The sect is not being blamed for the spread of the virus. Rather, critics are alarmed by the dangerous advice touted by its leadership, and point out just how irresponsible it was to encourage a large-scale gathering. This is not Islamophobia, it is common sense.
Moreover, its members do now pose a risk to others. Pakistan, a Muslim nation, has also held adherents in quarantine. The motivation is therefore public health, not sectarian agitations.