For the film: With people deathly afraid of getting infected by just a single drop of blood on the skin, why is the predominant form of gun still one that fires small pieces of metal at high velocity, splattering blood everywhere? It seems like the situation would provide a good impetus for the development of guns which use fire, electricity or other such things. The level of technology we see with pocket dimensions and gravity manipulation seems like laser guns would fit right in.
Well, the Daxus government wants infections so they can justify their takeover. It's a case of Dystopia Justifies the Means.
Also, the hemophages may be Hard To Kill using fire or electricity, due to virus being modified for a Super-Soldier program.