Data collected by the Centers for Disease Control and Prevention, as well as state and local health departments in California, point toward signs that the coronavirus may have been infecting Americans weeks earlier than previously believed.

The first two cases of COVID-19 in California were officially announced on Jan. 26. In both instances, they were travelers coming from the outbreak epicenter of Wuhan, China. They had been in Los Angeles and Orange counties. However, there were two deaths of other people in the San Francisco Bay area from February and March that have scientists believing that the killer virus may have been in California as early as December.

"The virus was freewheeling in our community and probably has been here for quite some time," Dr. Jeff Smith, a physician and chief executive of Santa Clara County government said. Smith noted that COVID-19 was likely in California "back in December," as reported by the Los Angeles Times.

"This wasn't recognized because we were having a severe flu season," Smith explained. "Symptoms are very much like the flu. If you got a mild case of COVID, you didn't really notice. You didn't even go to the doctor. The doctor maybe didn't even do it because they presumed it was the flu."

"When public health [officials] tried to track down the start of the disease … we weren't able to find, specifically, a contact," Smith told county supervisors. "That means the virus is in the community already — not, as was suspected by the CDC, as only in China and being spread from contact with China."

The second coronavirus fatality in California was 68-year-old Azar Ahrabi, who died on March 9. The Los Angeles Times reported that health officials could not find a source for Ahrabi's COVID-19 infection.

Her family members said she stayed mostly at home, taking care of her mother. She seldom drove, and she walked to a local grocery store to shop. But she and her mother lived in a Santa Clara apartment complex in a neighborhood with a high density of international residents.

Ahrabi was checked into an emergency room on Feb. 20, and diagnosed with a nonspecific pneumonia. She was prescribed antibiotics and sent home. The next day, she was admitted to the intensive care unit.

Azar's son Amir Ahrabi asked doctors to test her for the novel coronavirus, but physicians told him that she didn't meet any of the qualifying criteria to be tested.

On March 6, a 70-year-old man was found dead in his home and he tested positive for coronavirus. He lived less than four miles from Azar Ahrabi, "essentially off the same main road with an interstate between them." His death was "never publicly announced, and county health officials did not answer questions about the case," according to the Times. This has doctors believing that there had already been a viral community spread.

To gain a better understanding as to when the coronavirus was first in California and the U.S., researchers are analyzing specimens from blood banks and other repositories to see if there are any antibodies in the samples.