Coronavirus updates: 23-year-old college student dies from COVID-19

Most of California will be under a nightly curfew with a new stay-at-home order issued Thursday by Gov. Gavin Newsom, as the state experiences a rapid increase in COVID-19 cases.

Starting Saturday, counties labeled as having widespread risk will be under the order for four weeks. From 10 p.m. to 5 a.m., nonessential activities and gatherings with members outside of the household are banned.

The order currently affects nearly 95% of the state's population.

In a new report ahead of World Children's Day, UNICEF warned the pandemic may create a "lost generation."

Calling the situation "increasingly alarming," UNICEF wrote about the impact on children around the world, including disruptions to health care, nutrition, child protection and education. School closures at their peak have affected 90% of the world's students.

"The impact of the pandemic will affect children’s lives for years to come, even if a breakthrough vaccine becomes available soon," the report said. "How the world responds now to the myriad risks that the pandemic poses to children and adolescents will determine their future. Unless the global community urgently changes priorities, the potential of this generation of young people may well be lost."

UNICEF warned, "Around 2 million additional child deaths under age 5 and 200,000 additional stillbirths could occur over a 12-month period with worst-case interruptions to services and rising malnutrition."

ABC News' Brian Hartman and Kirit Radia contributed to this report.

Louisiana, where the positivity rate has climbed to 7.5%, is in the midst of "the third surge of this pandemic," Gov. John Bel Edwards said.

Including 15 deaths on Thursday, the state's death toll has climbed to 6,199.

Hospitalizations in the state jumped to 929, an increase that's "very concerning," the governor added. "It's increasing at a rate we just can't sustain over time."

Edwards also warned residents to avoid traditional Thanksgiving gatherings.

“If you’re planning on a Thanksgiving that looks like previous Thanksgivings, where you bring extended family, friends around a common dinner table, you’re making a mistake," he said.

ABC News' Rachel Katz contributed to this report.

New Hampshire Gov. Chris Sununu issued a statewide mask mandate that will go into effect Friday.

"In looking at the data, it is clear that a statewide mask mandate is in the best interest of our citizens," Sununu tweeted. "Our hospitalization rate is increasing. We have always said that we cannot let our health care system get overrun, and instituting this mandate will help."

"To those who are opposed to this -- I want to make something very clear: Instituting this mask mandate today will allow us to keep our economy open and helps ensure our health care system has the capacity and workforce it needs in the coming weeks," he continued. "If you don’t wear a mask into a store and are asymptomatically spreading COVID, you risk shutting down that business for weeks, you risk unknowingly infecting someone with severe health issues or someone who works on a longterm care facility."

Everyone over 5 years old must follow the mandate.