What is Jared Diamonds argument for why no lethal crowd epidemics developed in the Americas? Can someone please answer this I don’t understand

Explanation:

The three people talking in the hospital room were already stressed out from having to cope with a mysterious illness, and it didn’t help at all that they were having trouble communicating. One of them was the patient, a small, timid man, sick with pneumonia caused by an unidentified microbe and with only a limited command of the English language. The second, acting as translator, was his wife, worried about her husband’s condition and frightened by the hospital environment. The third person in the trio was an inexperienced young doctor, trying to figure out what might have brought on the strange illness. Under the stress, the doctor was forgetting everything he had been taught about patient confidentiality. He committed the awful blunder of requesting the woman to ask her husband whether he’d had any sexual experiences that might have caused the infection.  As the young doctor watched, the husband turned red, pulled himself together so that he seemed even smaller, tried to disappear under his bed sheets, and stammered in a barely audible voice. His wife suddenly screamed in rage and drew herself up to tower over him. Before the doctor could stop her, she grabbed a heavy metal bottle, slammed it onto her husband’s head, and stormed out of the room. It took a while for the doctor to elicit, through the man’s broken English, what he had said to so enrage his wife. The answer slowly emerged: he had admitted to repeated intercourse with sheep on a recent visit to the family farm; perhaps that was how he had contracted the mysterious microbe.

secretly cooperate with one another.

answer: /hbv

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