Assuming that is in fact the vaccine in the previous shot, this would likely be the unwitting test subject in question ready to be infected. In earlier X-Files episodes, test subjects were strapped down with a wire mesh style material. While that has changed slightly here for obvious effect, the basic premise remains the same. It's not clear who the subject is in this case. It could be a minor character, a complete nobody, or a key player, but there's really no way to tell. Regardless, the key is that humans are still being forcibly exposed to the substance in a test/lab setting, as the mass infection of the populous was to involve bees carrying the virus.