The coronavirus is spreading across the globe rapidly, and officials at the US Centers for Disease Control and Prevention have said its a matter of when–not if–the virus will spread within the Sates. Communities have been urged to prepare for the virus, which has already killed thousands and sickened tens of thousands around the globe.

The spread of the coronavirus in the United States could have a profound impact on the daily lives of Americans. According to the CDC, schools, businesses, hospitals, and first responders would see the biggest impact. Dr. Nancy Messonnier of the CDC said during a briefing yesterday, “We expect we will see community spread in this country. We are asking the American public to work with us to prepare in the expectation that this could be bad.”

On Thursday, California Gov. Gavin Newsom held a press conference to address how a patient in Sacramento could be the first person to have contracted the virus in an unknown way – called a “community spread” of the disease.

“We have been in constant contact with federal agencies. We have history and expertise in this space. We are not overreacting, nor are we under-reacting,” Gov. Newsom said.

The CDC has been referring to guidance on how to deal with flu pandemics, in a document called “Community Mitigation Guidelines to Prevent Pandemic Influenza United States 2017.” It’s the “blueprint” for community interventions, and the agency is adjusting its recommendations to the specific circumstances of the coronavirus outbreak, officials said.

The document draws from the findings of nearly 200 journal articles written between 1990 and 2016, and it includes a summary of lessons learned from the response to the 2009 H1N1 pandemic, which killed hundreds of thousands globally. [CBS]

Dr. Anne Schuchat, CDC’s principal deputy director, said on Wednesday, “The trajectory of what we’re looking at over the weeks and months ahead is very uncertain, but many of the steps that we have taken over the past 15 years to prepare for pandemic influenza and our experience going through the 2009 H1N1 pandemic of influenza remind us of the kinds of steps that our health care system, our businesses, our communities and schools may need to take. It’s the perfect time for businesses, health care systems, universities and schools to look at their pandemic preparedness plans, dust them off and make sure that they’re ready.”

Widespread transmission of the coronavirus could result in schools, childcare centers, and colleges closing down. People would also likely be asked to work from home, to prevent further community spread of the virus.