California public health officials say local authorities should test people for the coronavirus in “high risk settings” even if they don’t have symptoms, a change aimed at health care workers, prisoners and the homeless.

State officials believe the new guidelines are the first in the country to prioritize testing for people who don’t have symptoms. Until Monday, California followed guidelines from the U.S. Centers for Disease Control and Prevention that only those with symptoms should be prioritized for testing.

The new recommendation was outlined in a California Department of Public Health memo and was first reported by the Los Angeles Times.

“The higher risk settings for COVID-19 right now, since we aren’t having cruise ships anymore, are homeless shelters, jails and nursing homes,” said Dr. Bob Kocher, an adjunct professor of medicine at Stanford University and a member of Gov. Gavin Newsom’s task force aimed at increasing coronavirus testing. “For us to contain future outbreaks, we need to be exceptionally good at testing people in those settings.”

The new guidance comes after recent outbreaks in two California homeless shelters. Tuesday, officials in Los Angeles reported an outbreak at the Union Rescue Mission with at least 56 people infected. In San Francisco, an outbreak Multi-Service Center South resulted in 96 homeless people and 10 staff infected. Most did not have symptoms.

For most people, the new coronavirus causes mild or moderate symptoms, such as fever and cough that clear up in two to three weeks. For some, especially older adults and people with existing health problems, it can cause more severe illness, including pneumonia and death.

California is now testing an average of 14,500 people per day, up from an average of 2,000 per day at the beginning of the month. Newsom has said his goal is to test 25,000 people per day by the end of April.

California has more than 35,600 confirmed cases and 1,300 deaths, according to data compiled by Johns Hopkins University. Tuesday, Newsom reported a 3.8% increase in intensive care hospitalizations.

Still, the virus’ impact have not been as devastating as public health experts had feared, mostly because of the state’s mandatory stay-at-home order that has closed schools and nonessential businesses. While effective at slowing the spread of the virus, the order has led to more than 3 million people filing for unemployment benefits.

California’s new guidance is meant to help local public health officials, providers and laboratories prioritize who should be tested. The memo says the guidelines “will be reassessed on a weekly basis.”

“As testing capacity increases, testing should expand accordingly at the discretion of the Local Health Officer,” the memo says.