Science Research Related to WNV and Treatment


The references below refer to other pesticide ingredients used in Ultra-Low-Volume (ULV) treatment. Regardless of the active ingredient, ULV technology allows extremely low amounts of pesticide to be effective against mosquitoes and safe when used according to label directions.

  • Efficacy of Aerial Spraying of Mosquito Adulticide in Reducing Incidence of West Nile Virus, California, 2005

    Results indicated that the odds of WNV infection after spraying were approximately six times higher in the untreated area than in treated areas, and that the treatments successfully disrupted the WNV transmission cycle. Our results provide direct evidence that aerial mosquito adulticiding is effective in reducing human illness and potential death from WNV infection.

  • Pesticide Spraying for West Nile Virus Control and Emergency Department Asthma Visits in New York City, 2000

    The number of asthma visits was similar in the 3-day periods before and after treatment operations. Daily rates of asthma visits were not associated with treatment. Secondary analyses among children and for chronic obstructive pulmonary disease yielded similar results. This analysis showed that treatment with pyrethroids for WNV control in New York City was not followed by increases in public hospital Emergency Department visit rates for asthma.

  • Community Aerial Mosquito Control and Naled Exposure

    Florida Department of Health (FLDOH) and the Centers for Disease Control and Prevention (CDC) assessed human exposure to ultra-low volume (ULV) aerial pesticide applications. These data suggest that aerial spraying does not result in increased levels of pesticide in humans, provided the pesticide is used according to label instructions.

  • The effect of pesticide spraying on the rate and severity of ED asthma.

    A report on the incidence of emergency department asthma presentations and admissions to the Lincoln Hospital, located in the South Bronx of New York City, during the 1999 eradication program of the mosquito vector for West Nile virus. Treatment with Malathion and Resmethrin occurred in the hospital's geographic area over a period of four days. The treatment did not increase the rate or severity of asthma presentations as measured by the hospital's Emergency Department asthma census or hospital admissions for asthma.

  • Evaluation of efficacy and human health risk of aerial ultra-low volume applications of pyrethrins and piperonyl butoxide for adult mosquito management in response to West Nile virus activity in Sacramento County, California.

    The Sacramento and Yolo Mosquito and Vector Control District conducted aerial applications of Evergreen pyrethrins + piperonyl butoxide for a period of three nights over approximately 83 square miles in Sacramento County. Results showed a significant decrease in mosquito numbers and WNV infection rates. Human-health risks from exposure to the insecticide were below thresholds set by the U.S. Environmental Protection Agency.

  • A human-health risk assessment for West Nile virus and insecticides used in mosquito management.

    Worst-case risk assessment was used to evaluate human-health risks for WNV and the insecticides most commonly used to control adult mosquitoes. Potential 1-day and 90-day residential exposures from each insecticide were determined. Results from this risk assessment and the current weight of scientific evidence indicated that human-health risks from residential exposure to mosquito insecticides are low and are not likely to exceed levels of concern. Based on human-health criteria, the health risks from WNV exceed the risks from exposure to mosquito insecticides.

  • Bystander Exposure to Ultra-Low-Volume Insecticide Applications Used for Adult Mosquito Management

    The objective of the current study was to estimate skin exposures to the insecticide active ingredient permethrin (another synthetic pyrethroid) using water- (Aqua-Reslin®) and oil-based (Permanone® 30-30) formulations. The estimated average absorbed skin exposure was 0.00005 to 0.00009 mg/kg body weight. The estimated exposures support the findings of previous risk assessments that exposure to ULV applications used for mosquito management are below regulatory levels of concern.

  • Risk Assessments for Exposure of Deployed Military Personnel to Insecticides and Personal Protective Measures used for Disease-Vector Management

    The researchers used risk assessment methodologies to evaluate health risks of insecticides to deployed U.S. military personnel. The focus was on toxicity and cancer risk for short, medium and long-term exposures after insecticide application and use of personal protective measures (insecticide-treated clothing) in different scenarios. Results showed that health risks from exposures to insecticides and personal protective measures used by military personnel are low.

  • Nontarget effects of aerial mosquito adulticiding with water-based unsynergized pyrethroids

    No significant nontarget mortalities were observed in honey bees; mealybug destroyers and green lacewings. No bees exhibited signs of sublethal exposure to insecticides. Beehives exposed to the insecticidal applications remained healthy and productive, and performed as well as the control hives.

  • Mortality of Nontarget Arthropods from An Aerial Application of Pyrethrins

    Mortality of nontarget insects and arthropods from ULV aerial application of pyrethrins was monitored. The observed mortality was approximately 10-fold greater in the treated area than in the control area. Midges and ants made up 61% of the arthropods collected from the treatment area; No insects larger than 1/3 of an inch were knocked down by the treatment. This study supports previous work that the impact of a single ULV application of pyrethrins was limited to a variety of small-bodied insects.

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