During World War II, he was a resistance fighter, rescuer, and member of the Danish Freedom Council.

Husfeldt signed the United Nations Charter in San Francisco in 1945 with Ambassador Henrik Kauffmann and Hartvig Frisch.

[2] Erik Husfeldt was born 20 December 1901 in Sumatra to Rasmine Henriette Jørgensen and Peter Carl Hansen.

Her parents were Elisabet Ruge and Kristofer Nyrop Varming, an architect and structural engineer.

Her parents were Elisabeth Brock Iversen and Niels Peter Petersen, a lessee.

[2] Husfeldt specialized in surgical operations using modern chest cavity procedures.

[2] He successfully treated twenty people with tumors and putrid lung abscesses, a difficult specialty before the introduction of penicillin.

[2] He developed a heart-lung machine for cardiopulmonary bypass surgery with four other physicians — H.C. Engell, Inge Rygg, Tyge Søndergaard, and F.

[1] From 1941 until the end of the war, he operated a resistance group of junior hospital doctors.

[1] He helped resistance fighter Jørgen Haagen Schmith (Citronen (Danish for 'the Lemon')).

[2] Husfeldt signed the United Nations Charter in San Francisco in 1945 with Ambassador Henrik Kauffmann and Hartvig Frisch.