The theory that cancer could be caused by a virus began with the experiments of Oluf Bang and Vilhelm Ellerman in 1908 who first show that avian erythroblastosis (a form of chicken leukemia) could be transmitted by cell-free extracts.
A teoría de que o cancro podía ser causado por un virus xurdiu dos experimentos de Oluf Bang e Vilhelm Ellerman en 1908, que foron os primeiros que mostraron que a eritroblastose aviar (un tipo de leucemia) podía transmitirse por extractos libres de células.