Vast overuse of antibiotic medication is rapidly leading to the appearance of superbugs which render human treatments not just less efficient, but completely ineffective.
According to the World Health Organisation, the growing impotence of antibiotics is one of the top 3 health problems currently facing planet Earth (zombie infestation is not listed but may have been excised from the list in order to prevent a panic). Multiple highly resistant superbugs have appeared recently in Europe, and the crisis is coinciding with a massive decline in new antibiotic research by pharmaceutical companies, owing to the low profits involved.
It would seem that our only defense against the superbug apocalypse is being rapidly dismantled. While a virus would not have been affected by antibiotics in the first place, such medicine might at least have slowed the progress of a bacterial infection, if that were to be the source of our microbial massacre. But no. Our medicinal canon is being reduced to a popgun.