The swift push in 20 states and here in D.C. to mandate vaccination was met with much criticism. Mandatory vaccinations are always controversial, particularly in a case like this where sex is involved.
Some lawmakers appeared to be wholly sincere in their desire to push for vaccinations, including Texas Governor Rick Perry, who signed an executive order earlier this month to require them. (Legislators may block the requirement.)
The fact that the drug in question has only been on the market for a few months, and that Merck stands to profit greatly from its mandated use (it's quite expensive) and had been lobbying hard for it, naturally added to doubts -- even among vaccination supporters. Clearly, it will be better for the drug's use to be debated on its merits over a longer period of time.