On March 18, shelter in place orders were issued by Yolo County (until April 7),[309] the city of Fresno (until March 31),[310] Napa County (effective March 20, until April 7)[311] San Luis Obispo County (until April 17),[312] and Mendocino County (until April 7).[313] The Department of Defense said the Navy's hospital ship USNS Mercy is being prepared for deployment in California, "to assist potentially overwhelmed communities with acute patient care".[314]