PORTLAND, Ore. — Oregon Gov. Kate Brown on Thursday morning announced new steps the state is taking to prevent the spread of coronavirus, including banning all large gatherings of 250 people or more statewide.

The ban is effective immediately and lasts until April 8. A gathering is defined as any event in a space in which appropriate social distancing of a minimum of 3 feet cannot be maintained.

This applies to organized events, but doesn't apply to stores, schools and shopping centers. She urged Oregonians to take personal responsibility at weddings and other social gatherings, including ensuring elderly and those with underlying health issues do not attend such events. 

The governor added schools should cancel all non-essential school-associated gatherings, like group parent meetings, field trips and competitions.

Check the latest closures and cancellations in the Portland/Vancouver area 

The OSAA has canceled all state basketball tournaments.

RELATED: These events in the Portland/Vancouver area are canceled due to coronavirus concerns

"Let me be clear: Coronavirus is in our communities. We should be prepared for thousands of cases in Oregon," Brown said. "These steps will save lives."

Jennifer Vines, Multnomah County's heath officer, said the is no vaccine or cure for coronavirus, which is why social distancing and "flattening the curve" is the only tool we have to slow the virus' spread.

RELATED: What's 'flatten the curve' and what does it have to do with minimizing the growth of the coronavirus?

In the workplace, the governor recommends employers implement distancing measures, including increased physical space between employees in offices and worksites, limited in-person meetings, limited travel and staggered work schedules.

Visitor limitations announced earlier this week at long-term care facilities remain in place.

RELATED: Oregon issues new guidelines to long-term care facilities in response to COVID-19

Multnomah County Chair Deborah Kafoury announced at the press briefing that the county has declared a state of emergency in response to the coronavirus.

"We know the metro area is particularly vulnerable because people come together here," she said. She added that a surge of cases could quickly overwhelm Multnomah County's health care system. 

Mayor Ted Wheeler also announced Wednesday the City of Portland is under a state of emergency. 

"This morning I declared a state of emergency to give us the flexibility and powers we need to support our county and state partners to properly address the threat of infection and harm," he said.

"We've suspended service disruptions of water bureau and environmental services" to assist everyone in the city, he announced.

He added that "Portlanders have always looked out for each other" and now is the time to step up efforts to ensure our neighbors are safe.

RELATED: Coronavirus in Oregon: By the numbers

Oregon Health Authority officials estimate there are about 150-250 cases in Oregon right now. With cases potentially doubling each week, this could mean 75,000 cases in Oregon by mid-May, if we don't implement social distancing policies such as the large crowd ban. 

The state still has a capacity of about 80 COVID-19 tests per day, but that could change in the future, according to OHA. The number varies for private labs.

RELATED: What's the process like for getting a coronavirus test in Oregon? Are the tests free?

"We are concerned about our testing capacity," Brown said. "We’re working with HHS and federal partners, but the federal government is the only one who can expand our testing capacity. We are calling on them to do that." 

RELATED: Timeline: Coronavirus in Oregon and Washington

On Wednesday, state health officials had announced six new COVID-19 cases in Oregon, including two men at a veterans nursing home. The new cases bring Oregon’s statewide total to 21 across 10 counties.

In Washington, Gov. Jay Inslee on Wednesday announced a ban on gatherings of more than 250 people in three counties. Seattle’s sports teams have either canceled home games or announced they will be played without fans in attendance.