Contra Costa County reported 92 new COVID-19 cases on Saturday, the most ever reported in a single day in the county. That comes on a day where at least four Bay Area counties reported no new fatalities from the virus.

Contra Costa County’s 92 new COVID-19 cases bring its total to 2,240 cases. The second-highest single day case total in the county was on June 9, when the county reported 68 new cases. On Friday, the county also reported the most tests ever — 2,448, after reporting 2,016 new tests on June 19. The number of positive tests ticked up slightly to 3.2 percent. It’s not clear how many of the tests reported on Friday were positive.

Contra Costa County has also had 56 deaths from COVID-19 since the start of the pandemic.

Alameda County, which since May 18 has had the most coronavirus cases in the Bay Area, reported 103 new cases on Saturday, the third day with more than 100 daily cases since June 16. The county has reported 4,805 total cases and 118 deaths. There were no new fatalities reported on Saturday.

The seven-day rolling average of new tests conducted in Alameda County declined from a peak of 2,552 on Tuesday, to 1,994 on Friday, the most recent data available. The seven-day average positivity rate for tests in the county dropped slightly on Friday to 3.4 percent.

The rising case totals in East Bay counties are in sharp contrast with San Francisco, which only reported one new case and no fatalities on Saturday. The county has had 3,058 cases and 47 deaths from the virus. The county entered Saturday with a seven-day average of 25.6 new cases and 0.43 deaths.

On Wednesday, the most recent day available, the county reported 1,935 new tests with a positive rate of 2 percent.

Santa Clara County reported 60 new cases and no new deaths for a total of 3,458 cases and 152 fatalities. The county entered Saturday averaging 40 new cases and 0.29 deaths and has only reported two new fatalities since Sunday, June 14. Only one of the 783 people whose test results were released on Friday was positive for COVID-19, and the county has an overall positivity rate of 2.9 percent.