Bay Area coronavirus cases more than double in 1 month, data shows

SAN FRANCISCO (KGO) -- California has experienced a surge in coronavirus cases, and the Bay Area is no exception. ABC7 News' data journalism team looked at the numbers and found that for most counties, and the Bay Area overall, cases are increasing at a continually faster pace.

For cumulative cases encompassing the greater ten Bay Area counties, it took four months for the area to reach 30,000 positive cases, which occurred on July 7. However, it only took one month for cases to double to 60,000, which the area reached on Aug. 7.

WATCH LIST: 42 California counties where COVID-19 is getting worse

Similarly, it took 60 days from when ABC7 started recording local cases on March 12 for the Bay Area to reach 10,000 cases, which occurred on May 11. In mid-August, it only took seven days for the area to jump from 60,000 to 70,000 cumulative positive cases on Aug. 14.


App users: For a better experience, click here to view the graph in a new window.

The Bay Area reported 33,123 cases on July 12. (Since ABC7 News started recording cases on March 12, we decided to look at monthly cases using that date for each month.) By Aug. 12, that number had jumped to 66,861, doubling the number in a matter of weeks.

When looking at each county individually, many of them show similar rates. On July 12, Santa Clara had over 5,000 reported COVID-19 cases in the county. On Aug. 12, that number had reached nearly 13,000, more than doubling over the course of a month.

Contra Costa had 4,000 cases on July 12 and over 9,000 cases a month later, also more than doubling.

INTERACTIVE: Here's the reopening status of every Bay Area county

Hover over the chart below to see each Bay Area county's COVID-19 cumulative case count from month to month.


App users: For a better experience, click here to view the graph in a new window.

Marin County experienced a large bump in cases starting in late June due to a COVID-19 outbreak at San Quentin State Prison, which is located in the county. The difference in positive cases reported on June 12 versus July 12 is over 2,300, whereas the difference in cases from May 12 versus June 12 is 377.

GOVERNOR UPDATE: Santa Cruz Co. removed from watch list, power outages 'very likely' through Wednesday, Newsom says

San Quentin has reported 2,236 individuals who have tested positive for the virus, which is an increase of more than 60% to the county's current total non-prison cumulative number.

Look at the chart below to see the case difference per month for each county, along with those numbers for the total Bay Area.

App users: For a better experience, click here to view the graph in a new window.

County case numbers for all of California were incomplete earlier this month due to a computer database failure of the CalREDIE system, used to log COVID-19 test results. The issue reportedly began in late July because of a server outage.

"Simply put, the CalREDIE system was not built for this volume of data," Health and Human Services Secretary Dr. Mark Ghaly said at a briefing earlier this month. "In order to create a lasting solution, we are accelerating the development of a new laboratory reporting system for COVID-19."

As the updated numbers come in, daily case numbers are rising, in part due to the added data. Daily new cases across the Bay Area have been steadily rising since late June, so the database failure only accounts for part of the increase. Part of the rise in cases during the past two months could also be from increases in testing across the area.


App users: For a better experience, click here to view the graph in a new window.

Last week Dr. Sonia Angell, director of the California Department of Public Health, resigned. While the reason is not immediately clear, some suspect it has to do with the CalREDIE data inaccuracies. The California Department of Public Health is in charge of collecting the COVID-19 test results.

RELATED STORIES & VIDEOS:
Copyright © 2020 KGO-TV. All Rights Reserved.