There's some encouraging news coming out of Pfizer's Covid-19 vaccine trials for children. The company says its shots "demonstrated 100% efficacy" for kids between the ages of 12 and 15 years old, and it's now hoping to have the vaccine ready for that age group by the fall.

"100% efficacy" may sound too good to be true, but here's how it's analyzed: The company said that in a trial of 2,260 kids, none of those who got the shot ever contracted coronavirus. Of those who got a placebo instead, researchers said 18 later tested positive for the virus.

Interestingly, the company also said that researchers noted a greater antibody response in the 12 to 15-year-olds, "exceeding those reported in trial of vaccinated 16-25 year old participants in an earlier analysis." Pfizer says the vaccines were also "well-tolerated", with side effects similar to those typically reported in adults.

The Pfizer vaccine is the only option so far approved for use in teenagers, with eligibility starting at 16 years old. But armed with this latest data on 12 to 15-year-olds, the company said it plans to ask the FDA for emergency use authorization in "the coming weeks." Its goal would then be "starting to vaccinate this age group before the start of the next school year."

The company is running a separate trial on babies and children from 6 months to 11 years. That trial is broken down by age groups, and Pfizer said the 5 to 11-year-old group has begun receiving doses of the vaccine. The 2 to 5-year-old group will begin receiving doses next week.

Another vaccine maker, Moderna, is also running a vaccine trial for kids between 6 months and 11 years old, though it has not yet released results. Johnson and Johnson also plans to hold trials.

Medical experts see getting kids vaccinated as a key step in ending the pandemic. Dr. Anthony Fauci, the nation's top infectious disease expert, has said that for the U.S. to reach herd immunity—the point when enough people have received the shots that the virus no longer spreads easily—children will have to be included. "We don't really know what that magical point of herd immunity is, but we do know that if we get the overwhelming population vaccinated, we're going to be in good shape. We ultimately would like to get and have to get children into that mix," Fauci said during a Senate hearing this month.

Deciding whether to vaccinate your child isn't necessarily an easy choice for parents, and it's one that should be discussed with your child's doctor. But for those mamas that are hoping that a vaccine for kids will be the beginning of a return to normalcy, this latest data should be encouraging.