DALLAS (August 15, 2012)--Dallas Wednesday joined the list of North Texas cities that will use aerial spraying to combat to nation's worst outbreak of West Nile virus so far this year.

Dallas Mayor Mike Rawlings declared a state of emergency Wednesday and said the city would allow to the first aerial spraying of insecticide since 1966, when more than a dozen deaths resulted from encephalitis.

Aerial spraying for mosquitoes could begin as early Thursday evening.

Dallas County officials authorized aerial spraying last week.

More than 200 cases of the virus have been reported in Dallas County, and 10 people have died.

State Health Commissioner David Lakey asked North Texas mayors to advise the state by Wednesday on whether they want their cities sprayed from the air.