If you rent a cheap Airbnb house in Las Vegas, you might not be altogether surprised to find dead crickets in the garage. But a thousand vials of medical samples in several freezers – and a centrifuge? After the cleaner and one guest fell ill at a property in the city’s Sunrise Manor neighborhood last week, federal agents raided it and found a whole laboratory’s worth of scientific kit of the kind more useful to medical scientists than, say, drug dealers. Curious. Curiouser still, the house belongs to a Chinese national named Jia Bei (Jesse) Zhu. He is currently in...