Having already been stung on the throat by one of these Asian giant hornets (known as 'tu fong' - dirt hornet in Chinese on account of their nest being built on the ground) while out hiking (my neck looked like I'd swallowed one of those junior sized footballs), I was persuaded to take some local hunters back to catch them. I didn't want to go anywhere near them, but they argued that they were a public safety hazard - a local school teacher had been killed a few years ago when he'd stumbled across a nest - so I reluctantly agreed to do my civic duty. As it turned out, there was an ulterior motive -- they use them to make a prized 'energy enhancing' alcoholic drink. 3-4 stings can reputedly be fatal but it would depend on your reaction - they are amongst the most poisonous insects on earth. The symptoms for me were acute pain -- the oft quoted 'hot nail' is pretty accurate but that's just the start of it -- it's then like a chemical pain bomb going off under your skin - shortness of breath, nausea, paralysis and pronounced swelling of affected area, faintness. The fainting is the worst, because having already read on the internet that they can be deadly, you don't want any of that 'fade to black' thing happening. My reaction was stronger the second time because I was stung twice by the same hornet. The fainting and nausea seemed to pass after 30 minutes, and that is probably the danger zone - but it hurts like hell for a good 4 hours. If you do get stung, seek medical attention and they'll give you an anti-histamine shot and you should be ok. I also found soaking the affected part in hot water seemed to relieve the pain during the first few hours, then icing it after that. If you encounter a nest, the technique, supposedly, is to crouch down, keep your hands down, and slowly move away. I ran, and one followed me, hovered for a second to suss out a point of attack, then latched onto my throat with its sticky feet and injected me. I kept running after that and no others followed - so I wouldn't dismiss running as an escape method entirely. Don't wear black clothing or perfume when you go hiking. If you see one flying around by itself -- I see them daily around my house - it's probably not a threat, just out hunting for food. Though they are curious, and routinely buzz around my ears, which still freaks me out. Their main food target is the larvae of other insects, especially bees, which they feed to their own larvae.