Thomas Duncan died earlier this month and it is still unclear how the nurses contracted the virus while wearing protective clothing.
The news of the two nurses' recoveries comes a day after a new US infection, the first in New York.
Craig Spencer, 33, began to feel tired on Tuesday and developed a fever and diarrhoea on Thursday. He had recently returned from Guinea where he had been working for medical charity, Medecins Sans Frontieres.
Dr Spencer is being kept in isolation at New York's Bellevue Hospital.