The first was at the H Mart in San Jose on May 21 between 7:15 p.m. and 9 p.m.
The was May 23 at Starbucks in Newark, on Newark Boulevard between 11:45 a.m. and 2 p.m.
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And the third was on May 25 at a Trader Joe's in Milpitas from 4:45 p.m. through 8 p.m.
The person traveled internationally and tested positive.
However, they never were hospitalized.
Health officials from Santa Clara and Alameda counties plan to address the case Friday morning.