The Texas Department of State Health Services reported a total of 1,868 cases of West Nile Virus (WNV) infecting humans in Texas in 2012. This total represents both the mild and severe forms of WNV. That is 0.007 percent of the population of Texas. Counties across Texas, including Dallas, have responded to WNV by spraying their entire populations with the pesticide called Duet.
Duet’s active ingredients are Sumithrin and Prallethrin. Hazards identification of Sumithrin on the MSDS sheet list the following under Potential Health Effects,
"The toxicological properties of this material have not been investigated. Use appropriate procedures to prevent opportunities for direct contact with the skin or eyes and to prevent inhalation."
Hazards identification of Prallethrin on the MSDS sheet list the following,
"According to Directive 67/548/EEC and all subsequent amendments, the substance prallethrin is classified as follows: T, Toxic; R23 – Xn, Harmful;R22 – N, Dangerous for the environment; R50/53. The substance may cause some toxic effects to man and hazards to various aquatic species."
The hazards of the pesticides are not well known but officials ordering the spraying have been warned. Jim Schultz of The Dallas Observer found where Dr. David Bellinger of the Harvard School of Public Health and Boston Children’s Hospital warned Dallas officials about the effects of these pesticides on young children.
"Bellinger said pesticides can have stealth effects on brain development in young children that may not show up for decades. He said these effects do not necessarily bring a child to medical attention, but can nevertheless limit their futures by causing intellectual deficits and abnormal behavior."
Instead of using sprays, Fort Worth, Texas has elected to educate its citizens in the control of mosquitoes. Forth Worth provides this information on their website
- Avoid going outdoors at dawn and dusk when mosquitoes are most active
- Use insect repellent with DEET, picaridin or oil of lemon eucalyptus on exposed skin.
- Wear long sleeves and pants to leave less of your skin exposed. Spraying clothing with permethrin provides extra protection.
- Remove mosquito habitats from your property. Drain standing water where mosquitoes can breed, and maintain your swimming pool. Any amount of standing water can give mosquitoes a place to lay their eggs. The city is calling on residents to help control mosquito population by working with your neighbors to find standing water.
The answer some counties have for saving 0.007 percent of the population from West Nile Virus is to expose 100 percent of the population to pesticides known to be toxic to humans and the environment. The benefits of the pesticides are under review by the Centers for Disease Control and Prevention (CDC).
The CDC has yet to come to a consensus on how effective the sprays are at controlling the WNV. The risks associated with spraying may not be realized for another decade or two and all for to an overblown panicked response to what is considered to be a fairly mild disease.