Perhaps some low hanging fruit for pandemic prevention would be better disinfectants. Bleach can kill 99.999% of pathogens, but it causes nasty fumes and irritation on skin contact. If you can get the same results as bleach with reduced negative side effects, it should result in more people using it in more situations. There's a new disinfectant called Steriplex SD that seems promising.
Another thing worth considering is that more people might do bio-hacking at home if sterilization were less of a pain. This could increase or decrease risk depending on your perspective (more potentially competent counter-agents, e.g.)
The problem with such things is that bleach (and alcohol) kill everything. If you make something that is safe for humans, the mechanism that protects our cells could probably work for the infectious agents as well.
The FHI's mini advent calendar: counting down through the big five existential risks. The second one is a new, exciting risk: synthetic biology.
Synthetic biology
Current understanding: medium-low
Most worrying aspect: hackers experimenting with our basic biology
Synthetic biology covers many inter-related fields, all concerned with the construction and control of new biological systems. This area has already attracted the attention of bio-hackers, experimenting with DNA and other biological systems to perform novel tasks – and gaining kudos for exotic accomplishments. The biosphere is filled with many organisms accomplishing specific tasks; combining these and controlling them could allow the construction of extremely deadly bioweapons, targeted very narrowly (at all those possessing a certain gene, for instance). Virulent virus with long incubation periods could be constructed, or common human bacteria could be hacked to perform a variety of roles in the body. And humans are not the only potential targets: whole swaths of the ecosystem could be taken down, either to gain commercial or economic advantages, for terrorist purposes, or simply by accident.
Moreover, the medical miracles promised by synthetic biology are not easily separated from the danger: the targeted control needed to, for instance, kill cancer cells, could also be used to target brain cells or the immune system. This would not be so frightening if the field implemented safety measures commensurate with the risks; but synthetic biology has been extremely lax in its precautions and culturally resistant to regulations.