From a recent Healthcare article dated October 18 -
Crisp and cool fall weather has arrived for many parts of the United States but without ending the threat of mosquito borne illnesses like West Nile. Mosquitoes may be preparing to overwinter but there will be mosquito activity until the first hard frost. The five hardest hit states have not seen a hard frost yet, and some of the areas with the highest number of WNV cases may not see a frost at all.
Through October 16, the Centers for Disease Control (CDC) report 4,531 cases of illness due to West Nile virus. Neuroinvasive disease cases account for 51 percent of all reported West Nile illnesses, and there have been 183 deaths. Texas continues to experience the highest number of illnesses.
The Texas Department of State Health Services is reporting more West Nile illnesses than the CDC. It has received reports of 1,683 illnesses and 77 deaths. The Dallas / Fort Worth metro area is the center of the outbreak, although case counts are rising in both the Austin area and the Houston area.
The first freeze in the Dallas area occurs on average around November 22, according to the National Weather Service. Austin and Houston are farther south. Houston receives a hard frost, on average, about December 22. Mosquitoes will continue to be a concern in Texas for many weeks.
