Dallas Declares State of Emergency Over West Nile Outbreak

In a summer that has already seen record high temperatures, widespread drought, and an outbreak of whooping cough, what’s the latest anomaly to add to the list? West Nile virus.

The outbreak of the mosquito-borne illness has become so serious that Dallas Mayor Mike Rawlings declared a state of emergency on Wednesday, clearing the way for the city to start taking measures to quell the spread, including aerial spraying of insecticide over the hardest-hit neighborhoods.

At least 190 people in Dallas County are infected, and 10 have died from the mosquito-borne illness. The number of cases is up nationwide, according to CNN, but the brunt of the uptick is in the South, with about 80 percent of the reports coming from Texas, Mississippi, and Oklahoma. It’s not clear exactly what is behind the increase, but experts say it is most likely a combination of a warm winter, a wet spring, birds, and human behavior.

Texas has seen a statewide spike in the illness, with the number of reported cases rocketing up to 381 this year from just 27 in 2011, the Los Angeles Times reports. About 95 percent of mosquitoes tested in the Houston area were found to be carrying the virus.

West Nile infections, characterized by flu-like symptoms—including fever, headache, nausea, or rashes—may require hospitalization in serious cases, and in rare instances it is linked to neurological illnesses like meningitis. There’s no vaccine or treatment for the virus, but the Centers for Disease Control and Prevention recommends taking preventative measures like using insect repellent and getting rid of mosquito breeding sites to limit exposure.