One day after reporting the largest one-day increase in deaths and new cases since the coronavirus pandemic began, Los Angeles County officials announced 15 more deaths and 663 more cases of COVID-19 Sunday.

The county now has 5,940 confirmed cases of COVID-19 -- the disease caused by the virus -- and 132 people have lost their lives.

The numbers were even worse Saturday, when 28 deaths and 711 new cases were added to the toll.

Of the 15 deaths confirmed Sunday, 11 had underlying health conditions and 10 were over the age of 65, according to the Los Angeles County Department of Public Health. Two were between 41 and 65 and one was between 18 and 40.

Two deaths were reported by the city of Pasadena, which has its own health department.

"Each death represents a person, not just a number, and I am so sorry for every family member and loved one lost to the COVID-19 pandemic," said Dr. Barbara Ferrer, director of public health. "We have some very difficult days ahead and now is the time for all of us to redouble our physical distancing efforts and look after our neighbors, friends, and families who may be at the highest risk for serious illness from COVID-19. ... If you are elderly, have underlying health conditions or are pregnant, please make sure you are staying home at all times and allowing others to shop for your essential goods. As we all work together to slow the spread, we need to also do our best to make sure our most vulnerable are supported so they can safely remain home."

Ferrer said 1,257 people who tested positive for COVID-19 -- or 21% of the cases -- have been hospitalized at some point during their illness.

Testing capacity continues to increase in L.A. county, with almost 31,000 individuals tested and 14% of people testing positive.

County officials said Sunday that three more COVID-19 mobile testing sites would open this week, at Martin Luther King Jr. Community Hospital, in East Los Angeles and Santa Clarita.

In addition, the officials said the county is in discussions with AltaMed to bring several urgent care facilities to underserved areas.

The pandemic has created a burden for essential workers trying to care for children, but on Saturday, Gov. Gavin Newsom addressed the issue by signing an executive order that subsidizes childcare for those workers. The order allows the California Department of Education and California Department of Social Services to waive certain requirements to allow childcare and after-school programs to serve essential workers, including healthcare professionals, emergency responders, law enforcement and grocery workers.

It also allows the state to take advantage of new federal pandemic provisions of the Supplemental Nutrition Assistance Program (SNAP) to ensure children receive nutritious meals at low or no cost.

The two agencies are required to determine how the order will be implemented no later than Tuesday.

Emergency responders are among the essential workers being hardest hit by the coronavirus. As of Friday, 43 Los Angeles Police Department employees had tested positive for COVID-19 and 13 members of the Los Angeles Fire Department had tested positive, said Jessica Kellogg of the Los Angeles Emergency Operations Center.

"One LAPD employee has recovered and returned to full duty, two individuals are hospitalized, and all other individuals are self-isolating at home and recovering," Kellogg said. "Two LAFD employees have recovered and returned to duty, with one member who is currently hospitalized and being treated. The remaining 10 employees are recovering at home."

The spike in county numbers comes one day after Ferrer warned residents to brace for more staggering numerical increases in coming weeks as testing capacity improves.

The number of cases across Los Angeles County grew by roughly 500 per day last week. But Ferrer said that as more testing comes online, the number of confirmed cases will likely jump to 1,000 daily by this week -- given that roughly 10% of people who are tested turn out to be positive, and the county expects to soon have capacity to test 10,000 people a day.

"We want to be prepared for that," Ferrer said. "I think that it's very accurate that at some point next week we will start reporting that big an increase in the number of cases, because thankfully we're able to actually test more people and make sure that people who are tested have the opportunity, if they are positive, to isolate themselves and not infect others and identify their close contacts, who will quarantine themselves and also not potentially infect others."

The health department also said Saturday that "emerging evidence suggests that there may be a significant number of people infected with COVID-19 who are asymptomatic and capable of spreading the virus to others. New guidance from the Centers for Disease Control and Prevention (CDC) reminds us we need to use universal precautions all the time -- assuming that each of us can infect others even when we aren't sick, and that others can infect us. Along with physical distancing, frequent handwashing, and remaining home when ill, the CDC is recommending that the general public wear non-medical face coverings when interacting with others while obtaining essential supplies and services.''

The ability of the virus to spread even before patients develop symptoms has led to increasing recommendations that residents wear some type of non-surgical mask or face covering when they go out in public. Ferrer and Los Angeles Mayor Eric Garcetti have both touted the benefits of people covering their faces to prevent a spread of droplets that can spread the virus from falling on surfaces or on other people.

Officials continued to stress that residents should not purchase hospital-grade masks, which are in short supply and desperately needed in hospitals.

Ferrer said people can use scarves or other fabric, suggesting that people go online for instructions on how to fashion a homemade mask.

She again noted that wearing such a face-covering does not free people from the need to remain at home as much as possible and practice social-distancing and hand-washing.