Randy McIlwain, NBC 5 News
Aerial spraying to combat West Nile virus infected mosquitoes begins again Wednesday night and Dallas County says the approach has been successful.
The Centers for Disease Control and Prevention sent five more scientists to North Texas on Wednesday to study the cause of the West Nile epidemic.
Two others from the federal agency arrived on Monday.
“They're helping to monitor and see if they can figure out what the environmental conditions are leading to such an increase in cases,” said CDC spokeswoman Kristen Nordlund.
The CDC is based in Atlanta.