SAN FRANCISCO (CBS SF) – The San Francisco Department of Public Health is warning residents about potential exposure to typhoid fever.

SFDPH reports that a restaurant worker a the Nordstrom Café at Stonestown Galleria has been diagnosed with the infectious disease.

READ MORE: 23rd Annual 'A Home For The Holidays At The Grove' Comes To CBS On Sunday, December 5th

An investigation is ongoing, but officials said the food handler likely contracted the disease overseas.

Anyone who ate at the Nordstrom Cafe within the Nordstrom store in the Stonestown Galleria in San Francisco on April 16, 17, 18, 20, or 27, 2013 may be at risk of exposure. SFDPH advises those individuals to see a healthcare provider right away if they start to experience symptoms such as fever, weakness, stomach pains, headache, nausea, vomiting, diarrhea, or loss of appetite.

READ MORE: Yuba County Agency Mulls Water Shipments to Bay Area Counties

Symptoms usually begin within 8 to 14 days after exposure, but could potentially appear for up to 30 days, according tho SFDPH.

Typhoid fever is an illness caused by the bacterium Salmonella enterica serotype Typhi. Although death is uncommon, typhoid fever can be severe and life-threatening. In the United States, 300-400 cases of typhoid fever occur each year, and most of those are acquired during international travel.

Nordstrom has set up two test labs for customers who ate at the cafe and are now feeling the symptoms, they are are located at the Franciscan Treatment Room on Bush Street and The Sutter Park Medical Foundation. San Franciscans with no medical insurance can visit San Francisco General Hospital’s Urgent Care Clinic.

Click here for more information about typhoid fever from the Centers for Disease Control.

MORE NEWS: 'Let it Glow' SF Lights Up San Francisco To Revive Pandemic-Stricken Downtown

(Copyright 2013 by CBS San Francisco. All Rights Reserved. This material may not be published, broadcast, rewritten, or redistributed.)