CONTRA COSTA COUNTY, CA — Effective Tuesday and for the next two weeks, Contra Costa County public health officials are recommending that groups cancel large gatherings where 50 or more people are within arm's length of each other, including concerts, sporting events, celebrations, conventions, religious services and other church gatherings.

The new guidelines came as the county's Board of Supervisors declared a state of emergency in the county to deal with the potential spread of the new coronavirus, or COVID-19. As of Tuesday, a total of 10 Contra Costa County residents have tested positive for the new coronavirus. Of those, four were known to have had contact with people who previously tested positive. Six had no recent history of travel outside the United States or known contact with a confirmed case. In addition, three confirmed cases from outside Contra Costa have been treated at hospitals in the county.

The virus that causes COVID-19 is spreading from person-to-person, not only in Contra Costa County. Someone who is actively sick with COVID-19 can spread the illness to others. That is why the U.S. Centers For Disease Control and Prevention recommends that these patients be isolated either in the hospital or at home (depending on how sick they are) until they are better and no longer pose a risk of infecting others. To slow the spread locally, officials with the county's public health department, Contra Costa Health Services, were scheduled to announce new public guidance in a briefing at 2 p.m. Tuesday. [Officials with CCHS said the briefing would be live-streamed on Contra Costa Health Services' Facebook page at 2 p.m. but it appears the video was delayed; if it becomes available we will share it here.]

The new guidelines are in addition to those released Friday by the county for people 50 and older, as well as people of all ages who suffer from serious illnesses such as diabetes, cancer, cardiovascular disease, lung disease or immunosuppression. Friday, the at-risk community members were advised to avoid mass gatherings, such as parades, sporting events or concerts.

"CCHS is releasing updated health guidance to protect the community from novel coronavirus (COVID-19)," CCHS Spokesman Karl Fischer said Tuesday. "The updated guidance includes specific actions recommended for people at high risk of severe disease, community gatherings, businesses and employers, schools, public transit and the general public."

Don't miss local and statewide news about coronavirus updates, developments and precautions. Sign up for Patch alerts and daily newsletters.

Organizers are encouraged to cancel or postpone events for, or attended by, older adults or others who are at higher risk for severe illness. Those considered at higher risk are people 50 or older, as current evidence indicates that the risk of severe illness from the new coronavirus increases with age; and people of any age who have underlying medical problems such as heart disease, diabetes, cancer, or chronic lung diseases like Chronic Obstructive Pulmonary Disease (COPD).

In adopting the emergency proclamation Tuesday, Board of Supervisors Chair Candace Andersen, said: "The new coronavirus or COVID-19 presents our community with a challenge. While I urge you to be prepared, it is certainly not a time to panic. Following our health officials' guidelines will help prevent the spread of disease. The County and Contra Costa Health Services will continue to offer guidance and resources. Meanwhile, there is much each and everyone one of us can do to keep our families and communities well. It will take all of us working together." In voting unanimously in favor of the county emergency proclamation, supervisors said "everyone plays an important role."