INDIANAPOLIS (AP) — Local leaders should decide if schools should be closed and large gatherings canceled, Indiana's governor said Friday, even as his top health official acknowledged the uncertainty over how widespread coronavirus infections are in the state.

Dozens of school districts around the state have announced they’ll be closing for at least two weeks and the Indiana high school boys basketball tourney was called off Friday. Some museums and libraries also are closing, and religious services are being canceled to avoid large gatherings.

Gov. Eric Holcomb said people need to take precautions seriously to help slow the spread of the virus.

“What we’re trying to prevent is a real run on our hospital and health care system that draws more resources,” he said.

For most people, the new coronavirus causes only mild or moderate symptoms, such as fever and cough. For some, especially older adults and people with existing health problems, it can cause more severe illness, including pneumonia. According to the World Health Organization, people with mild illness recover in about two weeks, while those with more severe illness may take three to six weeks to recover.

Indiana schools are being allowed to close for up to 20 days this school year without having to make up that classroom time, but Holcomb hasn’t followed the governors of Ohio and Michigan in ordering statewide school closures.

Holcomb said he believed local school officials should make closing decisions based on considerations such as food distribution, transportation and child care availability.

“In this case, it may be more of a hodgepodge for the time being. That may best serve the citizens of those individual communities,” Holcomb said. “If we start to see community spread, then we’re going to get more and more involved.”

Indiana had 12 confirmed COVID-19 cases as of Friday.

State Health Commissioner Dr. Kris Box said Indiana is probably actually close to the 1% statewide infection rate estimated by Ohio’s state health director. That’s potentially about 70,000 people infected in Indiana as a top federal health official said the government is failing to account for what could be thousands of additional infections because of ongoing problems with testing.

But Indiana has not yet seen widespread serious illness such as in Washington state where at least 31 people have died from the disease.

Box said he suspects there are more cases than the state has recognized so far.

“It’s not a Washington state thing, because we don’t have that kind of burden on a health care and hospital system right now,” Box said, referencing the high number of elderly people infected in a nursing home in the Pacific Northwest.

More than a dozen colleges across the state — including Indiana, Purdue and Ivy Tech — are extending spring breaks and temporarily canceling classroom instruction to curb the spread of the virus.

Many school districts in the Indianapolis area, including all in Marion and Hamilton counties, are closing or switching to online classwork. Others in Evansville, Bloomington, Anderson and the South Bend area are doing the same.

The Children's Museum of Indianapolis announced would close, beginning Saturday through March 28.

The NCAA and the Big Ten have called off basketball tournament games scheduled for Indianapolis. The Indiana High School Athletic Association put the brakes on the boys basketball tourney after making plans Thursday to play regional games at 16 sites around the state with each team limited to 75 admissions.

“With the number of schools now taking extended breaks from school it has become impossible to complete the tournament series as originally scheduled,” IHSAA Commissioner Bobby Cox said.