It's not a matter of if the novel coronavirus will spread throughout the United States, but when, said Centers for Disease Control and Prevention vaccine expert Nancy Messonnier.

"Disruption to everyday life might be severe," Messonnier, who is the director of the National Center for Immunization and Respiratory Diseases, told reporters Tuesday.

Messonnier said she told her children over breakfast that they will need to begin preparing for an escalated outbreak. Parents and caregivers, she said, should ask officials at their children's schools about plans for school dismissals, closures, and teleschool in case the virus spreads in their school districts.

"I contacted my local school superintendent this morning with exactly those questions," Messonnier said. "All of these questions can help you be better prepared for what might happen."

The coronavirus has already caused school and business closures in other countries currently seeing a surge in cases. For instance, the Italian health ministry ordered schools in northern Italy to close last week, and two schools in the United Kingdom will close for the rest of the week to conduct a “deep clean” after 34 students and faculty returned from a ski trip in Italy.

The CDC has sent virus test kits to 12 state health departments and is working to provide more. While the spread of the virus throughout the U.S. is inevitable, Messonnier said the CDC still doesn’t know how many cases will likely be as severe as those in other countries.

“We can have community spread in the United States and have it be reasonably mild, and we can have community spread in the U.S. and have it be very severe,” she said. “That is what we don’t completely know yet, and we certainly also don’t exactly know when it’s going to happen.”

Still, she said the CDC has been preparing for a viral outbreak for years and the agency knows that “it could be bad.” So far, the coronavirus has infected more than 80,000 people worldwide and killed more than 2,600.

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