Obviously, nothing good. Yet we often hear that the era of antibiotics is nearing its end (I might have even used that phrase). So what does the end of the antibiotic era mean?
I don’t think we will have to worry about an Andromeda Death Strain wiping out ten of millions people in the U.S. It has been estimated that the advent of widespread use of antibiotics in the 1940s and 1950s saved around 400,000 lives per year in the U.S. (general improvements in sanitation and public health are about double that). So, if all bacteria were completely antibiotic-resistant, in today’s U.S., that would be around ~600,000 dead per year. But that assumes we’re not able to stop any bacterial infections using antibiotics. Even for the Mad Biologist, that’s far too pessimistic (which is really saying something).
It’s worth noting that the recent evolution* of transmissible colistin resistance and its association** with carbapenem resistance–meaning these organisms are untreatable with current therapies–only affects Gram-negative bacteria. So right there, we can, give or take, cut that 600,000 in half (for reasons, both molecular and ecological, I don’t really see VMRSA, vancomycin resistant methicillin resistant Staphylococcus aureus, as a burgeoning problem; that said, staph infections kill somewhere in the neighborhood of 20,000 per year in the U.S., even though there are drugs available for these organisms). But that’s also an overestimate. Even today, many infections are still treatable with older antibiotics. The problem is that a small fraction (today, anyway) are not. In a life-threatening situation, or ‘just’ one of great discomfort or suffering, one can’t afford to play the microbiological equivalent of Twenty Questions: we need, to use a phrase, the silver bullet, and we need it right now. So, with the rise of colistin and carbapenem resistance enterobacteriaceae (‘CCRE’–I just made this up), we’re probably talking on the low end, assuming some increase, thousands to tens of thousands of additional deaths in the U.S., with the worst case scenario–and an incredibly unlikely one–being somewhere north of 100,000 additional deaths.
That said, if ‘CCRE’ (and for that matter, ‘old-fashioned’ CRE) spread, it will be miserable. Some of those deaths will be people in the prime of their lives who otherwise would have been fine. Surgery will become more risky. Healthcare will cost more as additional infection control measures are implemented.
There’s also the cost of non-lethal infections:
Not only will CREs increase mortality rates, but if carbapenem-resistance establishes itself in the larger E. coli population, a significant fraction of commonplace urinary tract infections will become untreatable. The amount of misery this would cause would be significant–UTIs would be the new STD. And keep in mind, that there are already roughly 36,000 E. coli associated deaths per year in the U.S., which blows U.S. HIV/AIDS deaths out of the water.
So the antibiotic era will end, if it does, with a loud whimper, not a bang.
*This is evolution. Fucking get over it.
**Colloquially, you can think of this as ‘linked’, but that word has a very specific meaning for population geneticists.