How is FeLV different from typical viruses?
One reason scientists have not yet found a cure for feline leukemia is because the virus acts differently from most other viruses. When a normal virus attacks a cell, it enters the cell's nucleus, the “command center,” and takes control. Effectively, the virus hijacks the cell, forcing it to obey the virus's commands. Once it has assumed control, the virus begins to multiply, commanding the captured cell to assist in producing thousands of duplicate copies of the virus. When the new viruses are complete, they burst out of the cell, destroying it.
Feline leukemia hijacks cells the same way, but unlike normal viruses, FeLV may command its victim to do more than one task. The captured cell will become either a virus producer or a cancer producer. When an FeLV-captured cell becomes a virus producer, it is not destroyed when it completes a set of new viruses. Instead, the cell lives on to produce more batches of viruses. Because the producers are not destroyed, FeLV progresses much faster than many other diseases.
When captured cells become cancer-producers, a transformation uncommonly caused by most viruses, the cells mutate and cluster together, causing tumors. Scientists still do not know why FeLV creates cancerous cells.