The state of Virginia was one of the Thirteen Colonies in North America. It's first settlement, Jamestown, was the first permanent settlement built by the English in the modern United States. Northern Virginia in particular has built up the state's population significantly, as it contains many of the suburbs of Washington, D.C.. The Alexandria Safe-Zone is located there.
Not a lot is known about Virginia during the outbreak. It can be assumed that it followed the example of California, with state and local police being among the first responders, with these first responders being joined by military units if and when a state of emergency was declared.