The county announced 2,903 new COVID-19 cases, its highest ever reported, and 22 new deaths. Around 1,710 coronavirus patients are hospitalized, Barbara Ferrer, the county’s public health director, said at a news conference.
Of that, 26 percent are being treated in intensive care units and 17 percent are using a ventilator.
Countywide, infections have spiked to more than 100,750 cases and more than 3,320 deaths.
“There’s so much at stake, since these continued increases will result in many more people becoming seriously ill, and many more deaths of COVID-19,” Ferrer said, later warning the dire situation "can be a runaway train if we don't put the brakes on it."
In the weeks after the county began to reopen, the number of new COVID-19 cases held steady, said Dr. Christina Ghaly, the county’s director of health services. However, she said things have taken "a turn for the worse" over the past week.
"We are seeing an increase in transmission. We’re seeing more people get sick and go into the hospital," she said. "This is very much a change in the trajectory of the epidemic over the past several days. It’s a change for the worse and a cause for concern."
More than 1 million country residents have been tested for COVID-19, with the county's positivity rate jumping to 9 percent, Ferrer said.
County health officials last week said around one in every 400 residents had been infected. That number has risen sharply to one in 140 as many people forgo the wearing of face coverings and ignore social distancing guidelines, Ghaly said. Some may not know they're infected, she said.
"The more individuals ignore the guidance on wearing masks and cloth face coverings, physically distancing when possible, exercising discretion on how often, and when and where you go outside of your house, the longer this virus will continue to spread across the county and the more lives will ultimately be put at risk," she said.
Ferrer urged residents to follow safety protocols and to stay at home if possible. She strongly advised against attending gatherings during the July 4 weekend, saying, "This is going to be a different summer."
After the briefing, the county Board of Supervisors announced the closure of beaches, piers, beach bicycle paths and beach access points beginning Friday through July 6.
Ferrer also noted that many restaurants and bars are not adhering to mandated safety measures for operation. Earlier this month, she said as many as 2,000 restaurants were not complying with health guidelines.
"Immediate action is needed," Ferrer said. "All of us, businesses and individuals need to figure out how we personally are going to help to turn things around, otherwise we're quickly moving towards overwhelming our health care system, and seeing even more devastating illness and death."
On Sunday, Democratic Gov. Gavin Newsom ordered bars closed in seven counties -- including Los Angeles County -- for a second time as cases continue to increase. Orange County was added to a watch list of 19 counties that could see a second round of lockdown orders, he said Monday.