"We have to do our part. This virus is often spread through asymptomatic people who are attending an event and assuming that they're fine," Garcetti said Wednesday.
The mayor reminded residents that trick-or-treating is discouraged in the city.
RELATED: Beverly Hills bans trick-or-treating on Halloween due to coronavirus pandemic
Beverly Hills bans trick-or-treating on Halloween due to coronavirus pandemic
L.A. County limits get togethers to no more than three households gathering outdoors for two hours or less, and everyone must wear a mask.
"Many of the infections are in small family and friend gatherings," Dr. Anthony Fauci told the Journal of the American Medical Association,
Fauci, the country's leading infectious disease expert, emphasized that 90 to 95% of the population need to wear masks. He says in countries such as New Zealand and Australia, where successful mask-wearing strategies are in place, new infections are sparse.
RELATED: 'You should not go trick-or-treating': California releases guidance for celebrating Halloween during pandemic
CA releases Halloween guidance, 'discourages' trick-or-treating
"If you don't want to shut down, at least do the fundamental basic things which are really the flagship of which is wearing a mask," Fauci said. "And that's what we really have to do. We can't have this very inconsistent wearing."
In Orange County, a UC Irvine study suggests COVID-19 could be far more prevalent than previously thought. It found more than 11% of county residents have antibodies for the virus - nearly seven times higher than previous estimates.
RELATED: Study: COVID-19 nearly 7 times more prevalent in Orange County than previously thought
Study: COVID-19 nearly 7 times more prevalent in Orange County than previously thought
In L.A. County, a rapid antigen testing pilot program is underway that could help slow the spread of the virus by providing faster results.
"These tests deliver quick results. In fact, I took one of these tests, and they said it took 15 minutes. I had my results back in two minutes," Garectti said. "Instead of costing $100 or $150, these tests can be as cheap as $5."
RELATED: LA unveils rapid antigen testing pilot program to help track COVID-19
LA unveils rapid antigen testing pilot program to help track COVID-19