Biggest problem is animal agriculture. The use of extremely aggressive antibiotics increases muscle growth, improves health and eventually leads to larger profi

Biggest problem is animal agriculture. The use of extremely aggressive antibiotics increases muscle growth, improves health and eventually leads to larger profit. 150 billion land animals raised yearly are a big evolutionary pool of bacteria. To become resistant to antibiotics takes much less time when you run the experiment in parallel 150 billion times per year, than a couple hundred million in humans. One strain, isolated in one of the 150 billion animals can become resistant and spread around the farm. If it goes unnoticed it can quickly spread over the country.