A federal panel of health experts next week will weigh possible changes in the effort to vaccinate youths against COVID-19 amid rare but concerning reports of heart inflammation in some adolescents, teens and young adults after receiving the shots.

The U.S. Centers for Disease Control and Prevention’s Advisory Committee on Immunization Practices will debate whether young people — who largely face minimal risk from the disease itself — are still better off getting the shots, and if so, whether lowering doses or spacing them farther apart might make them safer.

“It has to be addressed in some way,” said Dr. Monica Gandhi, an infectious disease specialist at the University of California, San Francisco, who is waiting until after the panel discussion to decide whether her 13-year-old son should receive his second shot. “People are worried about it. You don’t want to dismiss something like this.”

The panel’s online meeting had been scheduled for Friday but was rescheduled Thursday to June 23-25 in observance of the newly established Juneteenth National Independence Day holiday.

The CDC has acknowledged “rare” but increased reports of myocarditis and pericarditis mostly in adolescent boys and young men age 16 or older after they received the mRNA vaccines made by Pfizer and Moderna. The inflammation of the heart muscle or lining typically arises within a week, more often after the second of the two shots, with chest pain, shortness of breath and a fast-beating, fluttering or pounding heartbeat.

For now, the CDC continues to recommend COVID-19 vaccination for everyone age 12 years and older, “given the risk of COVID-19 illness and related, possibly severe complications, such as long-term health problems, hospitalization, and even death.”

Other health experts locally agree, though they’re keeping a close eye on the debate.

“No doubt it’s pretty scary, and the good news is it’s quite rare,” said Santa Clara County Health Officer Dr. Sara Cody. “It’s always weighing one benefit over another. I still think far, far and away the benefits of being vaccinated vastly outweigh the risks, even with these cases of myocarditis cropping up.”

The debate comes at a delicate time in the vaccination campaign. Demand for the shots has plateaued to a point where states such as California are offering prizes to entice more people to get vaccinated, yet health regulators also are weighing use of the shots in children under age 12. Currently, 59% of all Californians and 70% of those age 12 and older have received at least one vaccine dose.

Though case rates have plummeted since January, many health experts remain anxious about more dangerous variants of the virus gaining a foothold as California and other states drop pandemic restrictions and mask rules and as schools where kids under age 12 aren’t yet approved for the vaccine prepare to fully open in the fall.

Any hint from federal health officials that they’re worried about the safety of the vaccines, which have only been given emergency use authorization under expedited safety review, would surely make those already reluctant to get the shots more wary.

After the CDC urged a 10-day “pause” in using Johnson and Johnson’s one-shot vaccine following reports of rare blood clots mostly in women under age 50, a May 6 Kaiser Family Foundation survey found just 46% of Americans expressed confidence in its safety, compared with 69% for Pfizer and Moderna.

The CDC has a number of options, Gandhi said. The agency could recommend a “pause” in giving the shots to teens and young adults or allow continued use with a warning of added risks for certain groups, as it did for the Johnson and Johnson vaccine.

The CDC also could advise reducing the vaccine dosage in children, increase the time between shots, limiting youths to just one of the two shots or advising vaccination only in youths with health problems that would make them more vulnerable to COVID-19.

Though there have been no heart inflammation deaths linked to the vaccines, and most cases were reported to have recovered quickly, Gandhi said the incidence appears to be higher than that of the blood clots.

There were 28 reported cases of the blood clots in people receiving the Johnson and Johnson vaccines, 22 of them in women, and three deaths, the CDC reported last month. Per million doses administered, the risk came to 12.4 cases among women ages 30-39; 9.4 cases among women ages 40-49; and 3 cases among older women and men of all ages.

The CDC had received 789 reports of heart inflammation through May. Of those, 475 occurred in people age 30 or younger, and 226 of those were considered confirmed cases. Out of the overall 475 cases, 15 remained hospitalized, three of them in intensive care, and 270 were discharged, 180 of them with full recovery.

Broken down by age group, the preliminary reports of inflammation after the second dose indicated a rate per million doses ranging from 5 cases for those ages 25-39 to as low as 0.9 cases for those 65 and older, all within the range health officials expected.

But the rate per million doses was much higher for younger people — 20.6 for ages 18-24, 35 for ages 16-17, and 22.4 for ages 12-15. The number of cases for those age groups also was two or more times what would be expected, according to the CDC.

At a meeting last week of the U.S. Food and Drug Administration’s vaccine advisory committee, Dr. Tom Shimabukuro, deputy director of the CDC’s Immunization Safety Office, noted more than half of the inflammation reports were in people ages 12-24 who received just 9% of doses administered.

Members of the panel expressed mixed views as they weighed whether to call for longer and broader trials of the vaccines in younger children and whether the small risks in adolescents and teens was justified.

Dr. Paul Offit, a pediatrician at The Children’s Hospital of Philadelphia, noted that despite the low risk to kids today from polio, “we still vaccinate children in this country for polio every year even though we haven’t had a case of polio in this country since the 1970s.”

But others, such as Dr. Cody Meissner, a pediatrics professor at Tufts University School of Medicine in Boston, urged caution.

“The issue for me is at what stage are we going to say we know enough to justify widespread use of the vaccine in adolescents and children,” Meissner said. “The first mandate is to do no harm. We don’t know if we’re doing no harm.”