“We’ve accidentally ended up compromising our own immune system to get fatter chickens.”
China fed colistin to pigs and chickens for decades as a growth promoter. The resulting MCR-1 gene makes E coli at least twice as resistant to human blood serum and 62% more resistant to the peptides our innate immune system relies on. The meat industry got cheaper weight gain and everyone else got a weaker first line of defence. Britain still opposes banning preventative mass medication of farm animals, a year after the EU did it.