CNN  — 

After a week of skyrocketing coronavirus cases in the United States, officials are issuing a stark warning this July Fourth: Skip the parties.

If you really have to go, wear a mask, wash your hands and maintain social distancing. And if you must host, try to keep festivities outdoors and save the partygoers’ information for future contact tracing if needed.

Coronavirus cases have been rising in 36 states with California, Arizona, Texas and Florida all posting record numbers of new infections this week.

The Florida Department of Health reported 11,445 new cases of Covid-19 on Saturday – yet another record for new coronavirus cases reported in a single day. The previous record was set on Thursday, with 10,109 cases.

Nationwide, the virus has killed more than 129,000 people and infected over 2.8 million since the pandemic started, according to Johns Hopkins University. And for the third straight day Friday, the number of new cases surpassed 50,000 nationwide.

Despite the bleak milestones, President Donald Trump said Saturday that 99% of coronavirus cases “are totally harmless” and the rising number of cases are caused by increased testing.

“Now we have tested, almost 40 million people. By so doing, we show cases – 99% of which are totally harmless — results that no other country can show because no other country has testing that we have. Not in terms of the numbers, or in terms of the quality,” Trump said during remarks on the White House South Lawn.

Of the 36 states whose new cases have gone up this week compared to the previous one, nine of them have increased by over 50%. They are Montana, Idaho, Nevada, Florida, Georgia, Tennessee, Louisiana, Alaska and Delaware.

People yearning for some normalcy hosted barbecues, found crowds in Virginia Beach, Virginia, and attended gatherings to watch fireworks. Meanwhile, others were finding beaches in Miami and Los Angeles closed, tubing in Texas rivers banned and some city celebrations happening mostly on livestreams.

Fireworks light up the sky on June 30 in New York City, part of July Fourth displays in locations around the city that are kept secret to minimize crowds gathering due to the coronavirus pandemic.

Without stringent safety measures, health experts fear the holiday weekend could bring a wave of new infections that could overwhelm hospitals. To avoid a public health disaster, they’re imploring people to wear masks, skip bars and crowded places, and avoid mixing with people outside of their households.

“What we know is that our behavior is the most powerful tool we have right now against the virus,” said Dr. Nadine Burke Harris, surgeon general of California. “And we really need folks to, you know, step up. I know that folks are tired, but it’s absolutely critically important.”

Some beaches open for revelers, others stay closed

Beaches in Huntington Beach, California, would typically be packed with beachgoers this weekend. Just two weeks ago on June 14, photos showed the beach packed with people, towels and umbrellas.

But on Saturday, beaches in the Los Angeles area are closed due to rising Covid-19 cases, and beaches were left empty with large stretches of untouched white sand.

A normally crowded beach in Huntington Beach, California, is empty on July 4, 2020.

Renee Van Arsdale, who was riding bikes with her husband near the beach, told CNN there would usually be a “sea of people” on the beach for July Fourth.

“But today it’s mostly locals just enjoying the beauty of the beach instead of being on the beach,” she said.

Her husband, Gary Van Arsdale, pointed out that the city of Huntington Beach had to cancel its annual July Fourth parade. Instead, the city put on a neighborhood tour with small-vehicle caravans that weaved through the streets with local dignitaries.

Revelers enjoy the beach at Coney Island in the Brooklyn borough of New York on Saturday, July 4, 2020.

Beaches were open elsewhere, like New York’s Coney Island. There were also beachgoers at Clearwater Beach in Florida, though there were fewer than typical for the holiday weekend.

At Clearwater, some had gathered in groups, according to a CNN crew on the scene, despite signs on the beach that warned not to gather in groups of 10 or more. But many at the beach told CNN they were taking certain precautions like wearing masks and having hand sanitizer at the ready.

Local resident Connor Gourley — who believed he had the coronavirus earlier in the year and recovered — told CNN he wasn’t “necessarily concerned” about being on the beach. He wasn’t going to let concerns about the virus stop him from celebrating Independence Day, he said.

“It’s not more about the partying, it’s about celebrating America and our Independence Day,” he said. “So, no matter what we’re going to be out here and we’re going to be American and enjoy our freedom.”

A view of an empty South Beach in Miami Beach, Florida, on July 4, 2020.

Some officials have made small exceptions for July Fourth festivities, so long as people adhere to restrictions. In Harris County, Texas, Judge Lina Hidalgo issued a countywide order prohibiting outdoor gatherings of 10 or more except for a handful of activities, including fireworks.

The order, signed Friday, says fireworks displays and gatherings with more than 100 people are allowed only if people view the celebrations from inside a vehicle. The order will remain in effect through at least Wednesday, August 26. It also includes exceptions for gatherings of 10 or more people at religious services, youth camps, swimming pools and certain sporting events.

“I think this is the real challenge we have,” Dr. Umair Shah, executive director of Harris County Public Health, told CNN Saturday. “It’s 4th of July now. All of us should be coming together as Americans to fight this pandemic. It is not just going to go away.”

Health care workers make plea to governor

In Georgia, where coronavirus cases are going up, about 1,400 health care workers signed a letter to Gov. Brian Kemp asking him to increase state restrictions to slow the spread of the coronavirus.

The letter dated Thursday urged the governor to close bars and nightclubs and prohibit indoor gatherings of more than 25 people, including at places of worship. It also recommends a statewide face covering requirement that allows mayors and county officials to institute requirements appropriate for their jurisdictions.

“During the past week we have seen a sharp spike in cases that cannot be accounted for by increased testing. We also are seeing a very troubling increase in hospitalizations that, if continuing, will overwhelm our healthcare infrastructure, not only in metro Atlanta but also in rural Georgia,” the letter said.

Dr. Jesse Couk, the chair of infectious disease at Shepherd Center and a doctor at Piedmont Atlanta Hospital, told CNN he worked with other doctors and health care professionals to create the letter after he became frustrated with lack of action after a spike in cases.

Couk and other medical contacts worked together to create the letter and have other health care professionals sign it. He said he wanted to highlight the need for increased social distancing and further restrictions to slow the spread and was speaking as a member of the Infectious Disease Society of Georgia and not as a representative of Piedmont Atlanta.

Health care workers push a patient from the Covid-19 unit at United Memorial Medical Center in Houston.

More states make sweeping mask mandates

Mask mandates for Texas and Kansas went into effect Friday, which means 19 states and Washington, DC, now have such requirements.

“We have the ability to keep businesses open and move our economy forward so that Texans can continue to earn a paycheck, but it requires each of us to do our part … and that means wearing a face covering in public spaces,” Texas Gov. Greg Abbott said.

Other governors have also issued statewide orders, including California, Connecticut, Delaware, Hawaii, Illinois and Michigan. And in Tennessee, Gov. Bill Lee signed an executive order granting mayors in 89 counties the authority to issue mask requirements. It allows local governments to issue the mandates if a surge requires more preventative measures.

“While our densely populated urban areas continue to have the highest Covid-19 case rates, our local governments expressed a need for greater flexibility in addressing a rise in cases and that includes setting stronger expectations around masks,” Lee said in a statement. “This targeted approach ensures we protect both lives and livelihoods and safely keep our economy open in Tennessee.”

In Myrtle Beach, South Carolina, the beaches will be open to thousands of visitors for the holiday weekend — but with a mask requirement to help stop the spread, Mayor Brenda Bethune said.

US commercial labs report testing delays

Rising demand for Covid-19 testing has led some major commercial laboratories to report delays in turning around test results.

Testing demands have reached “unprecedented levels,” commercial laboratory Quest Diagnostics said this week, leading to delays in notifying clients of their results.

Although Quest can provide results within a day for priority patients — including sick health care workers and people in the hospital — the average turnaround time is three to five days for most other patients, the company said in a statement Monday.

While the number of tests conducted across the US is increasing, experts say long turnaround times can make it difficult to isolate confirmed cases and quickly quarantine their close contacts.

Another commercial laboratory, LabCorp, is reporting delays. The company told CNN in a statement Saturday that reporting test results may take one to two days longer now, leading to a current turnaround time of two to four days on average.

“In recent weeks, we have seen a steady increase in demand for molecular testing and we are doing everything we can to continue delivering results in a timely manner while continually increasing testing capacity,” LabCorp said.

CNN’s Jeremy Diamond, Kevin Bohn, Steve Almasy, Arman Azad, Nicole Chavez and Ray Sanchez contributed to this report.