The apparel chain said it learned March 5 that the staffer was confirmed to have the disease, which has prompted other U.S. companies to close their offices or ask employees to work remotely.
"The individual was not in the office today and is currently recovering at home," the company said Thursday in a notice sent to a recent visitor. "We have decided to close our New York office and are asking employees to work from home until further notice."
Gap's global headquarters are in San Francisco but the company, which also owns Old Navy and Banana Republic, has product development offices in New York's Tribeca neighborhood (55 Thomas Street).
A Gap spokeswoman couldn't immediately be reached for comment.