A medical fluid connector, having a first body with a tube section with an inlet and a first thread, a second body with an outlet and a second thread that engages the first thread to move the first and second bodies between closed and opened positions. The second body has a third thread that is configured to rotate in the opposite direction in relation to said first and second threads. The connector has a closure cap with a fourth thread that, in a delivery state of the fluid connector, is detachably screwed to the third thread of the second body, wherein the fluid connector assumes the open position, and wherein the outlet is closed off in an air-permeable and liquid-tight manner by means of the closure cap.