Authorities said there has now been a case of community spread of COVID-19 in Los Angeles County.

The revelation was made after county officials revealed that two more people tested positive for the virus.

One person’s infection could be traced back to Japan, but no source of exposure could be found in the second case,

be found, possibly representing the county’s first case of community transmission of the illness, health officials announced Monday.

The virus has killed more than 3,000 people and nearly 109,000 cases of the virus have been reported around the world, forced school closures and the cancellation of events.

There are now 16 cases in Los Angeles County.

“Community transmission is when we cannot identify a known source of exposure,” said Dr. Barbara Ferrer. “… With all of our cases, we are doing extensive investigations and identifying all of their close contacts. With both of these cases, to date we have identified no significant public exposures, but both of our new cases do have exposures to people who are known. … The two cases are now in isolation and all of their close contacts are or will be quarantined for up to 14 days from their last date of exposure.”

With the county now confirming its first possible case of “community transmission,” Ferrer said people who are pregnant, have underlying health conditions or are elderly should immediately begin “social distancing practices.”

“This would include avoiding non-essential travel, avoiding public gatherings or places where large groups of people are congregating and avoiding event venues,” Ferrer said.

She said those three groups of people are in danger of becoming more seriously ill if they contract the virus.

Officials in Pasadena, told Pasadena Now that the Centers for Disease Control provided the city’s health department with the names of 50 people that should self quarantine. It is not known how many of those people complied.

According to officials, there are no known cases of the Coronavirus in Pasadena.

Meanwhile, at Cal State Long Beach, university officials confirmed that 10 students are in self-quarantine after attending a “large event in Washington, D.C., at which three people subsequently tested positive for COVID- 19.” The college did not specify the event or confirm if they also attended the AIPAC conference, at which at least two people subsequently tested positive.

CSULB officials said the students are not showing any symptoms of the illness and the university is “in ongoing communication with them and we are closely monitoring their health status.”

Ferrer noted that any travelers returning from Italy, South Korea, mainland China or Iran are still being asked “to self-quarantine themselves for 14 days upon their return to the United States.”

She also said the U.S. Centers for Disease Control and Prevention is advising that people not go on any cruises.

There have been 22 deaths from coronavirus in the United States, while more than 3,800 people have died worldwide.