The two people, a man in his 60s and a woman in her 30s, had recently traveled to countries that have widespread reports of COVID-19, officials said.
The diagnoses were described as "presumptive positive," with testing samples being sent to the Centers for Disease Control and Prevention for final confirmation.
County health officer Dr. Nichole Quick said the county recently improved its ability to perform COVID-19 testing and therefore "we expect to see more cases here in Orange County."
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Officials did not release a list of locations where the individuals may have visited in recent days.
The two new cases appear to be in addition to the county's first case, a man in his 50s who was said to have recovered after being diagnosed with the virus.
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