The Lake County General Health District (LCGHD) conducts mosquito treatment in most of the municipalities in Lake County that are densely populated. Treatment reduces the risk of mosquito-borne diseases and provides for a more comfortable summer environment. Since mosquitoes may be infected with both La Crosse and St. Louis Encephalitis Virus, and human cases with this disease have been identified in the Health District in the past, mosquitoes can be considered a public health nuisance. The public health significance of mosquitoes has been amplified by the recent spread of the West Nile Virus. The Health District is licensed through the Ohio Department of Agriculture to apply pesticides for the purpose of mosquito control. If you have any further questions that are not answered from this web site, please contact our offices on weekdays between 8:00 a.m. and 4:30 p.m. at (440) 350-2543 or (440) 918-2543.

Spraying has concluded for the 2024 season. Please continue to check our website or call the Mosquito Hotline for updates.

The Mosquito Control Program Treatment Schedule

Cancellation for Mosquito Treatment

The treatment schedule can change daily. Any of the following conditions can delay or cancel treatment:

  • Number of adult mosquitoes trapped at specific trap site location below the threshold value for treatment
  • Winds greater than 15 mph
  • 50% or greater chance of rain
  • Temperatures cooler than 55 degrees
  • Mechanical failures
  • We will evaluate if spray is warranted on an Air Quality Advisory day

Areas to be treated are determined by the number of mosquitoes trapped at our trap sites, complaints, and past history.















Some parts of Lake County are experiencing an increase in mosquito activity during certain times of day, especially areas near bodies of stagnant water. If you’re planning to be outside this Labor Day weekend, be sure to use insect repellents that have DEET, Picaridin (KBR 3023), Oil of Lemon Eucalyptus (PMD), or IR3535. We will continue spraying according to our mosquito spraying schedule. We post our schedule above and also to our Facebook and X pages.

Pesticides Used by LCGHD

PesticideSafety Data SheetPurpose
Duet LabelDuet Label SDSAdult Mosquito/Night Treatment
Natular G30 LabelNatular G30 SDSLarval Mosquito/Standing Water
Natular T30 LabelNatular T30 SDSLarval Mosquito/Standing Water
Natular XRT LabelNatular XRT SDSLarval Mosquito/Standing Water
Merus 3.0 LabelMerus 3.0 SDSAdult Mosquito/Night Treatment
Natular DT LabelNatular DT SDSLarval Mosquito/Standing Water

Helpful Pesticide Links

Vector-Borne Diseases

Midges and Mayflies

Mosquito Tips for Homeowners