Shelves where disinfectant wipes are usually displayed is nearly empty at a Target store on March 02, 2020 in Novato, California.

County officials said the patient was likely exposed during international travel from Feb. 11 to Feb. 21 on a Princess cruise ship that departed from San Francisco and traveled to Mexico. Placer County officials said the patient arrived at Kaiser Permanente Roseville Medical Center by ambulance on Feb. 27 and was in isolation at the hospital.

"We extend our deepest condolences to the loved ones of this patient," Placer County Health Officer Dr. Aimee Sisson said in a statement. "While we have expected more cases, this death is an unfortunate milestone in our efforts to fight this disease, and one that we never wanted to see."

The patient was an elderly adult with underlying health conditions, county officials said, adding that the person was the second confirmed COVID-19 case in the county and is now the first death related to the virus in the state.

As of Wednesday, there are 53 confirmed cases of COVID-19 in California, including 24 from repatriation flights. According to the Centers for Disease Control and Prevention, California has more cases of the virus than any other state.

Placer County, which is in northern California near Sacramento, is monitoring ten health care workers from the hospital, the county said, and five emergency responders who were exposed prior to the patient being placed in isolation. The county said none of them are exhibiting symptoms. The county said other passengers from the cruise may have also been exposed.

"While most cases of COVID-19 exhibit mild or moderate symptoms," Dr. Sisson added, "this tragic death underscores the urgent need for us to take extra steps to protect residents who are particularly vulnerable to developing more serious illness, including elderly persons and those with underlying health conditions."

The news comes after Vice President Mike Pence, who is leading the U.S. response to the COVID-19 outbreak, announced the country's tenth death. CNBC has confirmed that the tenth death was in Washington state, where all of the first nine deaths occurred as well.

"The state is working with federal officials to follow up on contact tracing of individuals that may have been exposed to provide treatment and protect public health," California Gov. Gavin Newsom said. "This case demonstrates the need for continued local, state and federal partnership to identify and slow the spread of this virus."

Earlier Wednesday, Los Angeles-area officials announced six new COVID-19 cases in the county over the past 48 hours, prompting that southern California county to declare a local emergency to help free up federal and state funding. Officials said at the announcement that there were no community spread cases in Los Angeles county, meaning that all cases could be traced back to a known or suspected source.