Tarrant County Public Health Director Vinny Taneja is recommending aerial spraying to combat the growing the threat from the West Nile virus across North Texas.
During Tuesday’s Commissioner’s Court meeting, Taneja said the number of infected culex mosquitoes continues to climb and the eight human cases of West Nile are essentially double of what was seen at the same time last year.
“We need to consider aerial spraying,” Taneja told commissioners.
The court took no action but Tarrant County Administrator G.K Maenius told commissioners they will contact the county’s 41 municipalities to see if there is a consensus for aerial spraying.
Some cities, including Fort Worth and Mansfield, said they were waiting to hear from the county before making any decision on aerial spraying.
“Tarrant County is our public health provider and they have not advised us on a plan,” said Brandon Bennett, Fort Worth’s code compliance director by email. “They need to make a recommendation to the city for us to consider.”
In Mansfield, city spokeswoman Belinda Willis echoed a similar theme: “When we hear from Tarrant County, we're happy to participate in the dicsussion.”
In Colleyville, City Council members discussed the possibility of aerial spraying at its August 10 work session and expressed a preference for continuing with its mosquito management plan “that focuses on targeted, localized spraying with all-terrain vehicles and backpack units,” said Colleyville spokesman Dustin Dangli.
The mosquito plan also mentions aerial spraying “in conjunction with the regional approach administered by the Tarrant County Public Health Department,” Dangli said. “The council did add if there is a county health emergency they would be open to exploring the issue further.”
So far this year, Tarrant County Public Health has tested 3,135 mosquito samples and 319 have come back positive, including 54 in Fort Worth, 46 in Arlington, 20 in Euless and 18 in Grapevine.
In 2012, when North Texas experienced a West Nile outbreak, some cities opposed aerial spraying over health concerns for their pets and insects such as bees.
But Taneja said ground spraying appears to have have reached its limit and other options are needed.
$1 million Cost to spray the entire county by air.
To spray countywide would cost about $1 million each time. To be most effective, the county would need to spray three times.
As an alternative, Taneja said the county could do targeted spraying in a one-mile radius around traps that have tested positive, which would cost $350,000-$400,000 each time.
$350,000 Cost to do targeted spraying across Tarrant County
But Taneja said “you get what you pay for” with the spraying and that covering the entire county would be most effective.
Taneja also urged homeowners to spray their own backyards to reduce the population around their home.
Maenius also told commissioner they will search for funds for the spraying since there isn’t a line item in the county budget for undertaking this type of effort.
Tarrant County Judge Glen Whitley also asked the district attorney’s office to research what legal authority the county would have to order a countywide aerial spraying.
Taneja said the county has historically worked on “a consensus basis” with cities.
While West Nile is carried by the culex mosquito, which bites at night, the Zika virus, which has captured worldwide attention, is carried by the aedes mosquito that bites during the daytime.
Aerial spraying at night for West Nile would not impact the aedes mosquito population. To impact aedes mosquitoes would require spraying during the day.
Texas led the nation with 1,868 West Nile cases in 2012, including 89 deaths. The epidemic was worst in Dallas County, which recorded 398 cases and 20 deaths, and Tarrant County, which had 280 cases and 11 deaths.
We need to consider aerial spraying.
Tarrant County Public Health Director Vinny Taneja
Last year, Tarrant recorded 30 human cases and one death. Across Texas, there were 275 confirmed human cases of West Nile and 16 deaths.
Taneja said there is no guarantee North Texas is headed to another year like 2012 but he said the numbers are concerning.
“Are we going to see an explosive outbreak?” Taneja said. “We don’t know but do we have a high number infected mosquitoes. We’re trying to prevent another outbreak. We want to reduce the number of human cases.”
Dallas could spray for Zika instead of West Nile
In July, Dallas County commissioners gave its Health and Human Services officials the authority to spray for West Nile. Dallas County currently has had 19 human West Nile cases, including one death.
But Zachary Thompson, director of Dallas County’s Health and Human Services, said they are more focused now on spraying for Zika if Dallas County has a locally transmitted case. Dallas County has reported 27 travel-related cases on Zika.
“One of the lessons learned from Florida is that fogging door-to-door didn’t work,” Thompson said. “The mosquitoes appeared to be resistant to the pesticide so we would be looking to be go to aerial sooner for Zika. We would be looking at it if we had two or more locally transmitted cases.”
On Monday, the Texas Department of State Health Services reported the state’s first travel-related Zika case from Florida.
Texas has reported 109 cases travel-related Zika cases across the state, including three pregnant women, two infants infected before birth, and one person who had sexual contact with a traveler
Dallas County hasn’t completely ruled out spraying for West Nile but Thompson said the season may be close to peaking. He also said the community support isn’t there for West Nile aerial spraying.
“We may be approaching our peak on West Nile,” Thompson said. “We'll definitely know in the next two weeks. Historically, this is the time of year where we start seeing our numbers go down but there could still be a late surge.”
This report contains information from the Star-Telegram archives.