The space agency's Ames Research Center has gone into lockdown and staff have been told that it has gone into "MANDATORY telework status effective immediately and until further notice".
The research centre is located in Mountain View, California and serves as the home of a number of Nasa's biggest technology and spaceflight projects.
The restrictions now mean that staff have been forced to work from home. Those who do not have the right facilities at home or work in areas such as labs or other facilities requiring access to technical equipment will receive further information about what to do, the space agency said.
The employee was confirmed to have tested positive for coronavirus on 8 March, Nasa said.
"We believe the exposure at the center has been limited, but — out of an abundance of caution, and in consultation with NASA Headquarters and the NASA Chief Heath and Medical Officer in accordance to agency response plans — Ames Research Center will temporarily go to a mandatory telework status until further notice."
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