Safe mosquito control, for Zika & beyond | Pesticide Action Network
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Safe mosquito control, for Zika & beyond

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Zika mosquito

PAN stands in solidarity with families that have been impacted by microcephaly and other serious health impacts of the Zika virus. Unfortunately, the primary response to the outbreaks to date has been widespread spraying with pesticides to control mosquito populations. Decades of vector management around the world show that this approach is not only often ineffective, it can also compound the risks to human health.

Zika is a mosquito-borne disease, spread by the daytime biting Aedes aegypti or Aedes albopictus mosquitoes, and outbreaks are occurring throughout Latin and Central America — as well as parts of North America. According to the Centers for Disease Control and Prevention (CDC),  more than 2,250 cases had been documented in the U.S. as of August 18, with the states of Florida, New York and California among the most affected. In addition, more than 7,850 cases have been reported in the U.S territory of Puerto Rico. 

Urgent action to control the spread of this dangerous virus is clearly needed. Individuals can reduce their risk of exposure with the commonsense steps outlined below, and PAN International urges officials at all levels of government to pursue the safest, most effective approaches to controlling mosquito populations.

Integrated Vector Management works

Experiences from around the world in dealing with mosquito-borne diseases like malaria, dengue and chikunguya have shown the hazards of relying on pesticide spraying as the primary tool to combat vector-borne (e.g. mosquito) diseases.

Mosquitoes rapidly develop resistance to pesticides, leaving the chemicals wholely ineffective. Successive generations of pesticides — from extremely hazardous ones like DDT to the present day use of pyrethroids — have demonstrated this trend. The World Health Organization underscored the problem in their 2012 guidance on policy-making for Integrated Vector Management (IVM):

Resistance to insecticides is an increasing problem in vector control because of the reliance on chemical control and expanding operations . . . Furthermore, the chemical insecticides used can have adverse effects on health and the environment.” 

Many of the pesticides used in an attempt to control mosquitoes can be harmful to human health, in both the short and long term. Naled, for example, one of the organophosphate (OP) insecticides being used in response to the Zika outbreaks, is linked to a range of short term impacts including convulsions, dizziness, vomiting and unconsciousness. Long term impacts of Naled exposure can be serious — particularly for children — as it is a hormone disruptor and a reproductive and developmental toxicant.

Many studies have also linked prenatal exposure to OP pesticides to neurological harms, including increased risk of autism and reduced IQ levels.

In case after case, vector control relying on a community-based, least toxic version of IVM (see table below) has proven to be much more effective in controlling mosquito populations and, therefore, the diseases they transmit. As PAN Senior Scientist Dr. Marcia Ishii-Eiteman notes:

Investing in least-toxic IVM is a win-win for communities. It's the best way to both control mosquitoes and avoid reliance on health-harming pesticides."

Commonsense steps for prevention

Individuals and communities can take effective steps to reduce mosquito populations in and around homes, and to reduce the possibility of getting bitten by mosquitoes. The Centers for Disease Control, the Hesperian Foundation and the Natural Resources Defense Council all provide tips for families and communities to prevent infection with the virus. A few key steps include:

  • Preventing mosquito breeding sites by regularly removing sources of stagnant water from bird baths, swimming pools, planters, etc.;
  • Preventing mosquito bites by wearing long sleeved clothing and applying repellents with safe biological and botanical ingredients including neem, lemon and eucalyptus;
  • Preventing mosquitoes from entering homes by repairing window screens and ensuring there are no unscreened openings through which mosquitoes can enter; and
  • Managing water bodies, like backyard or park ponds, that are potential larval habitats for mosquitoes through habitat modification, biological control (e.g., larva killing fish) or larviciding (preferably with biological larvicides).

With the concerted efforts of individuals, communities and vector control agencies, Zika and other vector borne diseases can be controlled safely and effectively — without harming human health or the environment.

See the table below to assess the relative risks of various mosquito control methods. For more in-depth information on IVM, please refer to PAN International's decision-making framework for malaria control.

Zika vector control

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DrJan Garrett's picture
DrJan Garrett /
<p>Being on the mailing lists of many politicians, mostly Democrats, running for office, I have received quite a few letters calling out their rivals for inaction on Zika. &nbsp;Action is indeed needed, but of course ecologically stupid action is not. My impression is that the main concern is making money available to fund action, which is important, but if it means funding mass spraying of a generic pesticide, the results can easily be problematic if not catastrophic for people and other life forms (though it would boost the profits of the pesticide industry). &nbsp;Given what I know about PAN, your group might be well positioned to guide wise action by Congress and/or the relevant parts of the executive branch, perhaps making it possible to avoid excessive haste in the name of "doing something."</p> <p>I would like to know what concrete steps involving collaboration with government officials and political representatives you are involved in. If I am able to help, I would be glad to consider doing so.</p>
Pesticide Action Network's picture
Pesticide Actio... /
<p><span style="color:rgb(56,118,29)"><i>Thanks for your response. It is absolutely critical to influence how the funding on vector control for <span>zika</span> and other vector borne diseases is allocated. PAN is not directly involved in this effort but very supportive of&nbsp; our DC-based partners who may be better positioned working on this issue, such as Beyond Pesticides. Please see this links for more on their work:<br /> <br /> <a data-saferedirecturl=";q=;source=gmail&amp;ust=1473802663265000&amp;usg=AFQjCNGL6d1COkJUD_sgH66z8zrDGAjCfA" href="" target="_blank">http://www.<span>beyondpesticides</span>.or<wbr />g/programs/mosquitos-and-insec<wbr />t-borne-diseases/overview</a><br /> <br /> Thanks for your support!</i></i></i></i></span></p>
Cheryl Johnson's picture
Cheryl Johnson /
<p>All these new jobs. Follow the money. Now we have the exciting panic which is fueling all the jobs which vector control is providing. No doubt the panic is causing that to be one of the best jobs in the country. "Save me and my babies, vector control!"-from the evil Zika virus...</p> <p>My neighbor, a known public nuisance, was attempting to cause trouble in the neighborhood by constantly complaining to vector control. The results have been, for example, his bushes were sprayed with their standard toxic mix, which DOES NOT kill mosquitos, being sprayed on his bushes, notably on a particular type of bush which seems narcotic in it's huge attracting of bees for the last 50 years. The next days following, I found dead honeybees on my driveway every day for weeks. Also, VC sprayed a trickle of water in the gutter which accumulates from my neighbors' sprinklers in the mornings. Before the blazing CA sun evaporates it, I have seen a number of birds gratefully drinking from it, including hummingbirds and a mated pair of hawks. Shades of DDT... I wonder how the eggs of birds are affected by consumption of poisoned water and insects.</p> <p>Everyone saw this week's news about the millions of kept honeybees "accidently" sprayed by VC. They should pay for the destruction they are causing in their random, bumbling poisoning of our neighborhoods and enviornment, and there should be more thought and oversight given to this poisoning.</p> <p>Cheryl Johnson</p>
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