Citrus tristeza (CTV); Quick decline (Closterovirus Citrus Tristeza Virus) is a viral pathogen. It was first detected in Florida in 1950.
Citrus tristeza virus is a viral species of the Closterovirus genus that causes the most economically damaging disease to its namesake plant genus, Citrus. The disease has led to the death of millions of Citrus trees all over the world and has rendered other millions useless for production. The virus is transmitted most efficiently by the brown citrus aphid.