I agree with jiejie - I've been to the area 4 times, and there is little if any risk. If you want to be concerned about something in that area, watch out for the absolutely worst road traffic! I'm not talking heavy traffic, but terrible drivers - I've never seen worse. Most every driver in Vietnam does his own thing, and at great cost to human life! I'm terrified driving in a cab from the airport - last time the driver was texting while trying to avoid kids crossing the highway at night (very very very few traffic lights in Hanoi). Pedestrians are forced to walk in many streets/highways along with large buses, trucks, thousands of motorbikes, push bikes and hand carts. Most dangerous thing you could do would be to take a sleeperbus long haul to another city,