Health officials believe people are contracting the virus through direct contact with infected fowl and say there has been no evidence so far that the virus is spreading easily between people.
The virus has been detected in live poultry in several food markets where human cases have been found, leading officials to think people are most likely contracting the virus through direct contact with infected fowl.
There is a kind of manufacturing, often with high components of craft work, which needs to be in urban areas because it is networked, depends on contracting and subcontracting arrangements, and often needs direct contact with customers.
The Health Protection Agency says the risk of contracting any illness is generally low, but people are advised to avoid coming into direct contact with floodwater.