Unfortunately this is not the responsibility of the shelter. Here is a link that will help https://www.fairfaxcounty.gov/wildlife/injured-and-orphaned-wildlife
Like the other two posters mentioned, Vienna takes care of their own corresponding area with at time the help of the Fairfax animal control or the wildlife help. Make a call to Vienna first.
The Town of Vienna has their own Animal Control so you may want to contact them first. Usually adult foxes cannot be treated due to concerns about rabies exposure and limited number of veterinarians trained to handle wildlife.
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