Virus and mite wiping out millions of bees worldwide: study

The video explains the presence of the deformed wing virus in bees, which is generally benign, affecting about 10% of the population. However, the introduction of the varroa mite changes this dynamic. The mite feeds on the bees' blood, leading to the disappearance of innocuous viruses and the proliferation of a lethal strain of the deformed wing virus. As a result, the frequency of the virus in bee colonies increases dramatically from 10% to 100%.

What is the lethal strain that fills the bee cells after infestation?

What is the range of the frequency of the formed wing virus in bees due to varroa mite infestation?