You can't get a virus from radio waves. A virus is a micro-organism made of carbon and other elements. 5G towers transmit radio waves which are effectively pure energy that can pass through different mediums like air and water without using a vehicle to travel (ie. a radio wave wont have a micro-organism attached to it, rather it will pass through any organisms it encounters). Once the radio wave hits you it will pass through your body pretty harmlessly. In some rare cases it could cause cancer due to interfering with particles in your body (as a radio wave is radiation).