“Mosquito borne diseases are among the world’s leading causes of illness and death today. The World Health Organization estimates that more than 300 million clinical cases each year are attributable to mosquito borne illnesses. Despite great strides over the last 50 years, mosquito borne illnesses continue to pose significant risks to parts of the population in the United States.” Those words are not hyperbole from a pesticide manufacturer, but are the opening words of the joint statement on mosquito control from the U.S. Environmental Protection Agency and the Centers for Disease Control and Prevention.

Zika virus, that is spread to people primarily through the bite of an infected Aedes species mosquito, has become a matter of real concern.

Local mosquito borne transmission of Zika virus has recently been reported in Puerto Rico, the U.S. Virgin Islands, and America Samoa. No local mosquito borne Zika virus disease cases have yet been reported in continental U.S., but there have been travel associated cases.

In response to my recent blog post, LEED Buildings and the Zika Virus, I received numerous inquiries about pesticides and determined to post this general explanation about pesticides. Pesticides for mosquito control in the curtilage of buildings generally fall into three categories:

Controlling mosquitoes at the larval stage, in water on the property before they can mature into adult mosquitoes and disperse is considered by many professionals to be ideal. Liquid larvicide products are applied directly to water (e.g., storm water management ponds, landscaping features, etc.) using backpack sprayers and truck mounted sprayers. Tablet, pellet, granular, and briquet formulations of larvicides can also be applied. While there are a number of active ingredients used in larvicides, among the most popular is methoprene.

Controlling adult mosquitoes is most common in the U.S. Adulticides are commonly the organophosphate insecticides malathion and naled and the synthetic pyrethroid insecticides prallethrin, etofenprox, pyrethrins, and permethrin (although, despite that permethrin has been among the most widely used in the Americas it appears of dubious efficacy in killing Aedes mosquitoes today). Mosquito adulticides are applied as ultra low volume (i.e., the sprayers dispense very fine aerosol droplets that stay aloft and kill flying mosquitoes on contact), typically less than 3 ounces per acre, which minimizes exposure and risks to people and the environment.

Typical of government in this arena, EPA action has had the practical effect of banning the effective and inexpensive insecticide temephos, when the agency required new safety testing that would have cost Millions of dollars forcing the manufacturers to stop producing it. But for immediate use, there are large stockpiles.

Misting systems are becoming increasingly popular. Popular in recent years for residential use, timed release outdoor misting systems well control mosquitoes at specific locales. The insecticides most often used in outdoor misting systems contain the same pyrethrins and permethrin.

EPA, as well as the CDC and many mosquito control professionals, believe that a combination of approaches is most effective at combating mosquito populations in the built environment. For example, mosquitoes breed in water, so the elimination of standing water around buildings is an essential part of any approach to controlling mosquitoes. Because mosquitoes may travel miles as adults, any management efforts, including still theoretical genetic modification of male mosquitoes, may provide only temporary control.

Make no mistake, mosquitos kill more people than any other animal, annually, and in the history of humans.

And such does take into account Zika virus babies born with malformed brains or adults suffering the progressive paralysis of Guillain Barre syndrome.

Even E.O. Wilson, the well known evolutionary biologist and a champion of biodiversity, argues that the Aedes mosquito should be targeted, its DNA preserved and the species wiped out.

With Zika virus sweeping through South and Central America and the warm weather of Spring coming to North America, the outbreak requires an immediate response by building owners with pesticides.

Across the continental U.S. and certainly now in locales like the counties in Florida that are subject to Governor Rick Scott’s Executive Order 16-29, and expressly including LEED buildings with insect management plans, building owners should  make certain those plans are appropriate and correctly implemented given what we know about Zika and other mosquito borne illnesses, including applying pesticides to kill mosquitoes.

There are federal, state and local laws that vary across the country about pesticides, but government has failed to protect people from mosquitoes. EPA’s required labeling admonition is prudent, “Pesticide labels provide instructions about proper handling, use, and application rates of the product, and precautions to protect people and the environment.” Read the label. And then, do the right thing (.. yes, there is much more than only mitigating risk for landlords), apply pesticides to wipe out Zika virus carrying mosquitoes.