"Per guidance from public health officials, the contact tracing process has begun to notify everyone who may have come into contact with the Governor's family member during the potential infection window," the statement said.
Murphy does not qualify as an exposed close contact, but has canceled in-person events and is voluntarily quarantining out of an abundance of caution.
Murphy tested negative during a regularly-schedule COVID-19 test on Wednesday morning.
"From the beginning, the Governor has taken every precaution to limit the spread of COVID-19. Today's exceedingly cautious steps are part of that ongoing commitment," the statement said.
Murphy was previously in quarantine in October after two staff members tested positive for COVID-19.
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