Especially the physical mutation rate has risen to a hopeless level

What had seemed a bilateral dispute between the United States and China over the renminbi’s exchange rate has mutated intoa general controversy over capital flows and currencies.

Indeed, the biology of the HIV virus, with its numerous strains, rapid rates of mutation and replication, its habit of attacking and exploiting the very cells designed to fend off infection, and its association with socially questionable but habitually common sexual behaviour, makes the rapid spread of the disease inevitable.