(CNN)Health experts say children make up more than 7% of all coronavirus cases in the US -- while comprising about 22% of the country's population -- and the number and rate of child cases have been "steadily increasing" from March to July.
The data was posted alongside updated guidance from the US Centers for Disease Control and Prevention for pediatricians that also includes what is known about the virus in children.
"Recent evidence suggests that children likely have the same or higher viral loads in their nasopharynx compared with adults and that children can spread the virus effectively in households and camp settings," the guidance states.
Transmission of the virus to and among children may have been reduced in spring and early summer due to mitigation measures like stay-at-home orders and school closures, the CDC says.
But now, schools and universities across the country are reopening and in some cases have had to readjust their approach following positive tests among students and staff. How to safely welcome students back has been an ongoing debate between local and state leaders as some push for a return to normalcy and others fear returning to class could prove deadly for some. In some cases, teachers have opted to resign rather than risk contracting the virus.
"So if I'm put into a classroom of 30 or more kids, it's a small room, there's one exit, the ventilation isn't all that great for schools," Arizona teacher Matt Chicci, who quit his job, told CNN. "It's not a good situation."
In Georgia, where several districts reopened in recent weeks, more than 1,000 students and staff were asked to quarantine following cases of coronavirus or exposures to someone infected.
A 15-year-old boy from the Atlanta area became the second-youngest person to die from Covid-19 in the state, according to the Georgia Department of Public Health (GDPH). Earlier this month a 7-year-old boy from Savannah died.
Officials released no further details on how the teen contracted the coronavirus or whether he may have exposed others. But the boy suffered from other health conditions, Nancy Nydam, a spokeswoman with the Georgia Department of Public Health told CNN.
There were 3,372 new coronavirus cases reported on Saturday and 96 deaths, data released by state's health department showed. There has been a total of 235,168 confirmed cases and 4,669 deaths in the state.
North Paulding High School, which came under scrutiny when a student shared a photo of a crowded hallway days after school reopened, reported 12 cases in school and 21 total cases during the week of August 8 to 14. The school switched to full virtual learning this week and will be alternating days on campus starting on Monday.
The "cases in school" refers to the number of people who have tested positive for Covid-19 and who spent some time on a school campus, while the total cases also includes students and staff who tested positive for the virus but were out of school, enrolled in virtual learning or quarantined after being potentially exposed, the Paulding County School District said.
At another public school system north of Atlanta, Courtney Smith decided to transfer her daughters to a charter school after they saw classrooms with 30 to 40 students and few of them wearing masks.
"As parents our number 1 task is to protect our babies and I felt like I was dropping mine off at a death trap," said Smith, whose daughters were enrolled in the Cherokee County School District. "There were a lot of tears shed by me and shed by my children last week."
More than 100 cases have been reported and more than a 1,000 students and employees have been quarantined in the past two weeks, the district said.
'Mini-prom' raises concerns
In Illinois, health officials are looking for people who attended an unofficial "mini-prom." At least five cases were linked to the event and 40 close contacts were identified.
While some US officials -- including the President -- have downplayed the risk coronavirus positions on children, the new CDC guidance notes children can develop severe illness and complications, even if that risk is lower compared to adults. The rate of hospitalizations among children is increasing, the guidance says, and among those hospitalized, one in three children is admitted to intensive care -- the same as adults.
In the US, more than 5.3 million people have been infected with the virus and at least 169,146 have died, according to Johns Hopkins University.
More than 7,000 children have tested positive in Alabama, according to the Alabama Department of Public Health website.
Three pediatric deaths have been reported in Alabama, Dr. Karen Landers, Area Health Officer for ADPH, told CNN in an email. The deaths were two infants and one teenager, all with underlying health problems.
The age group with the highest number of cases is those ages 25 to 49, accounting for 40.24% of all cases in the state, the website shows.
Saturday, New York Gov. Andrew Cuomo said hospitalizations for Covid-19 across the state were at a new low since March 17.
New York was the pandemic's hotbed early on. It now reports 523 people hospitalized for the virus, Cuomo said in a press release.
Meanwhile, the Florida Department of Health reported 6,352 new cases and 204 more deaths on Saturday. This makes 53 straight days of more than 4,000 cases in single day, according to CNN's tally.
Michigan Gov. Gretchen Whitmer signed an executive order to require Covid-19 testing in prisons and jails, according to a press release issued Saturday.
Black and Latino populations hit hard in hotspots
Research published Friday from the CDC also showed that in hotspot counties across the US, Black and Latino people were hit hard by the virus, with a majority of the counties reporting disparities on coronavirus cases in one or more racial or ethnic groups.
"These findings illustrate the disproportionate incidence of Covid-19 among communities of color, as has been shown by other studies, and suggest that a high percentage of cases in hotspot counties are among person of color," said the authors.
In Milwaukee, Wisconsin, health officials say collecting coronavirus impact data by race helped them better strategize a response to the pandemic.
"[It] helped us alter our strategy so we could increase our outreach, add additional testing sites, just really help our communities of color prevent their exposure to Covid-19," said Jeanette Kowalik, commissioner of health at the Milwaukee Health Department.
Kowalik said the data drove conversations that wouldn't have taken place if officials weren't aware more people of color were impacted by the virus.
Doctors warn of lasting heart complications
With new evidence and data on the virus emerging almost weekly, health officials now have another warning: the risk of death from coronavirus-related heart damage seems to be far greater than previously thought, the American Heart Association said.
"Basically this virus can put some patients' bodies on fire, including their hearts," Dr. Dara Kass, an emergency physician at Columbia University Medical School told CNN's Bianna Golodryga on Saturday.
Inflammation of the vascular system and injury to the heart occur in 20% to 30% of hospitalized coronavirus patients and contribute to 40% of deaths, the association said Friday.
Dr. Mitchell Elkind, the association's president, said that the cardiac complications of Covid-19 could be "devastating" and linger after recovery.
The AHA said research indicates coronavirus could lead to heart attacks, acute coronary syndromes, stroke, blood pressure abnormalities, clotting issues, heart muscle inflammation and fatal heartbeat irregularities.
It's a statement that's long been hinted by coronavirus patients across the country, whose bodies were attacked in different ways by the coronavirus.
In Florida, a 21-year-old suffered heart failure while in the hospital and weeks since his recovery, his heart rate is still monitored and he's on medication for his blood pressure -- medications his doctors have said could continue for at least another year.
Kass said people 50 and younger and with healthy immune systems are being affected.
"They're the patients that are surviving this virus, but now they're going to have a new chronic medical condition related to surviving this virus that we need to recognize and treat," Kass said.
Still, Elkind says, there's still a critical need for more research.
"We simply don't have enough information to provide the definitive answers people want and need."