SAN RAMON, CA — As the holiday season kicks off and officials warn residents about limiting their interactions with others outside of their own household to curb the spread of the coronavirus, a tool developed by researchers from several universities lets you see your risk of exposure to the virus at an indoor gathering.
The tool shows the estimated chance — between 0 and 100 percent — that you’ll encounter at least one person with the coronavirus at an event in your county. You can reduce the risk by wearing a mask, distancing and gathering outdoors in smaller groups, researchers said.
As of Wednesday, if you were to attend an event with at least 15 people in Contra Costa County, there’s a 13 percent chance that someone in the group could expose you to the virus, according to the COVID-19 Risk Assessment Planning Tool. If your gathering has 10 people, that risk would be nine percent.
Two Georgia Institute of Technology professors led the creation of the project, and their team included researchers from Stanford University and the Applied Bioinformatics Laboratory.
“By default we assume there are five times more cases than are being reported,” the research team said in a statement. “In places with less testing availability, that bias may be higher.”
Access the COVID-19 Event Risk Assessment Planning Tool here.
Contra Costa County is in the most-restrictive purple tier of the state’s four-tiered, color-coded COVID-19 risk system. That means indoor gatherings are not allowed here, but the state permits outdoor gatherings with a maximum of three households, and safety precautions such as wearing masks and maintaining six feet of distance between others who are not in your household.
Public health officials in Contra Costa County and across the Bay Area recommend people keep gatherings “small, short, stable and safe,” and ideally close enough to home to avoid long-distance travel.
The safest way to celebrate is with virtual gatherings or at home, officials said.
There were 23,381 COVID-19 cases reported in Contra Costa County as of Wednesday and 260 deaths have been linked to the virus. That’s up from 22,625 cases a week ago, county data show. No new deaths have been reported in the past week.
Contra Costa County has seen an average of 13.4 new COVID-19 cases per day over the past week. The test positivity rate has been four percent, on average, over the past week. These data lag by a week.
Here’s the breakdown by community:
- Alamo: 183 cases, 0 deaths
- Antioch: 3,061 cases, 20 deaths
- Bay Point: 1,107 cases, 8 deaths
- Bethel Island: 17 cases, 0 deaths
- Brentwood: 984 cases, 11 deaths
- Byron: 32 cases, 0 deaths
- Clayton: 105 cases, 1 death
- Concord: 2,983 cases, 57 deaths
- Crockett: 29 cases, 0 deaths
- Danville: 551 cases, 5 deaths
- Discovery Bay: 199 cases, 0 deaths
- El Cerrito: 197 cases, 3 deaths
- El Sobrante: 395 cases, 2 deaths
- Hercules: 363 cases, 2 deaths
- Kensington: 18 cases, 0 deaths
- Lafayette: 239 cases, 0 deaths
- Martinez: 529 cases, 3 deaths
- Moraga: 103 cases, 1 deaths
- Oakley: 765 cases, 7 deaths
- Orinda: 177 cases, 11 deaths
- Pacheco: 78 cases, 1 death
- Pinole: 335 cases, 4 deaths
- Pittsburg: 2,481 cases, 19 deaths
- Pleasant Hill: 395 cases, 23 deaths
- Richmond:4,243 cases, 33 deaths
- Rodeo: 164 cases, 1 death
- San Pablo: 1,945 cases, 10 deaths
- San Ramon: 618 cases, 4 deaths
- Walnut Creek: 863 cases, 32 deaths
- Other: 222 cases, 2 deaths
Read more safe Thanksgiving gathering tips: Contra Costa Health Officer Issues Thanksgiving Guidance
See the full breakdown of Contra Costa County COVID-19 data.
Amber Fisher contributed to this report.