Officials say they are trying to go back through the contact the inmate had with other inmates and staff members at the Nassau County jail in East Meadow.
The inmate is currently being treated and has been put in isolation.
Meanwhile in Suffolk County, all visits with inmates at correctional facilities are temporarily being suspended in order to limit the spread of the coronavirus in county jails. Attorneys, however, may still arrange to visit their clients.
Long Island has seen two deaths from COVID-19 and a total of 175 positive cases.
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