The precautionary measures being enacted in Alabama to prevent the spread of coronavirus could be in place for months to come, according to state health officials.

State Health Officer Dr. Scott Harris said in a press conference Tuesday that the measures to limit coronavirus spread could be necessary for months to come, although information was limited because this particular virus was not known to occur in humans before December.

“I think with respiratory infections, a three- or four-month course is a reasonable place to start guessing how long it’s going to last,” Harris said. “We certainly hope with these mitigation strategies that it won’t last that long, but it’s just unknown because it’s a new virus.”

On Monday, Jefferson County announced new restrictions on restaurants, bars, private schools, day cares, and nursing homes. On Tuesday, Harris and Gov. Kay Ivey announced that those restrictions would also extend to Shelby, Tuscaloosa, Blount, St. Clair and Walker Counties, which immediately surround Jefferson County.

As of Tuesday morning, 20 of Alabama’s 36 confirmed cases of COVID-19 were in Jefferson County, which contains Birmingham, with eight more cases in the surrounding counties included in the order.

The order prohibiting bars and restaurants from serving food on-premises will be re-evaluated after one week, but health officials say they don’t know how long measures like that may be necessary.

“The information that we have to base our ideas on is from what we’ve seen in other parts of the world,” Harris said.

"We see what’s happened in China. Their cases probably started in at least early December maybe even in November, and then by early March they had seen a significant improvement, although that was with some really stringent measures to keep people from traveling and to keep people in [an] isolation situation.

“South Korea also has had a really robust response and their numbers have not, as many as they’ve had, their numbers have not been as high as perhaps people were anticipating earlier.”

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The full press conference with Harris is embedded below: