Protests against mandated COVID-19 vaccines pop up across US

Former President Barack Obama has decided to "significantly scale back" his 60th birthday party on Martha’s Vineyard due to the spread of the delta variant, according to a spokesperson. Hundreds of guests were expected to attend.

"This outdoor event was planned months ago in accordance with all public health guidelines and with covid safeguards in place. Due to the new spread of the delta variant over the past week, the President and Mrs. Obama have decided to significantly scale back the event to include only family and close friends," spokesperson Hannah Hankins said in a statement.

Obama’s office did not give a new estimate of how many guests will attend.

-ABC News’ Sarah Kolinovsky

President Joe Biden is calling out Florida Gov. Ron DeSantis and Texas Gov. Greg Abbott for rejecting mask mandates in their states.

"I believe the results of their decisions are not good for their constituents," Biden said of the governors at a Tuesday news conference.

Biden said Florida and Texas are accounting for one-third of the new COVID-19 cases in the country.

"We need leadership from everyone. If some governors aren't willing to do the right thing to beat this pandemic, then they should allow businesses and universities who want to do the right thing to be able to do it," Biden said. "I say to these governors, 'Please help. But if you aren't going to help, at least get out of the way.'"

Nearly 72,000 children in the U.S. tested positive for COVID-19 last week, a massive jump from the approximately 39,000 cases among kids one week earlier, according to a new report from the American Academy of Pediatrics and the Children’s Hospital Association.

Children represented 19% of all COVID-19 cases for the week ending July 29.

Severe illness due to COVID-19 remains "uncommon" among children, the two organizations wrote in the report. According to the nearly two dozen states that reported pediatric hospitalizations, 0.1% to 1.9% of all child COVID-19 cases resulted in hospitalization.

However, the two organizations warned that there is an urgent need to collect more data on long-term impacts of the pandemic on children, "including ways the virus may harm the long-term physical health of infected children, as well as its emotional and mental health effects."

-ABC News’ Arielle Mitropoulos

According to federal data, nearly 56,000 patients are now hospitalized with COVID-19 across the U.S., marking the highest number of patients receiving care since February.

Ninety-one percent of Americans are now living in high (a seven-day new case rate ≥100) or substantial (a seven-day new case rate between 50-99.99) community transmission in the last week.

Seven states -- Alabama, Arkansas, Arizona, Delaware, Florida, Louisiana and South Carolina -- have high or substantial community transmission in every county.

Louisiana, Arkansas, Florida, Missouri, and Alabama currently have the nation's highest case rates, followed by Mississippi, Texas, and Oklahoma.

-ABC News’ Arielle Mitropoulos