Factual error: Hunt and the CDC Doc Stafford discuss an experimental vaccine for an outbreak to give to already infected people. That's not how vaccines work. You have to have it before you get sick to prevent you from having it or having a reduced response to the virus. What they're talking about is a cure/antiviral drug, not a vaccine.
Factual error: The opening scene is supposed to be a deer hunt, but if the police and coroner are from Philadelphia, there are many errors. Clothing is not right for November or early Dec., PA gun season, and there is not enough orange to meet game regulations. Philadelphia County is "archery only" and all surrounding counties are "shotgun only", so there would be no rifle or bullet in a murder staged as an accident. The key evidence is pollen from a leaf from a Southern Red Oak, not usually found in PA, but no leaves are on deciduous trees in PA in deer season, let alone leaves with pollen.
