Deformed wing virus (DWV) is one of the viral diseases associated with Varroa mite infestations. Although the disease is also found in colonies not infected with Varroa, it appears to be both more common and more destructive in colonies where mites are well established.
Other things can cause an occasional case of deformed wings and a diagnosis is impossible without laboratory tests. However, if you see a young bee with distorted, misshapen, twisted, or wrinkled wings, there is a good chance you are seeing the results of deformed wing virus.
In untreated hives, the Varroa mite population skyrockets in late summer and early fall. The mites had all spring and early summer to build up and now, when the drones are being evicted and the honey bee population is shrinking, the number of mites may overwhelm the number of bees. When the viruses also become concentrated in the remaining bees, symptoms are more likely to be apparent to beekeepers.
Bees with deformed wings do not live very long. The one shown below wandered out of the hive this morning and was fluttering her misshapen wings and running in a circle when I found her.