting seriously ill are slim while the vaccines are unknown. She said some research suggests 45 percent of children who become infected have no symptoms.
“The problem is that we can’t predict who will get sick and who won’t,” she said. And among those who do, she said, “there will be children who will be hospitalized and there will be a few deaths.”
dr Sally Goza, a Fayetteville, Ga., pediatrician and former president of the American Academy of Pediatrics, said some parents see no reason to act because they view the pandemic as suppressed. “I’ve had parents come into my office and say, ‘Covid is over. I don’t have to worry about that,” she said.
To a degree, she said, parents have also been stunned by wave after wave of infection. “People are tired of dealing with it. They just say, ‘We’re just going to take our chances,'” she said.
According to a study by the Kaiser Family Foundation, the proportion of children aged 5 to 11 who take at least one dose varies greatly from region to region. Five of the top 10 states with the highest rates were in New England, while eight of the 10 states with the lowest rates were in the South.
Although more than 250 million Americans have been safely vaccinated since the pandemic began, many parents fear unknown consequences for their children. Compared to vaccinations to protect against measles, mumps and other diseases that have been around for decades, the Covid vaccines are brand new.
A study by New York researchers, posted online in late February, found that the effectiveness of Pfizer’s vaccine against infection in children ages 5 to 11 increased from 68 percent to 12 percent within 28 to 34 days after the second dose fell off.
That was a steeper decline than in older adolescents and teenagers who received a much higher dose. Some experts suggested that the difference in dosage explained the protection gap, while others blamed the Omicron variant, which was prevalent during the study.
Another CDC study found that two doses of Pfizer reduced the risk of Omicron infection by 31 percent in 5- to 11-year-olds, compared to a 59 percent reduction in risk in 12- to 15-year-olds.
Pfizer’s vaccine is so far the only one approved for people under the age of 18.