It has been a busy day on the USNS Comfort, a 69,000-ton hospital ship that sits alongside a pier in the Panamanian port of Colón, and is in the fourth week of its four-month humanitarian mission to Latin America and the Caribbean.

Military and volunteer doctors and dentists aboard the ship have treated 35,000 Central Americans since the middle of June, in the latest of a series of social and economic initiatives aimed at boosting US standing in the region.