Can viral infections be diagnosed by a high white blood cell count assuming blood cancers are not a factor?

Blood Cells: Often viral infections lead to low white blood cell counts not high.

Need a work up: Not enough information. There are many viruses that cause human disease and investigators keep finding new ones. A high white count may occur as a result of multiple causes. Thus , one needs to have this looked at with a careful history, physical exam and guided diagnostic work up. Sometimes finding the answer can be slow.

Yes: Viral infections can cause relatively high white cells, mostly lymphocytes. Look at the whole blood counts, white, red cells, size and shape. And platelets. Any nodes, fever, sweats, weight change, bleeding, sore throat....? Do not put your self in a corner. Think outside the box. Discuss with your md.