LOS ANGELES (CBSLA) — County health officials Wednesday announced three new deaths linked to COVID-19, even as they backtracked on an earlier announcement that a child died from coronavirus, saying it’s possible the death was caused by something else.

Dr. Barbara Ferrer, the head of the county Department of Public Health, said the number of coronavirus cases countywide climbed over 800 and announced more stringent quarantine and isolation rules for people who either have the virus or are presumed to be infected.

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She said the newly issued order requires self isolation for any person who tests positive, is presumed to have COVID-19 or is in close contact with someone suspected of having the illness. The county is asking every resident to be prepared to quarantine or isolate if need be, said Ferrer.

The three new deaths were all people over age 65 with underlying health conditions. The deaths brought the county’s total to 13 — with Ferrer saying the death of a 17-year-old boy in Lancaster that was reported Tuesday is no longer considered a coronavirus case, pending a determination by the U.S. Centers for Disease Control and Prevention.

It’s not clear why officials ranging from the county’s chief health officer to the mayor of Los Angeles and the governor of California initially cited the case in their respective media updates Tuesday.

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The city of Long Beach announced 13 new cases not yet included in the county’s number, meaning the actual total in the county is 812.

Ferrer initially called the case “a devastating reminder that COVID-19 affects people of all ages.”

Though a Tuesday evening statement from the public health department said the teen’s fatality would require further evaluation by the Centers for Disease Control and Prevention.

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“Though early tests indicated a positive result for COVID-19, the case is complex and there may be an alternate explanation for this fatality,” the department said in a statement. “Patient privacy prevents our offering further details at this time.”