Surveillance program detects mosquitoes carrying West Nile virus

Published: 05/13/2022, 3:59 PM

(TULSA, Okla.) Tulsa Health Department (THD) officials confirmed that a sample of mosquitoes from a trap in Tulsa County has tested positive for West Nile virus (WNV). It is important for residents to remember to take precautions against WNV and other mosquito-borne illnesses. At this time, there have been no confirmed cases of WNV in humans in Tulsa County this year. 

Mosquitoes can transmit diseases like West Nile virus, so public health officials strongly encourage the use of insect repellent containing DEET to protect yourself. 

THD operates a nationally recognized mosquito surveillance program in order to confirm when mosquito-borne illnesses is present in the community. Mosquito traps are set weekly in various locations throughout Tulsa County. Samples are collected and tested weekly for the presence of mosquito-borne illnesses. The Tulsa Health Department operates on an efficient budget to control mosquito populations during the spring and summer by surveillance and treats instead of spray. 

The objective of the surveillance is to detect the presence of mosquitoes, determine abundance, species, make a risk assessment, and provide a basis for control. Control methods include larviciding and spraying when necessary. Public health is the primary driver for preventing disease infection in Tulsa County. 

The months of July through October are typically the highest risk months for exposure to WNV in Oklahoma, however THD proactively begins a mosquito surveillance program each May.   

“We start setting traps as part of our surveillance program in early May to monitor for West Nile virus, and to identify any positive mosquitoes as early as possible,” said Michael Morrison, vector control coordinator. “Our mosquito control program recognizes the importance of preventing mosquito-borne illness by educating the public on bite prevention and identifying and dumping any standing water. THD is prepared to act in the affected areas as soon as weather conditions allow.”  

West Nile virus is spread through the bite of an infected mosquito, which feeds on infected birds and then transmits the virus when biting humans, horses, and some other mammals. Symptoms of WNV include sudden onset of fever, headache, dizziness and muscle weakness. 

“There have been positive mosquito tests in previous years as well as human cases of West Nile virus disease in Tulsa County, unfortunately, some of those people have died of the illness,” said Morrison. “It is important to take steps to prevent mosquitos from biting you and your family. Prevention is easy with these steps.” 

 Precautions to take against mosquito bites are the following: 

  • Dump and drain items such as buckets, cans, pool covers, flower pots, and tires from holding standing water so mosquitoes don’t have a place to breed. 
  • Use an insect repellent containing DEET or other CDC approved repellents on exposed skin and clothing when you go outdoors, particularly if you are outside between dusk and dawn when mosquitoes are more likely to bite. (Insect repellent with permethrin should be used on clothing only.) 
  • Wearing long sleeves and long pants that are loose-fitting and made of light colors. 
  • Repair or install window and door screens to keep mosquitoes out of your home. 
  • Encourage your friends and neighbors to dump and drain and to use repellents. 
  • Clean leaves and debris from rain gutters regularly to ensure they are not clogged. 

To place a complaint about mosquitoes in your area or to report standing or stagnant water in your area, please call 918-582-9355 or submit an online environmental complaint form on the Tulsa Health Department website at Making a report does not guarantee immediate action but provides the vector control team data to determine locations for traps. Trapping and testing will continue until the numbers of mosquitoes subside in the fall months.  

"It is very important that community members do their part to dump standing water, to prevent mosquitoes from having breeding sites available to them. Standing water can occur in several places such as bird baths, toys, kiddie pools, trash cans, buckets, inverted grill lids, planters, bowls, etc,” said Morrison. “Our department is here as a resource if you would like help inspecting your property for possible mosquito breeding locations.” 

Click here for our interactive data page that includes a map of WNV positive trap locations in Tulsa County. This is updated weekly. Click here for visuals including traps, spraying trucks, testing mechanisms, larvicide and adulticide (this link expires in 7 days).   

The 2022 mosquito season by the numbers: 

1 trap sample tested positive for West Nile Virus  

43 trap samples have been tested so far this season 

811* mosquitoes collected for testing *approximately 

0 human cases of WNV in Tulsa County 

0 human case of WNV in Oklahoma 


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