(TNS) — California on Tuesday saw some of its highest numbers of new coronavirus cases — surpassing 6,000 new cases in a 24-hour reporting period for the second day straight as the state barreled forward with reopening plans.

Dramatic surges in new cases were seen in various parts of the state: Santa Clara County on Tuesday recorded its highest daily total in new coronavirus cases in more than two months, with 121 cases, a “worrisome” spike, health officials said.

Sacramento County saw its highest count of new cases in a day, at 131. The jump in cases comes as the state reopens restaurants, bars, salons and gyms.

Statewide, more than 190,000 people have tested positive for the virus, with nearly 28 percent of the total cases reported in the last 14 days. John Swartzberg, an infectious disease expert at UC Berkeley, said part of that climb is due to increased testing but that “testing alone is insufficient to account for the increase in the number of cases.”

Multiple sources are driving the surges. Large outbreaks have been reported at several prisons, including San Quentin State Prison in Marin County. Clusters are still coming out of skilled nursing facilities. At least one county has tied local cases to recent civil rights protests.

And as stay-home orders are lifted, more cases are coming from people returning to work and socializing.

California reported a record 6,232 new cases Monday and had surpassed 6,000 cases again Tuesday evening with several counties yet to report, according to data compiled by The Chronicle. Southern California is driving most of the recent spikes, but the Bay Area has seen large increases over the past few days.

The Bay Area had 20,804 cases as of Tuesday evening, and daily reports from the nine counties have regularly passed 300 new cases for the past week. The area set a record Saturday with 619 new cases as Alameda and Contra Costa counties both reported one-day totals above 100.

Cases in Santa Clara County until about a week ago had been mostly stable. But even in a county that has moved slower than anywhere else in the state toward reopening, the outbreak is gaining traction as people return to work and their social lives.

Health officer Dr. Sara Cody said the county anticipated an increase in cases after it began to reopen outdoor activities and parts of its economy. “But recently we’re seeing a worrisome sign that this increase may be accelerating,” Cody told Santa Clara County’s Board of Supervisors on Tuesday.

“This increase reflects both widespread testing - we’re finding more of the cases that do exist - but it also reflects an increase in cases, because the virus continues to spread,” she said.

Cases are climbing at alarming rates in several states, and on Tuesday the governor of Texas in a local television interview advised residents to stay indoors as cases and hospitalization numbers picked up there. Nationally more than 2.3 million people have tested positive and more than 121,000 have died.

The Bay Area had seen mild upticks in cases after slowly easing shelter-in-place restrictions beginning in mid-May, but had mostly avoided some of the larger increases seen in other parts of the state. Over the past week, though, the region has seen notable jumps in cases.

Solano County has reported 33 percent of its overall cases in the last seven days while Sonoma and Napa counties have recorded about 18 percent of their totals in that span.

So far the California surges have not dramatically slowed down plans to reopen the state economy, though a few counties have paused that process when case and hospitalization counts ticked up. Most of the state has reopened vast sectors of the economy, with people now free to return to offices and movie theaters and get their hair and nails done — with some restrictions.

On Monday Gov. Gavin Newsom said he had no immediate plans to reissue stay-home restrictions, but that wasn’t off the table if cases spiked to alarming levels and the outbreak put pressure on hospitals.

Art Reingold, an infections disease expert at UC Berkeley, said Tuesday that the frustrating fact is that it may be near-impossible to drive coronavirus cases down to levels where there’s almost no local transmission.

“It may have been unrealistic to think that these measures were going to have a lasting impact,” Reingold said of shelter-in-place restrictions. “I think some of us, including me — certainly me — underestimated this virus.”

Stephen Shortell, former dean of the UC Berkeley School of Public Health, said even in California, where early and aggressive social distancing measures prevented the outbreak from overwhelming hospitals, case counts may remain stubbornly high for some time.

“I think we can continue to see this trend for the next several months, where there’s going to be ups and downs,” Shortell said. “I’m not surprised to see these increases. Disappointed, but not surprised. This is going to be the new normal until we get a vaccine.”

On Tuesday, the California Department of Public Health changed its description of the state’s testing positivity rate to “trending modestly upward” from “stable” in previous daily updates. According to a Chronicle analysis of state data, California’s seven-day positive rate was 4.89 percent last week, June 15-21, compared to 4.61 percent the previous week and 4.37 percent two weeks earlier.

Hospitalizations, which are not subject to availability of testing, have also been on the rise. California reported 3,868 confirmed COVID-19 hospital patients on Monday - its third consecutive day with a new record total and an 18.8 percent increase over two weeks before. The Bay Area reported 258 confirmed hospitalizations Monday, its highest total since May 30.

People sick enough to need hospital care represent the “tip of the iceberg” for the virus’ impact in a community, Swartzberg said, but: “If hospitals are going up, that can’t be explained by testing alone.”

“We’re not having the disaster that states like Arizona and Alabama and Texas and Florida are having,” Swartzberg said. “We got better after that (initial) surge, we did a really great job at that. But we haven’t really been able to knock these cases down further. They came down and then sort of sat there and just sort of smoldered. But now it looks like maybe it’s going in the wrong direction.”

Santa Clara County, initially the Bay Area’s hardest-hit, until recently had not seen much of an uptick in cases, unlike its neighbors. The county had not reported more than 51 cases on one day since April 11, but over the past six days its daily case counts have shot up.

Cody, the county health officer, said the county has seen fewer cases associated with long-term care facilities since May - after focusing on preventing spread of the virus in that population - but has recorded a jump in cases associated with community and workplace outbreaks.

Cody said 89 worksites in the county have reported at least one positive case in the last month, with construction worksites accounting for 38 percent of that total. Nearly half of the county’s cases since May 1 are of unknown origin and “presumed to be community transmission,” Cody said.

On Monday, Santa Clara County reported its highest number of confirmed hospital patients (48) and intensive care cases (25) since mid-May. Cody said it’s “a bit early” to tell whether the jump in recent cases will translate to more hospitalizations or deaths, but that the county is watching its uptick in hospital numbers “very closely.”

As for Tuesday’s case total, Cody said dates of specimen collection for the positive tests “span many days - but it’s nevertheless worrisome to see so many cases reported to us in one day.”

Swartzberg said more cases were expected as many areas of the state eased shelter-in-place rules and social and economic restrictions but that the recent increase is notable.

“Now is the time to be more cautious, not less cautious,” Swartzberg said. “If anything, just freeze where we are. The best thing we can do perhaps is to take a couple steps back.”

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