(CNN) Officials at the US Centers for Disease Control and Prevention have warned that it's not a question of if, but when the novel coronavirus will spread in the United States -- and communities are urged to prepare for the virus that has already killed thousands and sickened 10s of thousands more worldwide.

How could the possible spread of coronavirus change our daily lives? Schools, businesses, hospitals and first responders could all be impacted, according to the CDC

"We expect we will see community spread in this country," Dr. Nancy Messonnier, director of the CDC's National Center for Immunization and Respiratory Diseases, said during a press briefing Tuesday.

"We are asking the American public to work with us to prepare in the expectation that this could be bad."

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.

"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," Dr. Anne Schuchat, CDC's principal deputy director, said during a press conference at the White House on Wednesday.

"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."

Some schools and social events could shut down

Widespread transmission of the coronavirus could impact schools, child care centers, colleges and group events, such as concerts, festivals, and sporting events, according to the CDC's 2017 document.

For instance, the document notes that "social distancing measures" for schools, workplaces and gatherings "can reduce virus transmission by decreasing the frequency and duration of social contact among persons of all ages."

In schools, that could involve dividing classes into smaller groups of students and rearranging desks so students are spaced at least 3 feet from each other in a classroom, according to the document. That is, if the school remains open.

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Closing or canceling schools in response to public health concerns are decisions that districts typically have to grapple with and are already experienced in making.

For the novel coronavirus, "one of the questions that is scientifically out there that will govern or drive how school closures are calculated is to what extent children themselves carry or transmit this virus," Shah said. "Scientifically we need to have a better understanding of to what extent children are carriers or transmitters of the virus -- the point of that is, it's premature right now based on the science to make uniform claims about what school closures may look like."

Messonnier said on Tuesday that she talked to her family and told them, while they are not at risk right now, they should have a plan in case their lives are significantly impacted. She said she even called the children's school district to find out what would happen if schools needed to close.

"The data over the last week, and the spread in other countries, has certainly raised our level of concern and raised our level of expectation" of community spread, she said.

The CDC still doesn't know what that will look like, she added. Community spread could be reasonably mild or very severe.

You might be urged to work from home

The CDC has posted guidance on its website to help businesses and employers make decisions on work-from-home policies or flexible sick leave if there is significant spread of the coronavirus across the country.

Such guidance also includes how to respond if an employee gets sick.

The 2017 document noted that "social distancing measures that reduce face-to-face contact in workplaces might include offering telework and remote meeting options. Flexible sick leave policies should be implemented to encourage workers to stay home if needed."

Also according to the document, "CDC recommends environmental surface cleaning measures in all settings, including homes, schools, and workplaces, to remove influenza viruses from frequently touched surfaces and objects."

Yet overall, "what community spread looks like in the United States will vary greatly community by community. It might vary by time, it might vary by place," Shah said.

"Although we believe, according to the US CDC, that community spread is likely in the United States, the magnitude of that possibility as well as how it actually plays out, that will vary greatly between Washington state, Florida, Maine and any other state," he said, adding because of that, "there will not be a one-size-fits-all approach here."

First responders may have to act

With the spread of disease, health care systems could become taxed with high rates of hospitalizations and deaths -- and it could impact other critical infrastructure, too, such as law enforcement, emergency medical services and the transportation industry, according to the CDC.

Many state health departments are already in talks with emergency medical technicians, paramedics, firefighters and other first responders to plan how to handle sick patients while remaining healthy themselves in case the virus spreads through the community. Currently, there is no vaccine to protect against the coronavirus and no medications have been approved, yet, to treat it.

"What this looks like, again, will vary greatly community by community, city by city, state by state," Shah said.

The CDC has produced more than 23 guidance documents on infection control, hospital preparedness, personal protective equipment supplies and clinical evaluation and management to help first responders and health systems prepare for the possible spread of the disease.

Those preparations include making sure enough supplies are available for response efforts.

For instance, Shah said his colleagues at the CDC have already taken an inventory of their personal protective equipment -- such as gowns, masks and respirators -- and have put in an order for additional supplies, as have many other state health departments.

"We are anticipating what potential needs the health care system in Maine, and New England as a whole, may have for those supplies and we're trying to think as many steps in advance as we can," he said.

A call to stay informed

While federal, state and local health departments are staying on top of preparation efforts, Shah has several suggestions on how average Americans can get prepared, too.

"I'm recommending a few things. The first is to urge everyone to keep themselves and their families as healthy as possible. Exercise, eat a good diet, get a lot of sleep, wash your hands, do everything you can to stay healthy right now. The other thing we're recommending is that folks stay informed," Shah said.

"We really want to urge everyone to avoid dubious sources of information and stick with trusted sources like their state health departments or the US CDC," he said. "We're in a situation where fear and misinformation can spread more quickly than this virus."

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"These are really concrete things that everybody can start doing today, so that if we get into a scenario where the situation becomes more concerning nationwide, everyone is ready, not just health departments," Shah said.